question,answer
What is the definition of Alanine Metabolism?,"Alanine (L-Alanine) is an α-amino acid that is used for protein biosynthesis. Alanine transaminase can facilitate the reductive amination of pyruvate to produce alanine. L-Alanine can be converted to pyruvic acid by alanine aminotransferase 1 reversibly coupled with interconversion of oxoglutaric acid and L-glutamic acid. L-Alanine can also be produced by alanine-glyoxylate transaminase with coupled interconversion of glyoxylate and glycine. L-Alanine will be coupled with alanyl tRNA by alanyl-tRNA synthetase to perform protein biosynthesis. Alanine constitutes about 8% of human proteins. Under fasting conditions, alanine, derived from protein breakdown, can be converted to pyruvate and used to synthesize glucose via gluconeogenesis in the liver. Alternately, alanine, after conversion to pyruvate, can be fully oxidized via the TCA cycle in other tissues."
What is the definition of Aspartate Metabolism?,"Aspartate is synthesized by transamination of oxaloacetate by aspartate aminotransferase or amino acid oxidase. Aspartyl-tRNA synthetase can then couple aspartate to aspartyl tRNA for protein synthesis. The aspartate content in human proteins is about 7%. Asparagine synthase can convert aspartate to the polar amino acid asparagine. Aspartate is also a precursor for cellular signaling compounds such as, N-acetyl-aspartate, beta-alanine, adenylsuccinate, arginino-succinate and N-carbamoylaspartate. Aspartate is also a metabolite in the urea cycle and involved in gluconeogenesis. Additionally, aspartate carries the reducing equivalents in the mitochondrial malate-aspartate shuttle, which utilizes the ready interconversion of aspartate and oxaloacetate. The conjugate base of L-aspartic acid, aspartate, also acts as an excitatory neurotransmitter in the brain which activates NMDA receptors."
What is the definition of Glutamate Metabolism?,"Glutamate is one of the non-essential amino acids that is produced by the body. Glutamate is precursor for many nucleic acids and proteins in addition to its role in the central nervous system. It is an excitatory neurotransmitter and has a role in neuronal plasticity, affecting memory and learning.  Glutamate plays a role in numerous metabolic pathways. Dysfunctional glutamate metabolism may cause disorders such as: gyrate atrophy, hyperammonemia, γ-hydoxybutyric aciduria, hemolytic anemia, and 5-oxoprolinuria. "
What is the definition of Glutathione Metabolism?,"Glutathione (GSH) is an low-molecular-weight thiol and antioxidant in various species such as plants, mammals and microbes. Glutathione plays important roles in nutrient metabolism, gene expression, etc. and sufficient protein nutrition is important for maintenance of GSH homeostasis. Glutathione is synthesized from glutamate, cysteine, and glycine sequentially by gamma-glutamylcysteine synthetase and GSH synthetase. L-Glutamic acid and cysteine are synthesized to form gamma-glutamylcysteine by glutamate-cysteine ligase that is powered by ATP. Gamma-glutamylcysteine and glycine can be synthesized to form glutathione by enzyme glutathione synthetase that is powered by ATP, too. Glutathione exists oxidized (GSSG) states and in reduced (GSH) state. Oxidation of glutathione happens due to relatively high concentration of glutathione within cells."
What is the definition of Citric Acid Cycle?,"The citric acid cycle, which is also known as the tricarboxylic acid cycle (TCA cycle) or the Krebs cycle, is a connected series of enzyme-catalyzed chemical reactions of central importance to all aerobic organisms (i.e. organisms that use oxygen for cellular respiration). The citric acid cycle is named after citrate or citric acid, a tricarboxylic acid that is both consumed and regenerated through this pathway. The citric acid cycle was discovered in 1937 by Hans Adolf Krebs while he worked at the University of Sheffield in England (PMID: 16746382). Krebs received the Nobel Prize for his discovery in 1953. Krebs’ extensive work on this pathway is also why the citric acid or TCA cycle is often referred to as the Krebs cycle. Metabolically, the citric acid cycle allows the release of energy (ultimately in the form of ATP) from carbohydrates, fats, and proteins through the oxidation of acetyl-CoA. The citric acid cycle also produces CO2, the precursors for several amino acids (aspartate, asparagine, glutamine, proline) and NADH – all of which are used in other important metabolic pathways, such as amino acid synthesis and oxidative phosphorylation (OxPhos). The net yield of one “turn” of the TCA cycle in terms of energy-containing compounds is one GTP, one FADH2, and three NADH molecules.  The NADH molecules are used in oxidative phosphorylation to generate ATP. In eukaryotes, the citric acid cycle occurs in the mitochondrial matrix. In prokaryotes, the citric acid cycle occurs in the cytoplasm.  In eukaryotes, the citric acid or TCA cycle has a total of 10 steps that are mediated by 8 different enzymes.  Key to the whole cycle is the availability of acetyl-CoA. One of the primary sources of acetyl-CoA is from the breakdown of glucose (and other sugars) by glycolysis. This process generates pyruvate. Pyruvate is decarboxylated by pyruvate dehydrogenase to generate acetyl-CoA. The citric acid cycle begins with acetyl-CoA transferring its two-carbon acetyl group to the four-carbon acceptor compound (oxaloacetate) to form a six-carbon compound (citrate) through the enzyme citrate synthase. The resulting citrate is then converted to cis-aconitate and then isocitrate via the enzyme aconitase.  The resulting isocitrate then combines with NAD+ to form oxalosuccinate and NADH, which is then converted into alpha-ketoglutarate (and CO2) through the action of the enzyme known as isocitrate dehydrogenase. The resulting alpha-ketoglutarate combines with NAD+ and CoA-SH to produce succinyl-CoA, NADH, and CO2. This step is mediated by the enzyme alpha-ketoglutarate dehydrogenase. The resulting succinyl-CoA combines with GDP and organic phosphate to produce succinate, CoA-SH, and GTP. This phosphorylation reaction is performed by succinyl-CoA synthase. The resulting succinate then combines with ubiquinone to produce two compounds, fumarate and ubiquinol through the action of the enzyme succinate dehydrogenase.  The resulting fumarate is then hydrated by the enzyme known as fumarase to produce malate. The resulting malate is oxidized via NAD+ to produce oxaloacetate and NADH. This oxidation reaction is performed by malate dehydrogenase.  The resulting oxaloacetate can then combine with acetyl-CoA and the TCA reaction cycle begins again. Overall, in the citric acid cycle, the starting six-carbon citrate molecule loses two carboxyl groups as CO2, leading to the production of a four-carbon oxaloacetate. The two-carbon acetyl-CoA that is the “fuel” for the TCA cycle can be generated by several metabolic pathways including glucose metabolism, fatty acid oxidation, and the metabolism of amino acids.  The overall reaction for the citric acid cycle is as follows: acetyl-CoA + 3 NAD+ + FAD + GDP + P + 2H2O = CoA-SH + 3NADH + FADH2 + 3H+ + GTP + 2CO2. Many molecules in the citric acid cycle serve as key precursors for other molecules needed by cells.  The citrate generated via the citric acid cycle can serve as an intermediate for fatty acid synthesis; alpha-ketoglutarate can serve as a precursor for glutamate, proline, and arginine; oxaloacetate can serve as a precursor for aspartate and asparagine; succinyl-CoA can serve as a precursor for porphyrins; and acetyl-CoA can serve as a precursor fatty acids, cholesterol, vitamin D, and various steroid hormones. There are several variations to the citric acid cycle that are known. Interestingly, most of the variation lies with the step involving succinyl-CoA production or conversion.  Humans and other animals have two different types of succinyl-CoA synthetases. One produces GTP from GDP, while the other produces ATP from ADP (PMID: 9765291). On the other hand, plants have a succinyl-CoA synthetase that produces ATP (ADP-forming succinyl-CoA synthetase) (Jones RC, Buchanan BB, Gruissem W. (2000). Biochemistry & molecular biology of plants (1st ed.). Rockville, Md: American Society of Plant Physiologists. ISBN 0-943088-39-9.). In certain acetate-producing bacteria, such as Acetobacter aceti, an enzyme known as succinyl-CoA:acetate CoA-transferase performs this conversion (PMID: 18502856) while in Helicobacter pylori succinyl-CoA:acetoacetate CoA-transferase is responsible for this reaction (PMID: 9325289). The citric acid cycle is regulated in a number of ways but the primary mechanism is by product inhibition. For instance, NADH inhibits pyruvate dehydrogenase, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, and citrate synthase. Acetyl-CoA inhibits pyruvate dehydrogenase, while succinyl-CoA inhibits alpha-ketoglutarate dehydrogenase and citrate synthase.  Additionally, ATP inhibits citrate synthase and alpha-ketoglutarate dehydrogenase. Calcium is another important regulator of the citric acid cycle. In particular, it activates pyruvate dehydrogenase phosphatase, which then activates pyruvate dehydrogenase. Calcium also activates isocitrate dehydrogenase and alpha-ketoglutarate dehydrogenase (PMID: 171557)."
What is the definition of Alpha Linolenic Acid and Linoleic Acid Metabolism?,"Linoleic acid (LNA) is a polyunsaturated fatty acid (PUFA) precursor to the longer n−6 fatty acids commonly known as omega-6 fatty acids. Omega-6 fatty acids are characterized by a carbon-carbon double bond at the sixth carbon from the methyl group. Similarly, the PUFA alpha-linoleic acid (ALA) is the precursor to n-3 fatty acids known as omega-3 fatty acids which is characterized by a carbon-carbon double bond at the third carbon from the methyl group. Both LNA and ALA are essential dietary requirements for all mammals since they cannot be synthesized natively in the body. Both undergo a series of similar conversions to reach their final fatty acid form. LNA enters the cell and is catalyzed to gamma-linolenic acid (GLA) by acyl-CoA 6-desaturase (delta-6-desaturase/fatty acid desaturase 2). GLA is then converted to dihomo-gammalinolenic acid (DGLA) by elongation of very long chain fatty acids protein 5 (ELOVL5). DGLA is then converted to arachidonic acid (AA) by acyl-CoA (8-3)-desaturase (delta-5-desaturase/fatty acid desaturase 1). Arachidonic acid is then converted to a series of short lived metabolites called eicosanoids before finally reaching it's final fatty acid form. "
What is the definition of Selenoamino Acid Metabolism?,"Selenoamino acids include selenocysteine, selenohomocysteine and selenomethionine, amino acids containing a selenium in place of a sulfur. Selenium has important biological functions but may be toxic at high doses. It is believed its toxicity arises from its induction of oxidative stress. Many selenoproteins are antioxidants. Due to its antioxidant effects selenium has become an of interest supplement to prevent diseases and cancers. Selenium and sulfur are very similar chemically, thus sulfur metabolism enzymes will act on selenium as well to form selenoamino acids which then may replace other amino acids  in protein synthesis. "
What is the definition of Amino Sugar Metabolism?,"Amino sugars are sugar molecules containing an amine group. They make up many polysaccharides including, glycosaminoglycans or mucopolysaccharides. "
What is the definition of Ammonia Recycling?,Ammonia can be rerouted from the urine and recycled into the body for use in nitrogen metabolism. Glutamate and glutamine play an important role in this process. There are many other processes that act to recycle ammonia. asparaginase recycles ammonia from asparagine. Glycine cleavage system generates ammonia from glycine. Histidine ammonia lyase forms ammonia from histidine. Serine dehydratase also produces ammonia by cleaving serine. 
What is the definition of Arginine and Proline Metabolism?,"The arginine and proline metabolism pathway illustrates the biosynthesis and metabolism of several amino acids including arginine, ornithine, proline, citrulline, and glutamate in mammals. In adult mammals, the synthesis of arginine takes place primarily through the intestinal-renal axis (PMID: 19030957). In particular, the amino acid citrulline is first synthesized from several other amino acids (glutamine, glutamate, and proline) in the mitochondria of the intestinal enterocytes (PMID: 9806879). The mitochondrial synthesis of citrulline starts with the deamination of glutamine to glutamate via mitochondrial glutaminase. The resulting mitochondrial glutamate is converted into 1-pyrroline-5-carboxylate via pyrroline-5-carboxylate synthase (P5CS). Alternately, the 1-pyrroline-5-carboxylate can be generated from mitochondrial proline via proline oxidase (PO). Ornithine aminotransferase (OAT) then converts the mitochondrial 1-pyrroline-5-carboxylate into ornithine and the enzyme ornithine carbamoyltransferase (OCT -- using carbamoyl phosphate) converts the ornithine to citrulline (PMID: 19030957). After this, the mitochondrial citrulline is released from the small intestine enterocytes and into the bloodstream where it is taken up by the kidneys for arginine production. Once the citrulline enters the kidney cells, the cytosolic enzyme argininosuccinate synthetase (ASS) will combine citrulline with aspartic acid to generate argininosuccinic acid. After this step, the enzyme argininosuccinate lyase (ASL) will remove fumarate from argininosuccinic acid to generate arginine. The resulting arginine can either stay in the cytosol where it is converted to ornithine via arginase I (resulting in the production of urea) or it can be transported into the mitochondria where it is decomposed into ornithine and urea via arginase II.  The resulting mitochondrial ornithine can then be acted on by the enzyme ornithine amino transferase (OAT), which combines alpha-ketoglutarate with ornithine to produce glutamate and 1-pyrroline-5-carboxylate.  The mitochondrial enzyme pyrroline-5-carboxylate dehydrogenase (P5CD) acts on the resulting 1-pyrroline-5-carboxylate (using NADPH as a cofactor) to generate glutamate. Alternately, the mitochondrial 1-pyrroline-5-carboxylate can be exported into the kidney cell’s cytosol where the enzyme pyrroline-5-carboxylate reductase (P5CR) can convert it to proline. While citrulline-to-arginine production primarily occurs in the kidney, citrulline is readily converted into arginine in other cell types, including adipocytes, endothelial cells, myocytes, macrophages, and neurons.  Interestingly, chickens and cats cannot produce citrulline via glutamine/glutamate due to a lack of a functional pyrroline-5-carboxylate synthase (P5CS) in their enterocytes (PMID: 19030957)."
What is the definition of beta-Alanine Metabolism?,"Beta-alanine, 3-aminopropanoic acid, is a non-essential amino acid. Beta-Alanine is formed by the proteolytic degradation of beta-alanine containing dipeptides: carnosine, anserine, balenine, and pantothenic acid (vitamin B5). These dipeptides are consumed from protein-rich foods such as chicken, beef, pork, and fish. Beta-Alanine can also be formed in the liver from the breakdown of pyrimidine nucleotides into uracil and dihydrouracil and then metabolized into beta-alanine and beta-aminoisobutyrate. Beta-Alanine can also be formed via the action of aldehyde dehydrogenase on beta-aminoproionaldehyde which is generated from various aliphatic polyamines. Under normal conditions, beta-alanine is metabolized to aspartic acid through the action of glutamate decarboxylase. It addition, it can be converted to malonate semialdehyde and thereby participate in propanoate metabolism. Beta-Alanine is not a proteogenic amino acid. This amino acid is a common athletic supplementation due to its belief to improve performance by increased muscle carnosine levels. "
What is the definition of Betaine Metabolism?,"Betaine (or trimethylglycine) is similar to choline (trimethylaminoethanol) but differs in choline's terminal carboxylic acid group trimethylglycine is reduced to a hydroxyl group. Betaine is obtained from diet as betaine or compounds containing choline in foods such as whole grains, beets and spinach. Betaine can also be synthesized from choline in the liver and kidney.  First, choline is oxidized to betaine aldehyde by mitochondrial choline oxidase (choline dehydrogenase). Then, betaine aldehyde dehydrogenase oxidizes betaine aldehyde to betaine in the mitochondria or cytoplasm. In the liver, betaine functions as a methyl donor similar to choline, folic acid, S-adenosyl methionine and vitamin B12. Methyl donors are important for liver function, cellular replication and detoxification reactions. Betaine is also involved in the production of carnitine to protect from kidney damage and functions as an osmoprotectant in the inner medulla. "
What is the definition of Biotin Metabolism?,"Biotin is a vitamin that is an essential nutrient for humans. Biotin can be absorbed from consuming various foods such as: legumes, soybeans, tomatoes, romaine lettuce, eggs, cow's milk, oats and many more. Biotin acts as a cofactor for enzymes to catalyze carboxylation reactions involved in gluconeogenesis, amino acid catabolism and fatty acid metabolism. Biotin deficiency has been associated with many human diseases. These diseases may be caused by dysfunctional biotin metabolism due to enzyme deficiencies. Some research suggests biotin may play a role in transcription regulation or protein expression which may lead to biotin related diseases. "
What is the definition of Butyrate Metabolism?,"Butyrate metabolism (Butanoate metabolism) describes the metabolic fate of a number of short chain fatty acids or short chain alcohols that are typically produced by intestinal fermentation. Many of these molecules are eventually used in the production of ketone bodies, the creation of short-chain lipids or as precursors to the citrate cycle, glycolysis or glutamate synthesis. The molecule for which this pathway is named, butyric acid, is a four-carbon fatty acid that is formed in the human colon by bacterial fermentation of carbohydrates (including dietary fiber). It is found in rancid butter, parmesan cheese, and vomit, and has an unpleasant odor and acrid taste, with a sweet aftertaste (similar to ether)."
What is the definition of Caffeine Metabolism?,"Caffeine is obtained from diet including coffee and other beverages and is absorbed in the stomach and small intestine. In the liver, the cytochrome P450 oxidase enzyme system and specifically CYP1A2 metabolizes caffeine into paraxanthine to increase lipolysis and increase free fatty acids and glycerol levels in the blood, theobromine to dilate blood vessels and increase urine volume and theophylline which relaxes bronchi smooth muscles. In the lysosome, these metabolites undergo further metabolism into methyluric acids before being excreted in the urine. There is genetic variability in the metabolism of caffeine due to the polymorphism of CYP1A2. This variability can affect the pharmacokinetic and pharmacodynamic properties of caffeine and may affect an individual's consumption. "
What is the definition of Carnitine Synthesis?,"Carnitine is an ammonium compound that exists in two stereoisomers, of which only L-carnitine is biologically active. Carnitine can be obtained from dietary sources and also biosynthesized. It is necessary for fatty acid oxidation, transporting fatty acids from the cystosol to the mitochondria, where they are broken down via the citric acid cycle to release energy. Carnitine is synthesized from lysine residues in existing proteins. These residues are methylated using lysine methyltransferase enzymes and methyl groups from S-adenosylmethionine, then removed from the protein via hydrolysis. In the next step, the N6,N6,N6-trimethyl-L-lysine is converted to 3-hydroxy-N6,N6,N6-trimethyl-L-lysine t via the mitochondrial enzyme trimethyllysine dioxygenase. The 3-hydroxy-N6,N6,N6-trimethyl-L-lysine is then cleaved to 4-trimethylammoniobutanal and glycine, likely by an aldose identical to serine hydroxymethyltransferase. Next, 4-trimethylammoniobutanal is oxidized by the 4-trimethylaminobutyraldehyde dehydrogenase protein to 4-trimethylammoniobutanoic acid. Finally, 4-trimethylammoniobutanoic acid is transformed into L-carnitine via the enzyme gamma-butyrobetaine dioxygenase. The reactions in the carnitine synthesis pathway occur ubiquitously in the human body with the exception of the last step, as the gamma-butyrobetaine dioxygenase enzyme is found only in the liver and kidney (and at very low levels in the brain). The produced carnitine is then carried to other tissue via a number of transport systems."
What is the definition of Catecholamine Biosynthesis?,"The Catecholamine Biosynthesis pathway depicts the synthesis of catecholamine neurotransmitters. Catecholamines are chemical hormones released from the adrenal glands as a response to stress that activate the sympathetic nervous system. They are composed of a catechol group and are derived from amino acids. The commonly found catecholamines are epinephrine (adrenaline), norepinephrine (noradrenaline) and dopamine. They are synthesized in catecholaminergic neurons by four enzymes, beginning with tyrosine hydroxylase (TH), which generates L-DOPA from tyrosine. The L-DOPA is then converted to dopamine via aromatic L-amino acid decarboxylase (AADC), which becomes  norepinephrine via dopamine beta-hydroxylase (DBH); and finally is converted to epinephrine via phenylethanolamine N-methyltransferase (PNMT)."
What is the definition of Cysteine Metabolism?,The semi-essential amino aid cysteine is tightly regulated in the body to ensure proper levels for metabolism but maintaining levels below toxic thresholds. Cysteine can be obtained from diet or synthesized from  O-acetyl-L-serine. Cystine is the dimeric form of cysteine. Cysteine is a precursor for protein synthesis and an antioxidant. Impaired cysteine metabolism has been linked with neurodegenerative disorders. 
What is the definition of D-Arginine and D-Ornithine Metabolism?,"D-Amino acids have been show to be present in high concentrations in humans and play a role in biological functions. D-Amino may have negative effects as they can be found in some bacteria or form spontaneously in certain reactions. D-Amino acid oxidase (DAAO) is one of the main enzymes that metabolize D-Amino acids via deamination. DAAO is highly specific towards D-amino acids and favours free neutral D-amino acids or those with hydrophobic, polar or aromatic groups. Acidic amino acids are not catalyze by DAOO. "
What is the definition of Degradation of Superoxides?,"Reactive oxygen species (ROS) are formed by the normal metabolic process of oxygen. Examples are superoxide, oxygen ions and peroxides and can be of either organic or inorganic origin. ROS are highly reactive due to unpaired valence shell electrons, and can cause serious damage to cells and cell organelles. The environment also may cause ROS to form, from sources such as drought, air pollutants, UV light, cold temperatures, and external chemicals. An organic example of ROS being formed is during the beta oxidation of fatty acids, or photorespiration in photosynthetic organisms. Aerobic organisms who produce energy through the electron transport chain in mitochondria produce ROS as a byproduct. ROS damage commmonly includes DNA damage, lipid peroxidation, oxidation of amino acids in proteins, and oxidatively inactivating enzymes by oxidation of cofactors. Most aerobic organisms have adapted to this dangerous condition of life, and have a system of enzymes and scavenging free radicals. Enzymes such as are essential for defense against ROS, and include superoxide dismutases (SODs) and hydroperoxidase (CAT). Superoxide dismutases are the primary method of disposal of ROS, and convert superoxide radicals to hydrogen peroxide and water. Catalase attacks the hydrogen peroxide produced by SODs, and converts it into oxygen and water. In skin cells, 5,6 dihydroxyindole-2-carboxylic acid oxidase in the melanosome membranes breaks down hydrogen peroxide into water and oxygen."
What is the definition of Ethanol Degradation?,"Ethanol metabolism in humans occurs mainly in the liver, though degradation has also been shown in gastric, pancreatic, and lung tissue. Ethanol degradation occurs via four pathways, three of which are oxidative pathways and are depicted here. The fourth is a nonoxidative pathway which is less well studied but known to produce fatty acid ethyl esters. Each of the three oxidative pathways is differentiated by the mechanism utilized to oxidize ethanol to acetaldehyde in the first step. In the alcohol dehydrogenase mediated ethanol degradation pathway (I), cytoplasmic alcohol dehydrogenase produces the acetaldehyde from the ethanol. In the MEOS mediated ethanol degradation pathway (II), the ethanol enters the endoplasmic reticulum, where the Microsomal Ethanol Oxidising System (MEOS), also know as also known as cytochrome P-450 2E1, does the oxidizing and returns the acetaldehyde to the cytoplasm. In the catalase mediated ethanol degradation pathway (III), the oxidation occurs in the peroxisome via peroxisomal catalase, with the resulting acetaldehyde being released to the cytoplasm. In each of the three oxidative pathways the cytosolic acetaldehyde then enters the mitochondrial compartment, where it is converted to acetate by mitochondrial aldehyde dehydrogenase. The acetate leaves the mitochondria and moves to extra-hepatic tissues for further metabolism. In extra-hepatic cells the acetate is converted to acetyl-CoA via either cytoplasmic or mitochondrial acetyl-CoA synthetase. The alcohol dehydrogenase mediated ethanol degradation pathway (I) is the predominant mechanism of catabolism under conditions of acute alcohol consumption. However, under conditions of chronic ethanol consumption the MEOS mediated ethanol degradation pathway (II) and nonoxidative pathway are induced to assist with ethanol degradation."
What is the definition of Fatty Acid Elongation in Mitochondria?,"Cells typically contain large amounts of C18 and C20 fatty acids. Longer chain fatty acids are found in certain specialized tissues (myelin contains high amounts of C22 and C24 components). Even longer chain fatty acids are derived from either dietary sources or from elongation of C16-CoA or C18-CoA formed by the cytoplasmic fatty acid synthetase system. All of the fatty acids needed by the body can be synthesized from palmitate (C16:0) except the essential, polyunsaturated fatty acids such as linoleate and linolenate. To create longer, shorter, oxidized, reduced fatty acids, palmitic acid is subjected to enzymatic reactions by reductases, hydroxylases, elongases and mixed function oxidases. There are 3 major processes that modify palmitic acid: elongation, desaturation and hydroxylation. Elongation of fatty acids may occur at endoplasmic reticulum where fatty acid molecules of length up to C24 may be produced. Mitochondrial elongation may result in fatty acids up to C16 in length. Fatty acid elongation in mitochondria is essentially the reverse of beta-oxidation for fatty acid oxidation. In particular, both pathways make use of acetyl-CoA acyltransferase, 3-hydroxyacyl-CoA dehydrogenase and enoyl-CoA hydratase. The final step of fatty acid elongation uses enoyl-CoA reductase (not part of the beta-oxidation pathway). The elongation takes place in the mitochondrial matrix. In liver and kidney fatty acid elongation operates best in the presence of both NADH and NADPH, whereas in heart and skeletal muscle, only NADH is required. The mitochondrial pathway is important for elongating fatty acids containing 14 or fewer carbon atoms. Short chain fatty acids (SCFA) are fatty acids with aliphatic tails of less than six carbons. Medium chain fatty acids (MCFA) are fatty acids with aliphatic tails of 6Š—–12 carbons. Long chain fatty acids (LCFA) are fatty acids with aliphatic tails longer than 12 carbons. Very Long chain fatty acids (VLCFA) are fatty acids with aliphatic tails longer than 22 carbons."
What is the definition of Fatty Acid Metabolism?,"Fatty acids constitute a large energy source for the body. The cellular membrane is also made up of fatty acids. During starvation times, fatty acids can provide energy to humans for numerous days. Fatty acid metabolism is also known as beta-oxidation. During metabolism, acetyl CoA is produced that can then enter the citric acid cycle. When ATP is needed, ATP may be generated by increasing fatty acid metabolism. Fatty acid metabolism is essentially the reverse reaction of fatty acid synthesis. "
What is the definition of Folate Metabolism?,"The 1-carbon transformations require folic acid (folate). Folic acid participates in both the activation of single carbons as well as in the oxidation and reduction of single carbons. Folate-dependent single-carbon reactions are important in amino acid metabolism and in biosynthetic pathways leading to DNA, RNA, membrane lipids, and neurotransmitters. To carry out the transfer of 1-carbon units, NADPH must reduce folic acid two times in the cell. The pyrazine ring of the 6-methylpterin is reduced at each of the two N-C double bonds. More precisely, the pathway leading to the formation of tetrahydrofolate (THF) begins when folate (F) is reduced to dihydrofolate (DHF) which is then reduced to THF. Dihydrofolate reductase catalyses the last step. Vitamin B3 in the form of NADPH is a necessary cofactor for both steps of the synthesis. The resulting 5,6,7,8-tetrahydrofolate (THF) is the acceptor of 1-carbon groups. Tetrahydrofolate accepts methyl groups, usually from serine. The product, N5,N10-methylene-tetrahydrofolate, is the central compound in 1-carbon metabolism. Methylene-THF (CH2FH4) is formed from THF by the addition of methylene groups from one of three carbon donors: formaldehyde, serine, or glycine. Tetrahydrofolate can also accept a methyl group from the complete breakdown of glycine. The N5,N10-methylene-tetrahydrofolate can either donate its single-carbon group directly, be oxidized by NADP to the methenyl form, or be reduced by NADH to the methyl form. Depending on the biosynthetic pathway involved, any of these species can donate the 1-carbon group to an acceptor. The methylene form donates its methyl group during the biosynthesis of thymidine nucleotides for DNA synthesis, the methenyl form donates its group as a formyl group during purine biosynthesis, and the methyl form is the donor of the methyl group to sulfur during methionine formation. Methyl tetrahydrofolate (CH3-THF) can be made from methylene-THF by reduction of the methylene group with NADPH. Another form of THF, formyl-THF or folinic acid) results from oxidation of methylene-THF or is formed from formate donating formyl group to THF. Finally, histidine can donate a single carbon to THF to form methenyl-THF."
What is the definition of Fructose and Mannose Degradation?,"Fructose and mannose are monosaccharides that can be found in many foods. Fructose can join with glucose to form sucrose. Mannose can be converted to glucose. Both may be used as food sweeteners. Fructose is well absorbed, especially in the presence of glucose. Fructose causes less of an insulin response compared to glucose and thus may be a preferred sugar for diabetics. In contrast to fructose, humans do not metabolize mannose well with the majority of it being excreted unchanged. Mannose in the urine can be beneficial in treating urinary tract infections caused be E. coli. However, mannose can be detrimental to humans by causing diabetic complications. "
What is the definition of Glycerol Phosphate Shuttle?,The glycerol phosphate shuttle also known as the glycerophosphate shuttle. It shuttles electrons to mitochondrial carriers in the oxidative phosphorylation pathway from cytosolic NADH. This shuttle relies on mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH). This is also a common process for the cell  to regenerate cytosolic NAD+ for other processes.
What is the definition of Homocysteine Degradation?,"Homocysteine is an amino acid and homologue of cysteine that appears in the body as a result of the degradation of methionine. In mammals, homocysteine is used to biosynthesize cysteine via the following pathway. First the enzyme cystathionine beta-synthetase irreversibly condenses homocysteine with L-serine, forming L-cystathionine. The L-cystathionine is then cleaved by cystathionine gamma-lyase, producing 2-oxobutanoate, L-cysteine, and ammonia. The 2-oxobutanoate is further broken down via the 2-oxobutanoate degradation pathway, producing citric acid cycle intermediates, while the L-cysteine goes to the cysteine metabolism pathway. The homocysteine degradation pathway composes a part of the larger methionine metabolism pathway."
What is the definition of Ketone Body Metabolism?,"Ketone bodies are consisted of acetone, beta-hydroxybutyrate and acetoacetate. In liver cells' mitochondria, acetyl-CoA can synthesize acetoacetate and beta-hydroxybutyrate; and spontaneous decarboxylation of acetoacetate will form acetone. Metabolism of ketone body (also known as ketogenesis) contains several reactions. Acetoacetic acid (acetoacetate) will be catalyzed to form acetoacetyl-CoA irreversibly by 3-oxoacid CoA-transferase 1 that also coupled with interconversion of succinyl-CoA and succinic acid. Acetoacetic acid can also be catalyzed by mitochondrial D-beta-hydroxybutyrate dehydrogenase to form (R)-3-Hydroxybutyric acid with NADH. Ketogenesis occurs mostly during fasting and starvation.  Stored fatty acids will be broken down and mobilized to produce large amount of acetyl-CoA for ketogenesis in liver, which can reduce the demand of glucose for other tissues. Acetone cannot be converted back to acetyl-CoA; therefore, they are either breathed out through the lungs or excreted in urine. "
What is the definition of Lysine Degradation?,"The degradation of L-lysine happens in liver and it is consisted of seven reactions. L-Lysine is imported into liver through low affinity cationic amino acid transporter 2 (cationic amino acid transporter 2/SLC7A2). Afterwards, L-lysine is imported into mitochondria via mitochondrial ornithine transporter 2.  L-Lysine can also be obtained from biotin metabolism. L-Lysine and oxoglutaric acid will be combined to form saccharopine by facilitation of mitochondrial alpha-aminoadipic semialdehyde synthase, and then, mitochondrial alpha-aminoadipic semialdehyde synthase will further breaks saccharopine down to allysine and glutamic acid. Allysine will be degraded to form aminoadipic acid through alpha-aminoadipic semialdehyde dehydrogenase. Oxoadipic acid is formed from catalyzation of mitochondrial kynurenine/alpha-aminoadipate aminotransferase on aminoadipic acid. Oxoadipic acid will be further catalyzed to form glutaryl-CoA, and glutaryl-CoA converts to crotonoyl-CoA, and crotonoyl-CoA transformed to 3-hydroxybutyryl-CoA. 3-Hydroxybutyryl-CoA will form Acetyl-CoA as the final product through the intermediate compound: acetoacetyl-CoA. Acetyl-CoA will undergo citric acid cycle metabolism. Carnitine is another key byproduct of lysine metabolism (not shown in this pathway). "
What is the definition of Malate-Aspartate Shuttle?,"The malate-aspartate shuttle (also known as the malate shuttle) is used by mitochondria for translocating electrons produced during glycolysis across the impermeable inner membrane for oxidative phosphorylation. This allows the hydrogen ions of the cofactor NADH produced in the cytosol to reach the electron transport chain in the mitochondria and generate ATP. The shuttle system is required because the inner membrane is impermeable to NADH and its oxidized form NAD+. NAD+/NADH does not cross the membrane, only ions (attached to malate) cross it. In this particular shuttle process, oxaloacetate on the cytoplasmic side is first reduced by NADH, creating malate and NAD+. Malate and the electrons it carries are transported into the mitochondria across the inner mitochondrial membrane, in exchange for alpha-ketoglutarate, which is transported out of the mitochondria. Once inside, the energy in malate is extracted again by reducing NAD+ to make NADH, thereby regenerating oxaloacetate. This NADH is then free to transfer its electrons to the electron transport chain. The oxaloacetate is transaminated with glutamate to make aspartate and alpha-ketoglutarate. Aspartate is returned to the cytosol by the aspartate-glutamate transporter, which moves glutamate into the mitochondria as it transports aspartate out. The net result is that NADH is transported into the mitochondria, generating 3 ATP molecules for every NADH transported in from the cytosol."
What is the definition of Nucleotide Sugars Metabolism?,"Nucleotide sugars are defined as any nucleotide in which the distal phosphoric residue of a nucleoside 5'-diphosphate is in glycosidic linkage with a monosaccharide or monosaccharide derivative. There are nine sugar nucleotides and they can be classified depending on the type of the nucleoside forming them: UDP-Glc, UDP-Gal, UDP-GlcNAc, UDP-GlcUA, UDP- Xyl, GDP-Man, GDP-Fuc and CMP-NeuNAc. Turning back now to the pathway in question, namely the nucleotide sugar metabolism pathway, it should be noted that the nucleotide sugars play an important role. Indeed, they are donors of certain important residues of sugar which are vital to glycosylation and by extension tot the production of polysaccharides. This process produces the substrates for glycosyltransferases. These sugars have several additional roles. For example, nucleotide sugars serve a vital purpose as the intermediates in interconversions of nucleotide sugars that result in the creation and activation of certain sugars necessary in the glycosylation reaction in certain organisms. Moreover, the process of glycosylation is attributed mostly (though not entirely) to the endoplasmic reticulum/golgi apparatus. Logically then, due to the important role of nucleotide sugars in glycosylation, a plethora of transporters exist which displace the sugars from their point of production, the cytoplasm, to where they are needed. In the case, the endoplasmic reticulum and golgi apparatus."
What is the definition of Pantothenate and CoA Biosynthesis?,"Panthothenate (vitamin B5) is the precursor of coenzyme A and is the prosthetic group of acyl carrier protein (ACP). Its name is derived from the Greek pantothen meaning ""from everywhere"" and small quantities of pantothenic acid are found in nearly every foodstuff. Coenzyme A (CoA) may act as an acyl group carrier to form acetyl-CoA and other related compounds and is used as a way to transport carbon atoms within the cell. CoA is important in energy metabolism for pyruvate to enter TCA cycle as acetyl-CoA, and for α-ketoglutarate to be transformed to succinyl-CoA in the cycle. CoA is also important in the biosynthesis of many important compounds such as fatty acids, cholesterol, and acetylcholine. About 85% of dietary pantothenic acid is as CoA or phosphopentetheine. In the intestinal lumen, these undergo hydrolysis to phosphopantetheine, then pantetheine. Intestinal mucosal cells have high pantetheinase activity and rapidly hydrolyze pantetheine to yield free pantothenic acid. Coenzyme A is synthesized in a five-step process from pantothenate. First, antothenate (Vitamin B5) is phosphorylated to 4'-phosphopantothenate by the enzyme pantothenate kinase, next a cysteine is added to 4'-phosphopantothenate by the enzyme phosphopantothenoylcysteine synthetase to form 4'-phospho-N-pantothenoylcysteine (PPC). In the next step, PPC is decarboxylated to 4'-phosphopantetheine by phosphopantothenoylcysteine decarboxylase. In the fourth step, 4'-phosphopantetheine is adenylylated to form dephospho-CoA by the enzyme phosphopantetheine adenylyl transferase. Finally, dephospho-CoA is phosphorylated using ATP to coenzyme A by the enzyme dephosphocoenzyme A kinase. CoA undergoes dephosphorylation, catalyzed by lysosomal acid phosphatasae to dephospho-CoA, followed by pyrophosphatase action to release 4’-phosphotantetheine and 5’AMP. Red blood cells contain pantothenic acid, pantetheine 4’-phosophate and pantetheine."
What is the definition of Phenylacetate Metabolism?,"Phenylacetate (or phenylacetic acid) metabolism involves two steps. The first step is the conversion of phenylacetate into phenylacetyl-CoA which is catalyzed by acyl-coenzyme A synthetase ACSM1 or acyl-coenzyme A synthetase ACSM2B. Coenzyme A and ATP are also involved in this first step and AMP and pyrophosphate will be generated during the first step of metabolism. In the second step, phenylacetyl-CoA and L-glutamine interacts with glycine N-acyltransferase to generate coenzyme A as well as phenylacetylglutamine, of which the latter will be excreted in the urine. Phenylacetate metabolism provides a route that facilitates the excretion of nitrogen for patients with urea cycle defects; hence, it is important for clinical purposes."
What is the definition of Pyruvaldehyde Degradation?,"This Pyruvaldehyde degradation pathway (Methylglyoxal degradation;2-oxopropanal degradation), also known as the glyoxalase system, is probably the most common pathway for the degradation of pyruvaldehyde (methylglyoxal), a potentially toxic metabolite due to its interaction with nucleic acids and other proteins. Pyruvaldehyde is formed in low concentrations by glycolysis, fatty acid metabolism and protein metabolism. Pyruvaldehyde is catalyzed by the glyoxylase system, composed of the enzymes lactoylglutathione lyase (glyoxalase I) and glyoxylase II. Glyoxalase I catalyes the isomerization of the spontaneously formed hemithioacetal adduct between glutathione and pyruvaldehyde into S-lactoylglutathione. S-lactoylglutathione is then catalyzed by glyoxalase II into D-lactic acid and glutathione. D-lactic acid is then catalyzed by an unknown quinol in the membrane to pyruvic acid, which then enters pyruvate metabolism."
What is the definition of Riboflavin Metabolism?,"Riboflavin (vitamin B2) is an important part of the enzyme cofactors FAD (flavin-adenine dinucleotide) and FMN (flavin mononucleotide).  The name ""riboflavin"" actually comes from ""ribose"" and ""flavin"".  Like the other B vitamins, riboflavin is needed for the breaking down and processing of  ketone bodies, lipids, carbohydrates, and proteins.  Riboflavin is found in many different foods, such as meats and vegetables.As the digestion process occurs, many different flavoproteins that come from food are broken down and riboflavin is reabsorbed. The reverse reaction is mediated by acid phosphatase 6. FMN can be turned into to FAD via FAD synthetase, while the reverse reaction is mediated by nucleotide pyrophosphatase.  FAD and FMN are essential hydrogen carriers and are involved in over 100 redox reactions that take part in energy metabolism. "
What is the definition of Thiamine Metabolism?,"Thiamin(e), also known as vitamin B1, is known to play a fundamental role in energy metabolism. It consists of a pyrimidine ring (2,5-dimethyl-6-aminopyrimidine) and a thiazolium ring (4-methyl-5-hydroxy ethyl thiazole) joined by a methylene bridge. Thiamine is found in a wide variety of foods at low concentrations. Yeast and pork are the most highly concentrated sources of thiamine. Cereal grains, however, are generally the most important dietary sources of thiamine, by virtue of their ubiquity. Of these, whole grains contain more thiamine than refined grains. Thiamine is released by the action of phosphatase and pyrophosphatase in the upper small intestine. At low concentrations the process is carrier mediated and at higher concentrations, absorption occurs via passive diffusion. Active transport is greatest in the jejunum and ileum (it is inhibited by alcohol consumption and by folic deficiency). The majority of thiamine in serum is bound to proteins, mainly albumin. Uptake of thiamine by cells of the blood and other tissues occurs via active transport and passive diffusion. About 80% of intracellular thiamine is phosphorylated and most is bound to proteins. Thiamine and its acid metabolites (2-methyl-4-amino-5-pyrimidine carboxylic acid, 4-methyl-thiazole-5-acetic acid and thiamine acetic acid) are excreted principally in the urine. Thiamine is mainly the transport form of the vitamin, while the active forms are phosphorylated thiamine derivatives. There are four known natural thiamine phosphate derivatives: thiamine monophosphate (ThMP), thiamine diphosphate (ThDP), also sometimes called thiamine pyrophosphate (TPP), thiamine triphosphate (ThTP), and the recently discovered adenosine thiamine triphosphate (AThTP) and adenosine thiamine diphosphate (AThDP). Thiamine monophosphate (TMP) is an intermediate to facilitate the synthesis of free thiamine to thiamine diphosphate and triphosphate. The synthesis of thiamine diphosphate (ThDP), also known as thiamine pyrophosphate (TPP) or cocarboxylase, is catalyzed by an enzyme called thiamine diphosphokinase. TPP activates decarboxylation of pyruvate in the pyruvate dehydrogenase complex. This complex is a group of enzymes and cofactors that form acetyl CoA that condenses with oxaloacetate to form citrate, the first component of the citric acid cycle."
What is the definition of Spermidine and Spermine Biosynthesis?,"The Spermidine and Spermine Biosynthesis pathway highlights the creation of these cruicial polyamines. Spermidine and spermine are produced in many tissues, as they are involved in the regulation of genetic processes from DNA synthesis to cell migration, proliferation, differentiation and apoptosis. These positiviely charged amines interact with negatively charged phosphates in nucleic acids to exert their regulatory effects on cellular processes. Spermidine originates from the action of spermidine synthase, which converts the methionine derivative S-adenosylmethionine and the ornithine derivative putrescine into spermidine 5'-methylthioadenosine. Spermidine is subsequently processed into spermine by spermine synthase in the presence of the aminopropyl donor, S-adenosylmethioninamine."
What is the definition of Taurine and Hypotaurine Metabolism?,"There is an organic acid known as Taurine, which is a derivative product of sulfhydryl amino acid (which contains sulfur), as well as cysteine.  The synthesis or metabolism in mammalian systems of this acid transpires within the pancreas in such a fashion that it utilizes a pathway known as the cysteine sulfinic acid pathway.To put this process in context, its occurrence is often seen in vivo, in hepatocytes, and is fundamental in the cyclical process of recovering bile acids from the intenstine, turning them back into salts and returning them to the bile. In essence the cysteine pathway induces a sulfhydryl group to be oxidized, creating cysteine sulfinic acid, by utilizing the appropriate enzymes (ie cysteine dioxygenase). This new acid undergoes decarboxylation creating a new compound: hypotaurine. This process goes on as Taurine now is subjected to conjugation vis a vis its amino terminal group. This includes acids such as chenodeoxycholic acid and cholic acid, and in turn the formation of bile salts occurs.Moreover, this entire process can be catalyzed via bile acid and a special amino acid N-acetyltransferase. "
What is the definition of Ubiquinone Biosynthesis?,"Ubiquinone is also known as coenzyme Q10. It is a 1,4-benzoquinone, where Q refers to the quinone chemical group, and 10 refers to the isoprenyl chemical subunits. Ubiquinone is a carrier of hydrogen atoms (protons plus electrons) and functions as an ubiquitous coenzyme in redox reactions, where it is first reduced to the enzyme-bound intermediate radical semiquinone and in a second reduction to ubiquinol (Dihydroquinone; CoQH2). Ubiquinone is not tightly bound or covalently linked to any known protein complex but is very mobile. In eukaryotes ubiquinones were found in the inner mito-chondrial membrane and in other membranes such as the endoplasmic reticulum, Golgi vesicles, lysosomes and peroxisomes. The benzoquinone portion of Coenzyme Q10 is synthesized from tyrosine, whereas the isoprene sidechain is synthesized from acetyl-CoA through the mevalonate pathway. The mevalonate pathway is also used for the first steps of cholesterol biosynthesis. The enzyme para-hydroxybenzoate polyprenyltransferase catalyzes the condensation of p-hydroxybenzoate with polyprenyl diphosphate to generate ubiquinone."
What is the definition of Sulfate/Sulfite Metabolism?,"This pathway illustrates the conversion of sulfite to sulfate (via sulfate oxidase) and subsequent generation of adenylylsulfate (APS) via 3'-phosphoadenosine 5'-phosphosulfate synthase 2. APS is converted to phosphoadenylyl-sulfate (PAPS) via adenylylsulfate kinase. APS can also be regenerated from PAPS by 3'(2'), 5'-bisphosphate nucleotidase 1. PAPS is eventually converted to adenosine bisophosphate (PAP) through the action of several different enzymes including aryl sulfotransferase, chondroitin 4-sulfotransferase 13 and estrone sulfotransferase. The metabolism pathway in question is important for many reasons. Recall, that the sulfite ion is in fact the conjugate base of sulfurous acid. Moreover, this ion is found naturally in one of the worlds most popular beverages, wines. Beyond its natural occurence, sulfite ion had the property of stopping fermentation. As such, the addition of it to products such as wine can be used either as a preservative or to stop the fermentation process at a moment which is of interest. Finally, this preservation property goes beyond merely wines, and finds utility in dried fruits, potatoes, etc."
What is the definition of Phytanic Acid Peroxisomal Oxidation?," Phytanic acid, a branched chain fatty acid, is an important component of fatty acid intake, occuring in meat, fish and dairy products.  Due to its methylation, it cannot be a substrate for acyl-CoA dehydrogenase and cannot enter the mitochondrial beta oxidation pathway.  Phytanic acid is instead activated to its CoA ester form by a CoA synthetase to phytanoyl-CoA, where it can begin the first cycle of alpha oxidation.  Phytanoyl-CoA is a substrate for a specific alpha-hydroxylase (Phytanoyl-CoA hydroxylase), which adds a hydroxyl group to the α-carbon of phytanic acid, creating the 19-carbon homologue, pristanic acid.  Pristanic acid then undergoes further metabolism through beta oxidation. "
What is the definition of Phenylalanine and Tyrosine Metabolism?,"In man, phenylalanine is an essential amino acid which must be supplied in the dietary proteins.  Once in the body, phenylalanine may follow any of three paths.  It may be (1) incorporated into cellular proteins, (2) converted to phenylpyruvic acid, or (3) converted to tyrosine.  Tyrosine is found in many high protein food products such as soy products, chicken, turkey, fish, peanuts, almonds, avocados, bananas, milk, cheese, yogurt, cottage cheese, lima beans, pumpkin seeds, and sesame seeds.  Tyrosine can be converted into L-DOPA, which is further converted into dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline).  Depicted in this pathway is the conversion of phenylalanine to phenylpyruvate (via amino acid oxidase or tyrosine amino transferase acting on phenylalanine), the incorporation of phenylalanine and/or tyrosine into polypeptides (via tyrosyl tRNA synthetase and phenylalyl tRNA synthetase) and the conversion of phenylalanine to tyrosine via phenylalanine hydroxylase.  This reaction functions both as the first step in tyrosine/phenylalanine catabolism by which the body disposes of excess phenylalanine, and as a source of the amino acid tyrosine.  The decomposition of L-tyrosine begins with an α-ketoglutarate dependent transamination through the tyrosine transaminase to para-hydroxyphenylpyruvate.  The next oxidation step catalyzed by p-hydroxylphenylpyruvate-dioxygenase creates homogentisate.  In order to split the aromatic ring of homogentisate, a further dioxygenase, homogentistate-oxygenase, is required to create maleylacetoacetate.  Fumarylacetate is created by the action maleylacetoacetate-cis-trans-isomerase through rotation of the carboxyl group created from the hydroxyl group via oxidation.  This cis-trans-isomerase contains glutathione as a coenzyme.  Fumarylacetoacetate is finally split via fumarylacetoacetate-hydrolase into fumarate (also a metabolite of the citric acid cycle) and acetoacetate (3-ketobutyroate). "
What is the definition of Histidine Metabolism?," Histidine is unique in that its biosynthesis is inherently linked to the pathways of nucleotide formation.  The biosynthesis of histidine in adults begins with the condensation of ATP and PRPP (phosphoribosyl pyrophosphate) to form N-5-phosphoribosyl 1-pyrophosphate (phosphoribosyl-ATP).  It is also worth noting that PRPP is the starting point for purine and pyrimidine biosynthesis.  Subsequent histidine biosynthetic steps (from phosphoribosyl-ATP onwards) likely take place in the intestinal microflora.  Elimination of the phosphate and the opening of the ring in phosphoribosyl-ATP forms phosphoribosyl-forminino-5-aminoimidazole-4-carboxamide ribonucleotide (phosphoribosyl-formimino-AICAR-phosphate).  This is subsequently converted to 5-phosphoribulosyl-forminino-5-aminoimidazole-4-carboxamide ribonucleotide.  Cleavage of this intermediate results in the formation of imidazole glyercol phosphate and AICAR (aminoimidazolecarboxamide ribonucleotide) with glutamine playing a role as an amino group donor.  AICAR is recycled through the purine pathway while the imidazole glycerol phosphate is converted to imidazole acetal phosphate.  Transamination yields histidinol phosphate which is converted to histidinol and finally to histidine.  Histidine catabolism begins with release of the α-amino group catalyzed by histidase, leading to the deaminated product, urocanate.  Urocanate is converted to 4-imidazolone-5-propionate via the action of urocanate hydratase.  The latter product is then converted to N-formiminoglutamte via the action of imidazolone propionase.  The enzyme formiminotransferase cyclodeaminase then removes the formimino group to yield glutamate.  Because the end product of histidine catabolism is glutamate this makes histidine one of the glucogenic amino acids.  Another key feature of histidine catabolism is that it serves as a source of ring nitrogen to combine with tetrahydrofolate (THF), producing the 1-carbon THF intermediate known as N5-formiminoTHF.  The latter reaction is one of two routes to N5-formiminoTHF.  Decarboxylation of histidine in the intestine by bacteria gives rise to histamine.  Similarly, histamine arises in many tissues by the decarboxylation of histidine, which in excess causes constriction or dilation of various blood vessels.  Once histamine is generated it can be converted to several breakdown products including N-methylhistamine, imidazole acetaldehyde, methylimidazole acetaldehyde and methylimidazole-acetic acid.  Histidine is also a precursor for carnosine biosynthesis (via carnosine synthase), with beta-alanine being the rate limiting precursor.   Anserine can be synthesized either from carnosine via carnosine N-methyltransferase or from 1-methylhistidine via carnosine synthase.   Inversely, cytosolic non-specific dipeptidase catalyzes the synthesis of 1-methylhistidine from anserine. "
What is the definition of Arachidonic Acid Metabolism?,"This pathway describes the production and subsequent metabolism of arachidonic acid, an omega-6 fatty acid. In resting cells arachidonic acid is present in the phospholipids (especially phosphatidylethanolamine and phosphatidylcholine) of membranes of the body’s cells, and is particularly abundant in the brain. Typically a receptor-dependent event, requiring a transducing G protein, initiates phospholipid hydrolysis and releases the fatty acid into the intracellular medium. Three enzymes mediate this deacylation reaction including phospholipase A2 (PLA2), phospholipase C (PLC), and phospholipase D (PLD). Once released, free arachidonate has three possible fates: 1) reincorporation into phospholipids, 2) diffusion outside the cell, and 3) metabolism. Arachidonate metabolism is carried out by three distinct enzyme classes: cyclooxygenases, lipoxygenases, and cytochrome P450’s. Specifically, the enzymes cyclooxygenase and peroxidase lead to the synthesis of prostaglandin H2, which in turn is used to produce the prostaglandins, prostacyclin, and thromboxanes. The enzyme 5-lipoxygenase leads to 5-HPETE, which in turn is used to produce the leukotrienes, hydroxyeicosatetraenoic acids (HETEs) and lipoxins. Some arachidonic acid is converted into midchain HETEs, omega-chain HETEs, dihydroxyeicosatrienoic acids (DHETs), and epoxyeicosatrienoic acids (EETs) by cytochrome P450 epoxygenase hydroxylase activity. Several products of these pathways act within neurons to modulate the activities of ion channels, protein kinases, ion pumps, and neurotransmitter uptake systems, affecting processes such as cellular proliferation, inflammation, and hemostasis. The newly formed eicosanoids may also exit the cell of origin and bind to G-protein-coupled receptors present on nearby neurons or glial cells."
What is the definition of Androgen and Estrogen Metabolism?,"This pathway describes the inactivation and catabolism of male (androgen) and female (estrogen) hormones. Many steroid hormones are transformed by sulfatases, dehydrogenases and glucuronide transferases to enhance their solubility and to facilitate their elimination. Inactivation refers to the metabolic conversion of a biologically active compound into an inactive one. Peripheral inactivation (e.g. by liver enzymes) is required to ensure steady-state levels of plasma androgens and estrogens. Specifically, if an androgen or estrogen is to act as a "" chemical signal "", its half-life in the circulation must be limited, so that any change in secretion rate is immediately reflected by a change in its plasma concentration. But hormone inactivation can also occur in target tissues, notably after the hormone has triggered the relevant biological effects in order to ensure termination of hormone action. The main site of peripheral androgen/estrogen inactivation and catabolism is the liver, but some catabolic activity also occurs in the kidneys. Inactive androgens and estrogens are mainly eliminated as urinary (mostly conjugated) metabolites. This elimination requires conversion to hydrophilic compounds in order to ensure their solubility in biological fluids at rather high concentrations. Depending on the structure of the starting steroid there may be: 1) Reduction of a double bond at C-4 and reduction of an oxo(keto) group at C-3 to a secondary alcoholic group; 2) Reduction of an oxo group at C-20 to a secondary alcoholic group; 3) Oxidation of a 17ß-hydroxyl group; 4) Further hydroxylations at various positions of the steroid nucleus (e.g. 7-hydroxylation of 5a-reduced androgens) or 5) Conjugation (sulphate and/or glucuronide derivatives)."
What is the definition of Glucose-Alanine Cycle?,"The glucose-alanine cycle—also referred to in the literature as the Cahill cycle or the alanine cycle—involves muscle protein being degraded to provide more glucose to generate additional ATP for muscle contraction. It allows pyruvate and glutamate to be transported out of muscle tissue to the liver where gluconeogenesis takes place to supply the muscle tissue with more glucose as mentioned previously. To initiate the cycle, muscle and tissues that catabolize amino acids for fuel generate amino groups—most commonly in the form of glutamate—through the process of transamination. These amino groups are transferred via alanine aminotransferase to pyruvate (a product of glycolysis) to form alanine and alpha-ketoglutarate. Alanine subsequently moves through the circulatory system to the liver where the reaction previously catalyzed by alanine aminotransferase is reversed to produce pyruvate. This pyruvate is converted into glucose through the process of gluconeogenesis which subsequently is transported back to the muscle tissue. Meanwhile, glutamate dehydrogenase in the mitochondria catabolizes glutamate into ammonium. Ammonium moves on to form urea in the urea cycle."
What is the definition of Vitamin K Metabolism?,"Vitamin K describes a group of lipophilic, hydrophobic vitamins that exist naturally in two forms (and synthetically in three others): vitamin K1, which is found in plants, and vitamin K2, which is synthesized by bacteria. Vitamin K is an important dietary component because it is necessary as a cofacter in the activation of vitamin K dependent proteins. Metabolism of vitamin K occurs mainly in the liver. In the first step, vitamin K is reduced to its quinone form by a quinone reductase such as NAD(P)H dehydrogenase. Reduced vitamin K is the form required to convert vitamin K dependent protein precursors to their active states. It acts as a cofactor to the integral membrane enzyme vitamin K-dependent gamma-carboxylase (along with water and carbon dioxide as co-substrates), which carboxylates glutamyl residues to gamma-carboxy-glutamic acid residues on certain proteins, activating them. Each converted glutamyl residue produces a molecule of vitamin K epoxide, and certain proteins may have more than one residue requiring carboxylation. To complete the cycle, the vitamin K epoxide is returned to vitamin K via the vitamin K epoxide reductase enzyme, also an integral membrane protein. The vitamin K dependent proteins include a number of important coagulation factors, such as prothrombin. Thus, warfarin and other coumarin drugs act as anticoagulants by blocking vitamin K epoxide reductase."
What is the definition of Phospholipid Biosynthesis?,"This pathway describes the synthesis of the common phospholipids, including phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol and cardiolipins. Phospholipids can be synthesized by two mechanisms. One utilizes a CDP-activated polar head group for attachment to the phosphate of phosphatidic acid. The other utilizes CDP-activated 1,2-diacylglycerol and an inactivated polar head group. Phospholipids are synthesized in the ER membrane from cytosolic precursors. Two fatty acids linked to coenzyme A (CoA) carriers are first joined to glycerol-3-phosphate, yielding phosphatidic acid, which is simultaneously inserted into the membrane. A phosphatase then converts phosphatidic acid to diacylglycerol. The attachment of different polar head groups to diacylglycerol then results in formation of phosphatidylcholine, phosphatidylethanolamine, or phosphatidylserine. Phosphatidylinositol is formed from phosphatidic acid, rather than from diacylglycerol. Initially, most phospholipids have a saturated fatty acid on C-1 and an unsaturated fatty acid on C-2 of the glycerol backbone. However, the fatty acid distribution at the C–1 and C–2 positions of glycerol within phospholipids is continually in flux, owing to phospholipid degradation and the continuous phospholipid remodeling that occurs while these molecules are in membranes. In many cases the acyl group which was initially transferred to glycerol, by the action of the acyl transferases, is not the same acyl group present in the phospholipid when it resides within a membrane. The remodeling of acyl groups in phospholipids is the result of the action of phospholipase A1 (PLA1) and phospholipase A2 (PLA2). The most commonly added alcohols (serine, ethanolamine and choline) also contain nitrogen that may be positively charged, whereas, glycerol and inositol do not."
What is the definition of Lactose Synthesis?,"Lactose synthesis occurs only in the mammary glands, producing lactose (4-O-B-D-galactosylpyranosyl-a-D-glucopyranoside), the major sugar in milk. Lactose is created by joining two monosaccarides with a B1,4 glycosidic bond. Glucose is first converted to UDP-galactose via the enzyme galactose-1-phosphate uridylyltransferase. UDP-galactose is then transported into the Golgi by the UDP galactose translocator, an antiporter which uses facilitated transport to move UDP galactose into the Golgi and exports UMP. Once inside the Golgi, the UDP galactose and glucose (which moves into the golgi via the GLUT-1 transporter) become substrates for the lactose synthase enzyme complex, comprised of the enzymatic subunit, galactosyltransferase with its regulatory subunit, Alpha-lactalbumin. Lactose synthase creates lactose through bonding galactose from UDP to glucose through a glycosidic bond. Although GT is found in many tissues in the body, Alpha-lactalbumin is only found on the inner surface of the Golgi in the mammary glands, limiting lactose production to the mammaries."
What is the definition of Steroid Biosynthesis?,"The steroid biosynthesis (or cholesterol biosynthesis) pathway is an anabolic metabolic pathway that produces steroids from simple precursors. It starts with the mevalonate pathway, where acetyl-CoA and acetoacetyl-CoA are the first two building blocks. These compounds are joined together via the enzyme hydroxy-3-methylgutaryl (HMG)-CoA synthase to produce the compound known as hydroxy-3-methylgutaryl-CoA (HMG-CoA). This compound is then reduced to mevalonic acid via the enzyme HMG-CoA reductase. It is important to note that HMG-CoA reductase is the protein target of many cholesterol-lowering drugs called statins (PMID: 12602122). The resulting mevalonic acid (or mevalonate) is then phosphorylated by the enzyme known as mevalonate kinase to form mevalonate-5-phosphate, which is then phosphorylated again by phosphomevalonate kinase to form mevolonate-5-pyrophsophate. This pyrophosphorylated compound is subsequently decarboxylated via the enzyme mevolonate-5-pyrophsophate decarboxylase to form isopentylpyrophosphate (IPP). IPP can also be isomerized (via isopentenyl-PP-isomerase) to form dimethylallylpyrophosphate (DMAPP). IPP and DMAPP can both donate isoprene units, which can then be joined together to make farnesyl and geranylgeranyl intermediates. Specifically, three molecules of IPP condense to form farnesyl pyrophosphate through the action of the enzyme known as geranyl transferase. Two molecules of farnesyl pyrophosphate then condense to form a molecule known as squalene by the action of the enzyme known as squalene synthase in the cell’s endoplasmic reticulum. The enzyme oxidosqualene cyclase then cyclizes squalene to form lanosterol. Lanosterol is a tetracyclic triterpenoid, and serves as the framework from which all steroids are derived. 14-Demethylation of lanosterol by a cytochrome P450 enzyme known as CYP51 eventually yields cholesterol. Cholesterol is the central steroid in human biology. It can be obtained from animal fats consumed in the diet or synthesized de novo (as described above). Cholesterol is an essential constituent of lipid bilayer membranes (where it forms cholesterol esters) and is the starting point for the biosynthesis of steroid hormones, bile acids and bile salts, and vitamin D. Steroid hormones are mostly synthesized in the adrenal gland and gonads. They regulate energy metabolism and stress responses (via glucocorticoids such as cortisol), salt balance (mineralocorticoids such as aldosterone), and sexual development and function (via androgens such as testosterone and estrogens such as estradiol). Bile acids and bile salts (such as taurocholate) are mostly synthesized in the liver. They are released into the intestine and function as detergents to solubilize dietary fats. Cholesterol is the main constituent of atheromas. These are the fatty lumps found in the walls of arteries that occur in atherosclerosis and, when ruptured, can cause heart attacks."
"What is the definition of Valine, Leucine, and Isoleucine Degradation?","Valine, isoleuciine, and leucine are essential amino acids and are identified as the branched-chain amino acids (BCAAs).  The catabolism of all three amino acids starts in muscle and yields NADH and FADH2 which can be utilized for ATP generation.  The catabolism of all three of these amino acids uses the same enzymes in the first two steps.  The first step in each case is a transamination using a single BCAA aminotransferase, with α-ketoglutarate as the amine acceptor.  As a result, three different α-keto acids are produced and are oxidized using a common branched-chain α-keto acid dehydrogenase (BCKD), yielding the three different CoA derivatives.  Isovaleryl-CoA is produced from leucine by these two reactions, alpha-methylbutyryl-CoA from isoleucine, and isobutyryl-CoA from valine.  These acyl-CoA’s undergo dehydrogenation, catalyzed by three different but related enzymes, and the breakdown pathways then diverge.  Leucine is ultimately converted into acetyl-CoA and acetoacetate; isoleucine into acetyl-CoA and succinyl-CoA; and valine into propionyl-CoA (and subsequently succinyl-CoA).  Under fasting conditions, substantial amounts of all three amino acids are generated by protein breakdown.  In muscle, the final products of leucine, isoleucine, and valine catabolism can be fully oxidized via the citric acid cycle; in the liver, they can be directed toward the synthesis of ketone bodies (acetoacetate and acetyl-CoA) and glucose (succinyl-CoA).  Because isoleucine catabolism terminates with the production of acetyl-CoA and propionyl-CoA, it is both glucogenic and ketogenic.  Because leucine gives rise to acetyl-CoA and acetoacetyl-CoA, it is classified as strictly ketogenic. "
What is the definition of Purine Metabolism?,"Purines are heterocyclic aromatic organic compounds, consisting of a pyrimidine ring fused to an imidazole ring. Purines, including substituted purines, are the most widely distributed kind of nitrogen-containing heterocycle in nature. The two most important purines are adenine and guanine. Other notable purines are hypoxanthine, xanthine, theobromine, caffeine, uric acid and isoguanine. Purines are found in a number of other important biomolecules, such as ATP, GTP, cyclic AMP, NADH, and coenzyme A. This pathway depicts a number of processes including purine nucleotide biosynthesis, purine degradation and purine salvage. The major site of purine nucleotide synthesis is in the liver. Synthesis of the purine nucleotides begins with PRPP and leads to the first fully formed nucleotide, inosine 5'-monophosphate (IMP). IMP synthesis begins with 5-phospho-α-ribosyl-1-pyrophosphate, PRPP. Through a series of reactions utilizing ATP, tetrahydrofolate (THF) derivatives, glutamine, glycine and aspartate this pathway yields IMP. The rate limiting reaction is catalyzed by glutamine PRPP amidotransferase which drives the reaction with PRPP and glutamine yielding 5-phosphoribosylamine (PRA). 5-phosphoribosylamine is converted to glycinamide ribotide (GAR) then to formyglycinamide ribotide (FGAR). This set of reactions is catalyzed by a trifunctional enzyme containing GAR synthetase, GAR transformylase and AIR synthetase. FGAR is converted to formylglycinamidine-ribonucleotide (FGAM) by formylglycinamide synthase. FGAM is then converted by aminoimidzaole ribotide synthase to 5-aminoimidazole ribotide (AIR) then carboxylated by aminoimidazole ribotide carboxylase to carboxyaminoimidazole ribotide (CAIR). CAIR is then converted to succinylaminoimidazole carboxamide ribotide (SAICAR) by succinylaminoimidazole carboxamide ribotide synthase followed by conversion to AICAR (via adenylsuccinate lyase) then to FAICAR (via aminoimidazole carboxamide ribotide transformylase). FAICAR is finally converted to inosine monophosphate (IMP) by IMP cyclohydrolase. Because of the complexity of this synthetic process, the purine ring is actually composed of atoms derived from many different molecules. The N1 atom arises from the amine group of Asp, the C2 and C8 atoms originate from formate, the N3 and N9 atoms come from the amide group of Gln, the C4, C5 and N7 atoms come from Gly and the C6 atom comes from CO2. IMP represents a branch point for purine biosynthesis, because it can be converted into either AMP or GMP through two distinct reaction pathways. AMP is generated from IMP via adenylsuccinate synthetase (which adds aspartate) and adenylsuccinate lyase. GMP is generated via the action of IMP dehydrogenase and GMP synthase. Catabolism of purine nucleotides ultimately leads to the production of uric acid. Beginning from AMP, the enzymes AMP deaminase and nucleotidase work in concert to generate inosine. Alternately, AMP may be dephosphorylate by nucleotidase and then adenosine deaminase (ADA) converts the free adenosine to inosine. The enzyme purine nucleotide phosphorylase (PNP) converts inosine to hypoxanthine, while xanthine oxidase converts hypoxanthine to xanthine and finally to uric acid. GMP and XMP can also be converted to uric acid via the action of nucleotidase, PNP, guanine deaminase and xanthine oxidase. The synthesis of nucleotides from the purine bases and purine nucleosides takes place in a series of steps known as the salvage pathways. The free purine bases, adenine, guanine, and hypoxanthine, can be reconverted to their corresponding nucleotides by phosphoribosylation. Two key transferase enzymes are involved in the salvage of purines: adenosine phosphoribosyltransferase (APRT), which catalyzes the conversion of adenine to AMP and hypoxanthine-guanine phosphoribosyltransferase (HGPRT), which catalyzes the conversion of hypoxanthine to IMP."
What is the definition of Vitamin B6 Metabolism?,"As is commonly known there are many vitamins, the vitamin B complex group being one of the most well known. An important vitamin B complex group vitamin is vitamin B6, which is water-soluble. Moreover, this vitamin comes in various forms, one of which is an active form, known by the name pyridoxal phosphate or PLP. PLP serves as cofactor in a variety of reactions including from amino acid metabolism, (in particular in reactions such as transamination, deamination, and decarboxylation). To complicate matters however, there are in fact seven alternate forms of this same vitamin. These include pyridoxine (PN), pyridoxine 5’-phosphate (PNP), pyridoxal (PL), pyridoxamine (PM), pyridoxamine 5’-phosphate (PMP), 4-pyridoxic acid (PA), and the aforementioned pyridoxal 5’-phosphate (PLP). One of these forms, PA, is in fact a catabolite whose presence is found in excreted urine. For a person to absorb some of these active forms of vitamin B6 such as PLP or PMP they must first be dephosphorylized. This done via an alkaline enzyme phosphatase. There are a wide variety of biproducts from the metabolism in question, most of which find there ways into the urine and from there are excreted. One such biproduct is 4-pyridoxic acid. In fact this last biproduct is found in such large quantities that estimates of vitamin B6 metabolism birproducts show that 4-pyridoxic acid is as much as 40-60% of all the biproducts.Of course, it is not the only product of metabolism. Others include,include pyridoxal, pyridoxamine, and pyridoxine."
What is the definition of Pyruvate Metabolism?,"Pyruvate is an intermediate compound in the metabolism of fats, proteins, and carbohydrates. It can be formed from glucose via glycolysis or the transamination of alanine. It can be converted into Acetyl-CoA to be used as the primary energy source for the TCA cycle, or converted into oxaloacetate to replenish TCA cycle intermediates. Pyruvate can also be used to synthesize carbohydrates, fatty acids, ketone bodies, alanine, and steroids. In conditions of inssuficient oxygen or in cells with few mitochondria, pyruvate is reduced to lactate in order to re-oxidize NADH back into NAD+Pyruvate participates in several key reactions and pathways. In glycolysis, phosphoenolpyruvate (PEP) is converted to pyruvate by pyruvate kinase in an highly exergonic and irreversible reaction. In gluconeogenesis, pyruvate carboxylase and PEP carboxykinase are needed to catalyze the conversion of pyruvate to PEP. In fatty acid synthesis, the pyruvate dehydrogenase complex decarboxylates pyruvate to produce acetyl-CoA. In gluconeogenesis, the carboxylation by pyruvate carboxylase produces oxaloacetate. The fate of pyruvate depends on the cell energy charge. In cells or tissues with a high energy charge pyruvate is directed toward gluconeogenesis, but when the energy charge is low pyruvate is preferentially oxidized to CO2 and H2O in the TCA cycle, with generation of 15 equivalents of ATP per pyruvate. The enzymatic activities of the TCA cycle are located in the mitochondrion. When transported into the mitochondrion, pyruvate encounters two principal metabolizing enzymes: pyruvate carboxylase (a gluconeogenic enzyme) and pyruvate dehydrogenase (PDH). With a high cell-energy charge, acetyl-CoA, is able allosterically to activate pyruvate carboxylase, directing pyruvate toward gluconeogenesis. When the energy charge is low CoA is not acylated, pyruvate carboxylase is inactive, and pyruvate is preferentially metabolized via the PDH complex and the enzymes of the TCA cycle to CO2 and H2O."
What is the definition of Pentose Phosphate Pathway?,"The pentose phosphate pathway—also referred to in the literature as the phosphogluconate pathway, the hexose monophosphate shunt, or the pentose phosphate shunt—is involved in the generation of NADPH as well as pentose sugars. Of the total cytoplasmic NADPH used in biosynthetic reactions, a significant proportion of it is generated through the pentose phosphate pathway. Ribose 5-phosphate is also another essential product generated by this pathway which is employed in nucleotide synthesis. The pentose phosphate pathway is also involved in the digestive process as the products of nucleic acid catabolism can be metabolized through the pathway (pentose sugars are usually yielded in the breakdown) while the carbon backbones of dietary carbohydrates can be converted into glycolytic/gluconeogenic intermediates. The pentose phosphate pathway is interconnected to the glycolysis pathway through the shared use of three intermediates: glucose 6-phosphate, glyceraldehyde 3-phosphate, and fructose 6-phosphate.The pathway can be described as eight distinct reactions (see below) and is separated into an oxidative phase and a non-oxidative phase. Reactions 1-3 form the oxidative phase and generate NADPH and pentose 5-phosphate. Reactions 4-8 form the non-oxidative phase and converts pentose 5-phosphate into other pentose sugars such as ribose 5-phosphate, but generates no NADPH. The eight reactions are as follows: reaction 1 converts glucose 6-phosphate into D-glucono-1,5-lactone 6-phosphate with NADPH formation; reaction 2 converts D-glucono-1,5-lactone 6-phosphate into 6-phospho-D-gluconate; reaction 3 converts 6-phospho-D-gluconate into ribulose 5-phosphate with NADPH formation; reaction 4 converts ribulose 5-phosphate into xylulose 5-phosphate; reaction 5 converts ribulose 5-phosphate into ribose 5-phosphate; reaction 6 rearranges ribose 5-phosphate and xylulose 5-phosphate to form sedoheptulose 7-phosphate and glyceraldehyde 3-phosphate; reaction 7 rearranges sedoheptulose 7-phosphate and glyceraldehyde 3-phosphate to form erythrose 4-phosphate and fructose 6-phosphate; and reaction 8 rearranges xylulose 5-phosphate and erythrose 4-phosphate to form glyceraldehyde 3-phosphate and fructose-6-phosphate."
What is the definition of Methionine Metabolism?,"Methionine metabolism in mammals consists of 2 pathways, the methionine cycle and the transsulfuration sequence. These pathways share 3 common reactions with both including the conversion of methionine to S-adenosylmethionine (SAM),the utilization of SAM in diverse transmethylation reactions yielding a methylated product plus S-adenosylhomocysteine, and the cleavage of S-adenosylhomocysteine to yield homocysteine and adenosine. The transulfuration reactions that produce cysteine from homocysteine and serine also produce α-ketobutyrate, the latter being converted first to propionyl-CoA and then via a 3-step process to succinyl-CoA. Regulation of the methionine metabolic pathway is based on the availability of methionine and cysteine. If both amino acids are present in adequate quantities, SAM accumulates and is a positive effector on cystathionine synthase, encouraging the production of cysteine and α-ketobutyrate (both of which are glucogenic). However, if methionine is scarce, SAM will form only in small quantities, thus limiting cystathionine synthase activity."
What is the definition of Primary Hyperoxaluria Type I?,"Type I primary hyperoxaluria (Glycolicaciduria) is caused by mutation in the gene encoding alanine-glyoxylate aminotransferase (AGXT). AGXT normally catalyzes the reaction from L-serine and pyruvate to 3-hydroxypyruvate and L-alanine and the reaction from L-alanine and glyoxylate to pyruvate and glycine. A defect in AGXT results in accumulation of glycolic acid, glyoxylic acid, and oxalate in urine. Symptoms include hematuria, myocarditis, nephrocalcinosis, peripheral neuropathy, and renal failure."
What is the definition of Pyruvate Carboxylase Deficiency?,"Pyruvate carboxylase deficiency is caused by mutation in the pyruvate carboxylase gene. Serine—pyruvate aminotransferase catalyzes the reaction of serine and pyruvate to produce 3-hydroxypyruvate and L-alanine, as well as the reaction from L-alanine and glyodxylate to pyruvate and glycine. A defect in this results in accumulation of ammonia, glucose and pyruvate in blood; proline, lysine, citrulline, and alanine in plasma; and 2-oxoglutaric acid, fumaric acid, ketone bodies and succinate in urine. Symptoms include ataxia, lactic acidosis, mental retardation, metabolic acidosis, siezures, and dyspnea."
What is the definition of 17-beta Hydroxysteroid Dehydrogenase III Deficiency?,"Defects in 17-beta hydroxysteroid dehydrogenase III (HSD17B3) are the cause of male pseudohermaphrodism with gynecomastia. These individuals have unambiguous female external genitalia at birth, but fail to menstruate at the time of expected puberty and instead virilize as evidenced by growth of the phallus. A defect in HSD17B3 causes accumulation of dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEA-S) as well as androstenedione in plasma."
What is the definition of beta-Ketothiolase Deficiency?,"beta-Ketothiolase Deficiency (2-Methyl-3-Hydroxybutyric Acidemia; Mitochondrial Acetoacetyl-CoA Thiolase Deficiency; MAT Deficiency; T2 Deficiency; 3-KTD Deficiency; 3-Ketothiolase Deficiency) is an autosomal recessive disease caused by a mutation in the HADHB gene which codes for beta-ketathiolase. A deficiency in this enzyme results in accumulation of ammonia and ketone bodies in blood; and 2-methyl-3-hydroxybutyric acid, 2-methylacetoacetic acid, 3-hydroxybutyric acid, tiglylglycine, and ketone bodies in urine. Symptoms include ketosis, seizures, organic acids in urine, and hyperammonemia. Treatment includes a low protein diet and L-carnitine.h3. h2."
What is the definition of 2-Methyl-3-hydroxybutyryl-CoA Dehydrogenase Deficiency?,"2-Methyl-3-hydroxybutyryl CoA dehydrogenase deficiency (Hydroxyl-CoA dehydrogenase deficiency; MHBD) is a rare inborn disease of metabolism caused by a mutation in the HSD17B10 gene which codes for 3-hydroxyacyl-CoA dehydrogenase type-2. A deficiency in this enzyme results in accumulation of L-lactic acid in blood, spinal fluid, and urine; 2-ethylhydracrylic acid, 2-methyl-3-hydroxybutyric acid, and tiglylglycine in urine. Symptoms include cerebal atrophy, motor and mental retardation, overactivity and behavior issues, seizures and progressive neurological defects leading to early death. Treatment includes a high carbohydrate and low protein diet."
What is the definition of Propionic Acidemia?,"Propionic acidemia (Ketotic hyperglycinemia) is caused by mutation in the genes encoding propionyl-CoA carboxylase, PCCA or PCCB. The break down of Propionyl-CoA is catalyzed by Propionyl-CoA carboxylase (PCC). Propionyl-CoA plays an important role in amino acid metabolism. A mutation in this enzyme causes accumulation of ammonia and propionylcarnitine (C3) in the blood; carnitine , glutamine, glycine, and propionic acid in the plasma; 3-hydroxypropionic acid, 3-hydroxyvaleric acid, 5-oxoproline, acylcarnitin, glycine, methylcitric acid, propionylglycine and tiglylcine in the urine. Symptoms include cardio myopathy, growth retardation, hypothermia, ketosis, neutropenia, strokelike episodes, pyloric stenosis and spastic diplegia/quadriplegia."
What is the definition of 3-Hydroxy-3-methylglutaryl-CoA Lyase Deficiency?,"3-Hydroxy-3-methylglutaryl-CoA lyase deficiency (3-Hydroxy-3-methylglutaric acidemia; Leucine metabolism, defect in, HMG-CoA lyase deficiency) is an autosomal recessive disease caused by a mutation in the HMGCL gene which codes for hydroxymethylglutaryl-CoA lyase. A deficiency in this enzyme results in accumulation of 3-hydroxymethylglutaric acid, 3-hydroxyisovaleric acid, 3-methylcrotonylglycine and 3-methylglutaconic acid (cis and trans form), and methylglutaric acid in urine; and ammonia in blood. Symptoms include cardiomyopathy, dehydration, hypotonia, lactic acidosis, and pancreatitis. Treatment includes a low-fat, low-protein, high-carbohydrate diet."
What is the definition of Maple Syrup Urine Disease?,"Maple Syrup Urine Disease (Branched-chain alpha-keto acid dehydrogenase deficiency, MSUD) is caused by a deficiency of the branched-chain alpha-keto acid dehydrogenase enzyme complex (BCKDH), which normally degrades the branched chain amino acids leucine, isoleucine, and valine. The disease is characterized in an infant by the presence of sweet-smelling urine, with an odor similar to that of maple syrup. Increased amounts of valine, leucine and isoleucine and their toxic byproducts accumulate in the blood, plasma, and urine. Symptoms include ataxia, encephalopathy, ketosis, mental retardation, seizures, and a maple syrup or caramel odor."
What is the definition of 3-Methylcrotonyl-CoA Carboxylase Deficiency Type I?,"3-Methylcrotonyl-Coenzyme A Carboxylase Deficiency Type I (3-MCC Deficiency; MCCD Type I; Methylcrotonylglycinuria Type I; 3-Methylcrotonylglycinuria I) is caused by a defect in the MCCC1 and MCCC2 genes. 3-methylcrotonyl-coenzyme A carboxylase plays an essential role in breaking down proteins from the diet. Specifically, the enzyme is responsible for the fourth step in processing leucine. If a mutation in the MCCC1 or MCCC2 gene reduces or eliminates the activity of 3-methylcrotonyl-CoA carboxylase, the body is unable to process leucine properly. As a result, toxic byproducts of leucine processing build up to harmful levels, damaging the brain and nervous system. Symptoms include recurring episodes of vomiting and diarrhea, lethargy, hypotonia, seizures, and coma."
What is the definition of 3-Methylglutaconic Aciduria Type I?,"3-Methylglutaconic aciduria type 1 (3-Methylglutaconicaciduria; Aciduria, 3-methylglutaconic type I) is an autosomal recessive disease caused by a mutation in the AUH gene which codes for methylglutaconyl-CoA hydratase. A deficiency in this enzyme results in accumulation of 3-hydroxyisovaleric acid, 3-methylglutaconic acid, and methylglutaric acid in urine. Symptoms include hypoglycemia, low birth weight, coma, seizures, and mental retardation. Treatment includes a low protein diet."
What is the definition of 3-Methylglutaconic Aciduria Type III?,"3-Methylglutaconic aciduria type 3 (Costeff syndrome; Optic atrophy plus syndrome) is an autosomal recessive disease caused by a deficiency in the OPA3 code which does for optic atrophy 3 protein. A deficiency of this enzyme results in accumulation of 3-methylglutaconic acid and methylglutaric acid. Symptoms include ataxia, dysarthria, optic atrophy, and neurological deterioration."
What is the definition of Methylmalonate Semialdehyde Dehydrogenase Deficiency?,"Methylmalonate Semialdehyde Dehydrogenase Deficiency (MMSDH Deficiency; Aldehyde Dehydrogenase 6 Family, Member A1; ALDH6A1 Deficiency)is caused by a defect in methylmalonate semialdehyde dehydrogenase, which catalyzes the irreversible oxidative decarboxylation of malonate and methylmalonate semialdehydes to acetyl- and propionyl-CoA, respectively. A defect in methylmalonate semialdehyde dehydrogenase causes accumulation of 3-Aminoisobutyric acid, 3-Hydroxyisobutyric acid, 3-hydroxypropionic acid, beta-Alanine, lactate, and methylmalonic acid in urine. Symptoms inclue failure to thrive, large liver, mental and motor retardation and vomiting."
What is the definition of Methylmalonic Aciduria?,"Methylmalonic acidemia cause defects (Methylmalonaciduria due to methylmalonic CoA mutase; Acidemia, methylmalonic; MMA) in the metabolic pathway where methylmalonyl-coenzyme A (CoA) is converted into succinyl-CoA by the enzyme methylmalonyl-CoA mutase. Defects in the enzyme Methylmalonyl-CoA mutase causes accumulation of ammonia in blood; methylmalonic acid in plasma; creatinine and uric acid in serum; 3-Aminoisobutyric acid, 3-Hydroxypropionic acid, 3-Hydroxyvaleric acid, glycine, methylcitric acid and methylmalonic acid in urine; and methylmalonic acid in spinal fluid. Symptoms include anemia, dehydration, growth retardation, nephrosis, respiratory distress and metabolic acidosis."
What is the definition of 4-Hydroxybutyric Aciduria/Succinic Semialdehyde Dehydrogenase Deficiency?,"4-Hydroxybutyric Aciduria/Succinic Semialdehyde Dehydrogenase Deficiency (SSADH; Gamma-hydroxybutyric acidemia) inhibits the formation of succinate from GABA. This deficiency results in urinary excretion of 4-hydroxybutyric acid. In vivo proton MR also indicates elevated GABA levels as compared with an age-matched control. Symptoms include ataxia, chorea or athetosis, motor retardation, seizures, macrocephaly and delayed or abnormal speech development."
What is the definition of Homocarnosinosis?,"Homocarnosinosis is caused by an inherited defect in serum carnosinase, which converts homocarnosine to GABA (gamma aminobutyric acid). A defect in serum carnosinase causes accumulation of the brain specific dipeptide homocarnosine (Hca), in the CSF and brain. Symptoms include hypotonia, mental retardation, retinitis pigmentosa and spastic diplegia/quadriplegia."
What is the definition of Hyperinsulinism-Hyperammonemia Syndrome?,"Hyperinsulinism-hyperammonemia syndrome (HHS; Glutamate dehydrogenase 1; GLUD1), an inherited condition, is caused by a defect in the GLUD1 gene which codes for mitochondrial glutamate dehydrogenase 1. It is a mitochondrial matrix enzyme, with a key role in the nitrogen and glutamate (Glu) metabolism and the energy homeostasis. An excessive activity of this enzyme results in high insulin and ammonia levels in blood; decrease level of glucose in blood. Symptoms and signs include shakiness, weakness, seizure, rapid pulse and confusion. Maintain normoglycemia is essencial to prevent neurologic damage. Some medications can be used to suppress insulin secretion."
What is the definition of Glutathione Synthetase Deficiency?,"Glutathione Synthetase Deficiency (5-Oxoprolinuria; Pyroglutamic Aciduria) is caused by a defect in the GSS gene which codes for glutathione synthetase. Glutathione synthetase is the second enzyme in the glutathione biosynthesis pathway. It catalyses the condensation of gamma-glutamylcysteine and glycine, to form glutathione. A defect in this enzyme results in accumulation of pyroglutamic acid and gamma-glutamylcysteine in urine and blood; decrease level of glutathione in erythrocytes; increase urinary excretion of 5-oxoproline. Glutathione synthetase deficiency can be classified into three types: mild, moderate and severe. Mild glutathione synthetase deficiency usually results in the destruction of red blood cells (hemolytic anemia). Rarely, affected people also excrete large amounts of a compound called 5-oxoproline in their urine (5-oxoprolinuria). This compound builds up when glutathione is not processed correctly in cells. Individuals with moderate glutathione synthetase deficiency may experience symptoms beginning shortly after birth including hemolytic anemia, 5-oxoprolinuria, and elevated acidity in the blood and tissues (metabolic acidosis). In addition to the features present in moderate glutathione synthetase deficiency, individuals affected by the severe form of this disorder may experience neurological symptoms. These problems may include seizures; a generalized slowing down of physical reactions, movements, and speech (psychomotor retardation); mental retardation; and a loss of coordination (ataxia). Some people with severe glutathione synthetase deficiency also develop recurrent bacterial infections."
What is the definition of 5-Oxoprolinuria?,"5-Oxoprolinuria (5-Oxoprolinase deficiency) is a result of a defect in the gamma-glutamyl cycle due to either 5-oxoprolinase or glutathione synthetase deficiency. In the case of glutathione synthetase deficiency, the glycine is not incorporated into gamma-glutamylcysteine. In the case of 5-oxoprolinase, however, pyroglutamic acid accumulates. Symptoms include anemia, mental retardation, metabolic acidosis, respiratory distress and urolithiasis."
What is the definition of Adenosine Deaminase Deficiency?,"Adenosine deaminiase deficiency (immunodeficiency) is an autosomal recessive disease caused by a muation in the ADA gene which codes for adenosine deaminase. A deficiency in this enzyme results in immunodeficiency and a decreased concentration of lymphocytes in blood. Symptoms include diarrhea, severe or recurrent infections, vomiting and early onset in children, infants and newborns. Treatment includes bone-marrow transplants and enzyme replacement therapy."
What is the definition of Adenylosuccinate Lyase Deficiency?,"Adenylosuccinate Lyase Deficiency. (Adenylosuccinase Deficiency ; Adenylosuccinate monophosphate lyase deficiency) is a rare autosomal recessive disease caused by a mutation in the ADSL gene which codes for adenylosuccinate lyase. A deficiency in this enzyme results in accumulation of succinyladenosine in plasma, spinal fluid, and urine. Symptoms, which present at birth, include hyptonia, seizures, mental retardation, and encephalopathy. Treatment includes allopurinol."
What is the definition of Gout or Kelley-Seegmiller Syndrome?,"Gout, or Kelley-Seegmiller syndrome, is caused by a partial defect in the HPRT1 gene which codes for hypoxanthine-guanine phosphoribosyltransferase. Hypoxanthine-guanine phosphoribosyltransferase is an enzyme in purine metabolism. Its primarily functions to salvage purines from degraded DNA to renewed purine synthesis. In this role, it acts as a catalyst in the reaction between guanine and phosphoribosyl pyrophosphate (PRPP) to form GMP. A partial deficiency in this enzyme causes overproduction of uric acid, therefore it results in accumulation of uric acid in serum and increase urinary excretion of uric acid. Symptoms and signs include excruciating, sudden, unexpected, burning pain, as well as swelling, redness, warmth, and stiffness in the affected joint, usually in the great toe, tophi in the helix or antihelix of the ear, along the ulnar surface of the forearm, in the olecranon bursa, or in other tissues. Treatment has three objectives: manage symptoms of acute attacks, prevent acute attacks, and reduce serum uric acid."
What is the definition of Lesch-Nyhan Syndrome (LNS)?,"Lesch-Nyhan Syndrome (LNS; Hypoxanthin guanine phosphoribosyltransferase deficiency) is caused by a complete defect in the HPRT1 gene which codes for hypoxanthine-guanine phosphoribosyltransferase. Hypoxanthine-guanine phosphoribosyltransferase is an enzyme in purine metabolism. Its primarily functions to salvage purines from degraded DNA to renewed purine synthesis. In this role, it acts as a catalyst in the reaction between guanine and phosphoribosyl pyrophosphate (PRPP) to form GMP. A complete deficiency in this enzyme causes overproduction of uric acid, therefore it results in accumulation of uric acid in serum and increase urinary excretion of uric acid. Symptoms and signs include severe gout and kidney problems, poor muscle control, and moderate mental retardation. These complications usually appear in the first year of life. A striking feature of LNS is self-mutilating behaviors, characterized by lip and finger biting, that begin in the second year of life. Neurological symptoms include facial grimacing, involuntary writhing, and repetitive movements of the arms and legs similar to those seen in Huntington’s disease. Treatment for LNS is symptomatic. Gout can be treated with allopurinol to control excessive amounts of uric acid. Kidney stones may be treated with lithotripsy, a technique for breaking up kidney stones using shock waves or laser beams. There is no standard treatment for the neurological symptoms of LNS. Some may be relieved with the drugs carbidopa/levodopa, diazepam, phenobarbital, or haloperidol."
What is the definition of Molybdenum Cofactor Deficiency?,"Molybdenium cofactor deficiency (Sulfite oxidase deficiency) is caused by mutations in the genes MOCS1 and MOCS2 in the formation of molybdenum cofactor. A molybdenum-containing cofactor is essential to the function of 3 enzymes: sulfite oxidase, xanthine dehydrogenase, and aldehyde oxidase. Xanthine dehydrogenase is a molybdenum-containing hydroxylase involved in the oxidative metabolism of purines. Defects in this enzyme cause accumulation of hypoxanthine,, s-s-sulfocysteine, taurine, and xanthine in the urine. Symptoms include hemorrhage, cerebral atrophy, encephalopathy, lactic acidosis, nystagmus, spastic diplegia/quadriplegia, and vomiting."
What is the definition of Xanthine Dehydrogenase Deficiency (Xanthinuria)?,"The rare genetic disorder, Xanthinuria (also referred to as xanthine oxidase deficiency) results from a deficiency of the enzyme xanthine oxidase. This enzyme deficiency causes the accumulation of: xanthine in the plasma, uric acid in serum or hypoxanthine, uric acid and xanthine in the urine. The disorder has symptoms including arthralgia, hematuria, mental retardation, stomatisis, and urolithiasis."
What is the definition of Purine Nucleoside Phosphorylase Deficiency?,"Purine nucleoside phosphorylase deficiency (Nucleoside phosphorylase; Immunodeficiency) is a rare disease causing severe immunodeficiency. The disease is caused by a mutation in the enzyme purine nucleoside phosphorylase. The enzyme is necessary for purine breakdown. The mutation causes deoxy-GTP (dGTP) to accumulate which causes T-cell toxicity. The disease results in accumulation of guanosine, inosine, and uric acid in serum; and orotic acid in some cases in the urine. Symptoms include anemia, ataxia, hypotonia, lymphopenia, mental retardation, and tremor or twitching."
What is the definition of AICA-Ribosiduria?,"AICA-ribosiduria is a metabolic disease caused by a defect in final steps of purine de novo biosynthesis. This defect is caused by a mutation in the ATIC which codes for bifunctional purine biosynthesis protein PURH. A deficiency in this enzyme results in accumulation of 5-aminoimidazole-4-carboxamide in urine. Symptoms include mental retardation, epilepsy, dysmorphic features, and congenital blindness."
What is the definition of Prolidase Deficiency (PD)?,"Prolidase deficiency is an autosomal recessive disorder. The enzyme prolidase cleaves iminodipeptides with N-terminal proline or hydroxyproline. Collagen has high levels of iminoacids therefore, these dipeptidases are important for collagen metabolism. A defect in this enzyme causes accumulation of imidodipeptides in urine. Symptoms include skin lesions, anemia, dysmorphism, mental retardation, and ptosis (drooping eyelid)."
What is the definition of Arginine: Glycine Amidinotransferase Deficiency (AGAT Deficiency)?,"Arginine: Glycine Amidinotransferase Deficiency (AGAT Deficiency, Creatine Deficiency Syndrome, Creatine Deficiency due to AGAT Deficiency, GATM Deficiency) is caused by mutation in the GATM gene, which codes for L-arginine:glycine amidinotransferase, which catalyzes the reaction between L-arginine and glycine, transferring an amidino group from L-arginine to glycine, producing L-ornithine and guanidinoacetate, a precursor of creatine. A defect in this enzyme causes a decrease in concentration of creatine and guanidinoacetate in plasma and urine. Symptoms include mental and motor retardation, seizures, and delayed or abnormal speech development."
What is the definition of Hyperprolinemia Type II?,"Hyperprolinemia (prolinemia Type II, HPII, prolinuria) is caused by mutation in the pyrroline-5-carboxylate dehydrogenase gene (P5CDH), which encodes pyrroline-5-carboxylate dehydrogenase. This enzyme assists in the metabolism of pyrroline-5-carboxylate, converting it to the amino acid glutamine. The conversion between proline and glutamine, and the reverse reaction controlled by different enzymes, are essential factors required to maintain proper metabolism and protein production. A defect in this enyzme causes accumulation of proline in plasma; ornithine in serum; and glycine, hydroxyproline and proline in urine. Symptoms include mental retardation, acute and chronic renal failure and seizures."
What is the definition of Hyperprolinemia Type I?,"Hyperprolinemia type I (HPI, proline oxidase deficiency) is caused by mutation in the proline dehydrogenase gene (PRODH), which codes for proline dehydrogenase (proline oxidase). This enzyme converts proline to delta-1-pyrroline-5-carboxylate. A defect in proline dehydrogenase causes accumulation of proline in plasma, and glycine, hydroxyproline, and proline in urine. Symptoms include mental retardation, renal cysts, and seizures."
What is the definition of Prolinemia Type II?,"Prolinemia Type II is caused by mutation in the pyrroline-5-carboxylate dehydrogenase gene (P5CDH) mitochondrial matrix NAD-dependent dehydrogenase. This dehydrogenase is a catalyst for converting pyrroline-5-carboxylate to glutamate in the proline degradation pathway. An enzyme defect causes accumulation of glycine, hydroxyproline and proline in the urine, ornithine in the serum and proline in plasma. Symptoms include mental retardation, acute and chronic renal failure, and seizures."
What is the definition of Guanidinoacetate Methyltransferase Deficiency (GAMT Deficiency)?,"Guanidinoacetate Methyltransferase Deficiency (Creatine-Deficiency-Syndrome) is a rare autosomal recessive disease caused by a mutation in the GAMT gene which codes for guanidinoacetate N-methyltransferase. A deficiency in this enzyme results in accumulation of 3-methylglutaconic acid in urine; guanidoacetic acid in urine and serum. Decreased concentrations of creatine are found in serum and urine; and creatinine in plasma, spinal fluid, and urine. Symptoms, which present at birth, include failure to thrive, mental and motor retardation, hyoptonia, and seizures. Treatment includes arginine-restricted diet, sodium benzoate, and L-ornithine hydrochlorate."
What is the definition of Ornithine Aminotransferase Deficiency (OAT Deficiency)?,"Ornithine Aminotransferase Deficiency, (OAT Deficiency, Ornithine Keto Acid Aminotransferase Deficiency, OKT Deficiency, Ornithine-Delta-Aminotransferase Deficiency, Hyperornithinemia With Gyrate Atrophy Of Choroid And Retina; Hoga Gyrate Atrophy, Ornithine Aminotransferase) is caused by a defect in the gene that codes for ornithine-delta-aminotransferase, which catalyzes the major catalytic reaction for ornithine. A defect in this enzyme causes accumulation of ornithine. Symptoms include tunnel vision, night blindness, myopia, and progressive vision loss."
What is the definition of Aromatic L-Aminoacid Decarboxylase Deficiency?,"Aromatic L-Aminoacid Decarboxylase Deficiency (DOPA decarboxylase; DDC) is an autosomal recessive disease caused by a mutation in the DDC gene which codes for aromatic-L-aminoacid decarboxylase. A deficiency in this enzyme results in accumulation of 3-methoxytyrosine, 5-hydroxy-L-tryptophan, and L-Dopa in plasma, spinal fluid, and urine; 3-methoxytyramine and dopamine in urine. It also results in decreased concentrations of homovanillic acid, S-adenosylmethionine, and 5-hydroxytryptophol in spinal fluid; and epinephrine, norepinephrine in plasma. Symptoms include temperature instability, hypotonia, mental and motor retardation, and cerebral atrophy."
What is the definition of Isovaleric Aciduria?,"Isovaleric acidemia (IVA) is caused by mutation in the isovaleryl CoA dehydrogenase gene. Isovaleryl CoA dehydrogenase is part of the acyl-CoA dehydrogenase family and is involved in the catabolism of leucine. A defect in this enzyme causes accumulation of ammonia, ketone bodies, Isovaleryl/2-Methylbutyrylcarnitine (C5) in blood; carnitine in plasma; creatinine, and glucose in serum; 3-Hydroxybutyric acid, 3-Hydroxyisovaleric acid, 4-Hydroxyvaleric acid, acetyltryptophan, glycine, acylcarnitin, isovalerylasparagine, isovalerylglycine, isovaleryllysine, isovalerylhistidine and isovaleryltryptophan in urine. Symptoms include encephalopathy, ketosis, metabolic acidosis, pancreatitis, sweaty feet odor, and thrombocytopenia."
What is the definition of Biotinidase Deficiency?,"Biotinidase deficiency (Multiple carboxylase deficiency) is an autosomal recessive disease caused by a mutation in the BTD gene which codes for biotinidase. A deficiency in this enzyme results in accumulation of ammonia and ketone bodies in blood; 3-hydroxyisovaleric acid in plasma, spinal fluid, and urine; hydroxypropionic acid, 2-hydroxybutyric acid, 3-Hydroxybutyric acid, and citric acid in spinal fluid; and 3-methylcrotonylglycine, hydroxypropionic acid, and L and D-lactic acid in urine. Symptoms, which can present from birth into adulthood include hypotonia, ketosis, hyperammonemia, motor retardation, coma, and seborrhoic skin rash. Treatment includes biotin."
What is the definition of Canavan Disease?,"Canavan Disease (Canavan-Van Bogaert-Bertrand Disease; Aminoacylase 2 Deficiency; Spongy Degeneration of the Central Nervous System; Aspartoacylase Deficiency; ASP Deficiency; ACY2 Deficiency; ASPA) is a rare autosomal recessive disease caused by a defect in the ASPA gene which codes for aspartoacylase. A deficiency in this enzyme results in accumulation of N-Acetyl-L-aspartic acid in plasma, spinal fluid, and urine. Symptoms, which present at birth, include myclonus, irritability, hypotonia, motor retardation, and poor head control. The neurological complications are due to demyelination of neurons and leukodystrophy. Premature death often results, though lithium citrate can be used as a treatment."
What is the definition of Hypoacetylaspartia?,Hypoacetylaspartia is a result of a defect in L-aspartate-N-acetyltransferase which results in a strongly decreased concentration of N-acetyl-L-aspartic acid according to the in vivo spectrum of the brain.
What is the definition of Smith-Lemli-Opitz Syndrome (SLOS)?,"The autosomal recessive disorder Smith-Lemli-Opitz Syndrome (SLOS; SLO Syndrome; RSH; Rutledge Lethal Multiple Congenital Anomaly, Syndrome; Polydactyly, Sex Reversal, Renal Hypoplasia, and Unilobar Lung; Lethal Acrodysgenital Syndrome) is characterized by disordered steroid biosynthesis. It results from a mutation in the DHCR7 gene coding for the enzyme sterol delta-7-reducatase. This enzyme catalyzes the production of cholesterol by reducing the C7-C8 double bond of 7-dehydrocholesterol (7-DHC). SLOS causes the accumulation of 7-dehydrocholesterol and 8-dehydrocholesterol, and a decrease of cholesterol in plasma; and 3-methylglutaconic acid in urine. All patients with SLOS have mental retardation, and symptoms include ambiguous genitalia, hypotonia, microcephaly, syndactyly, limb abnormalities and deformities and polydactyly."
What is the definition of CHILD Syndrome?,"CHILD Syndrome, (Congenital Hemidysplasia with Icthyosiform Erythroderma and Limb Defects; Ichthyosiform Eruthroderma, Unilateral, with Epsilateral Malformations, Especially Absence Deformity of Limbs) is caused by a mutation in the gene encoding NADH steroid dehydrogenase-like protein (NSDHL). A defect in sterol-4 alpha-carboxylate 3-dehydrogenase, which normally catalyzes the reaction 3-beta-hydroxy-4-beta-methyl-5-alpha-cholest-7-ene-4-alpha-carboxylate + NAD+ = 4-alpha-methyl-5-alpha-cholest-7-en-3-one + CO2 + NADH, causes accumulation of 8(9)cholestenol and 8-dehydrocholesterol in plasma. Symptoms of CHILD syndrome include hearing defects, hemidysplasia, unilateral hypomelia, ichthyosiform nevi, limb abnormalities, lung hypoplasia, and punctate calcifications."
What is the definition of Desmosterolosis?,"Desmosterolosis is caused by a mutation in the DHCR24 gene, which codes for the enzyme 24-dehydrocholesterol reductase, which catalyzes the reduction of the delta-24 double bond of sterol intermediates. A defect in 24-dehydrocholesterol reductase causes accumulation of desmosterol in plasma. Symptoms include cleft palate, clubfoot, dysmorphism, mental and motor retardation, and speech development."
"What is the definition of Chondrodysplasia Punctata II, X-Linked Dominant (CDPX2)?","Chondrodysplasia Punctata 2, X Linked Dominant (CDPX2; CPDXD; CPXD; Conradi-Hunermann Syndrome; Happle Syndrome; Conradi-Hunermann-Happle Syndrome is caused by a mutation in the gene encoding delta(8)-delta(7) sterol isomerase emopamil-binding protein (EBP). EBP contains the code for the enzyme 3-beta-hydroxysteroid-Delta(8),Delta(7)-isomerase, which normally catalyzes the conversion of Delta(8)-sterols to their corresponding Delta(7)-isomers. A defect in this enzyme causes accumulation of 8-dehydrocholesterol and 8(9)cholestenol in the plasma. Symptoms include alopecia, dysmorphism, hyperkeratosis, ichthyosis, kyphoscoliosis, limb abnormalities and deformities, and mental retardation."
What is the definition of Lysosomal Acid Lipase Deficiency (Wolman Disease)?,"Lysosomal Acid Lipase Deficiency (Wolman disease) is caused by a defect in lysosomal acid lipase (LIPA, or LAL), otherwise known as acid cholesteryl ester hydrolase, which is coded for by a gene (LIPA) on chromosome 10. Two major disorders, the severe infantile-onset Wolman disease and the milder late-onset cholesteryl ester storage disease (CESD), may be caused by mutations in separate parts of the LIPA gene. Wolman disease is characterized by increased transaminases in serum, and increased cholesteryl esters and triglycerides in various tissues. Symptoms include anemia, diarrhea, failure to thrive, enlarged liver, malabsorption, steatorrhea and abdominal pain."
What is the definition of Cystathionine beta-Synthase Deficiency?,"Cystathionine Beta-Synthase Deficiency (CBS Deficiency; Homocystinuria) is an autosomal recessive disease caused by a mutation in the CBS gene which codes for cystathionine beta-synthase. A deficiency in this enzyme results in accumulation of L-cystathionine, homocysteine, and L-homocystine in plasma and urine; and L-methionine and ornithine in plasma. Symptoms include osteoporosis, myopia, fatty-liver, mental retardation, and early death. Treatment includes folic acid, vitamin B6, vitamin B12, and a methionine-restricted diet."
What is the definition of Hypermethioninemia?,"Hypermethioninemia is caused by a defect in the AHCY gene which codes for Adenosylhomocysteinase. converts the S-adenosyl homocysteine into the compound homocysteine. Homocysteine may be converted back to methionine or into another amino acid, cysteine. A defect in this enzyme results in accumulation of methionine and cysteine in blood. People with hypermethioninemia often do not show any symptoms. Some individuals with hypermethioninemia exhibit learning disabilities, mental retardation, and other neurological problems; delays in motor skills such as standing or walking; sluggishness; muscle weakness; liver problems; unusual facial features; and their breath, sweat, or urine may have a smell resembling boiled cabbage."
What is the definition of S-Adenosylhomocysteine (SAH) Hydrolase Deficiency?,"S-Adenosylhomocysteine (SAH) Hydrolase Deficiency (Hypermethioninemia, familial) results from AHCY gene defect. AHCY codes for S-adenosylhomocysteine hydrolase (SAH). SAH catalyzes the hydrolysis of S-adenosylhomocysteine to adenosine and homocysteine. S-adenosylhomocysteine is a byproduct of S-adenosylmethionine-dependent methyltransferases. This hydrolysis reaction is a common way to eliminate S-adenosylhomocysteine in eukaryotes. SAH Deficiency causes accumulation of guanidinoacetate, homocysteine, methionine, s-adenosylhomocysteine and s-adenosylmethionine in plasma, and methionine in spinal fluid. Symptoms include cerebral atrophy, dysmorphism, strabismus, jaundice, mental and motor retardation."
What is the definition of Glycine N-Methyltransferase Deficiency?,Glycine N-methyltransferase deficiency (GNMT deficiency) is caused by mutation in the GNMT gene (606628). Glycine N-methyltransferase catalyzes the synthesis of N-methylglycine (sarcosine) from glycine using S-adenosylmethionine (AdoMet) as the methyl donor. GNMT acts as an enzyme to regulate the ratio of S-adenosylmethionine to S-adenosylhomocysteine (AdoHcy) and participates in the detoxification pathway in liver cells. A defect in this enzyme causes accumulation of methionine in the plasma and transaminases in the serum. Symptoms include hepatomegaly.
What is the definition of Methylenetetrahydrofolate Reductase Deficiency (MTHFRD)?,"Methylenetetrahydrofolate reductase deficiency (MTHFRD; Homocystinuria due to defect of n(5,10)-methylene THF deficiency) is caused by a defect in the MTHFR gene which codes for methylenetetrahydrofolate reductase. Methylenetetrahydrofolate reductase catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, a co-substrate for homocysteine remethylation to methionine. A defect in this enzyme results in accumulation of homocysteine and methionine in both plasma and urine. Some of the symptoms and signs include mental retardation, withdrawal, hallucinations, delusions, muscle weakness. Some patients remain asymptomatic until adulthood."
What is the definition of Methionine Adenosyltransferase Deficiency?,"Methionine adenosyltransferase (MAT; Hypermethioninemia; MAT I/III deficiency) deficiency is caused by mutations in the MAT1A gene which causes isolated hypermethioninemia. MAT catalyzes the formation of adenosylmethionine from methionine and ATP. Adenosylmethionine is an important methyl donor in most transmethylation reactions. MAT dificiency is characterized by increased homocysteine and methionine levels in plasma; and accumulation of methionine in urine. Symptoms include dystonia, mental retardation and unusual odor."
What is the definition of Ethylmalonic Encephalopathy?,"Ethylmalonic Encephalopathy (Epema Syndrome; EE) is a rare autosomal recessive disorder caused by a mutation in the ETHE1 gene which codes for protein ETHE1. A deficiency of this protein inhibits proper energy production in mitochondria and a deficiency in cytochrome c oxidase. This results in accumulation of 2-methylbutyrylglycine, N-butyrylglycine, isobutyrylglycine, isovalerylglycine, and methylsuccinic acid in urine. Concentrations of L-carnitine are reduced in plasma. Symptoms, which present at birth, include peripheral neuropathy, seizures, microcephaly, and hypotonia lead to premature death. Treatment includes riboflavin and L-carnitine."
What is the definition of Glutaric Aciduria Type I?,"Glutaric Aciduria Type 1 is a rare autosomal recessive disease caused by a mutation in the GCDH which codes for glutaryl-CoA dehydrogenase. A deficiency in this enzyme results in accumulation of 3-hydroxybutyric acid, 3-hydroxyglutaric acid, glutaconic acid, glutaric acid, and ketone bodies in urine. Symptoms include encephalopathy, grimacing, dystonia, metabolic acidosis, and hygroma. Treatment includes a low-protein diet, L-carnitine, riboflavin, and anticonvulsants."
What is the definition of Short-Chain Acyl-CoA Dehydrogenase Deficiency (SCAD Deficiency)?,"Short Chain Acyl CoA Dehydrogenase Deficiency (SCAD Deficiency) is caused by mutation in the gene encoding short-chain acyl-CoA dehydrogenase, an enzyme which normally breaks down short chain fatty acids. SCADD causes accumulation of ammonia in blood; butyrylcarnitine(C4) in plasma; adipic acid, butyrylglycine, ethylmalonic acid; hexanoylglycine and methylsuccinic acid in urine. Symptoms include hypoglycemia, hypotonia, microcephaly, failure to thrive, lactic acidosis, peripheral neuropathy, and vomiting."
What is the definition of GABA-Transaminase Deficiency?,"GABA-Transaminase Deficiency (Gamma-amino butyric acid transaminase deficiency; GABA-T) is caused by a defect in the gene coding for gamma-aminobutyrate transaminase, which is responsible for catabolism of gamma-aminobutyric acid (GABA), an important, mostly inhibitory neurotransmitter in the central nervous system, into succinic semialdehyde. The active enzyme is a homodimer of 50-kD subunits complexed to pyridoxal-5-phosphate. GABAT is present in several tissues in addition to brain and is most active in liver. GABA-T catalyzes the conversion of gamma-aminobutyrate and L-beta-aminoisobutyrate to succinate semialdehyde and methylmalonate semialdehyde, respectively. This enzyme can also convert delta-aminovalerate and beta-alanine. Defects in GABA-T cause accumulation of beta-alanine and gamma aminobutyric acid in plasma and spinal fluid, as well as accumulation of homocarnosine in spinal fluid. Symptoms include hyperreflexia, hypotonia, lethargia, macrosomia, mental retardation, and seizures."
What is the definition of gamma-Glutamyltransferase Deficiency?,"Gamma-Glutamyltransferase Deficiency is an autosomal recessive disorder caused by a mutation in the GGT1 gene which codes for gamma-glutamyltranspeptidase 1. A deficiency in this enzyme results in accumulation of L-cysteine, gamma-glutamylcysteine, and glutathione in urine. Symptoms, which present at birth, include tall stature, psychosis, and mental retardation."
What is the definition of Saccharopinuria/Hyperlysinemia II?,"Saccharopinuria (also known as: saccharopinemia, saccharopine dehydrogenase deficiency, and alpha-aminoadipic semialdehyde synthase deficiency) is caused by a partial deficiency of aminoadipic semialdehyde synthase (AASS) enzyme and causes an increase in saccharopine in the urine. Saccharopinuria is another form of hyperlysinemia.  AASS has lysine ketoglutarate reductase (LKR) and saccharopine dehydrogenase (SDH) activity. AASS acts in the first 2 steps in lysine degradation. A defect in this enzyme results in accumulation of citrulline, lysine and saccharopin in the plasma; lysine in the spinal fluid; and citrulline, lysine and saccharopine in the urine. Symptoms include growth and mental retardation."
What is the definition of Histidinemia?,"Histidinemia (Histidine Ammonia-Lyase Deficiency; HAL Deficiency; Histidase Deficiency; HIS Deficiency) is an autosomal recessive disease caused by a mutation in the HAL gene which codes for hisitidine ammonia-lyase. A deficiency in this enzyme results in accumulation of L-histidine in serum, spinal fluid, and urine; histamine in plasma and urine; and imidazoleacetic acid, imidazolactic acid, and 1-methylhistamine in urine. Symptoms include organic acids in urine, mental retardation, and delayed speech development. Treatment includes a low-histamine diet."
What is the definition of Lactic Acidemia?,"Increased lactic acid concentrations in urine or serum can be a result of many metabolic disorders but also of other origin (infections, etc.). Respiratory chain defects account for most of the metabolic causes of lactic acid accumulation. Often alanine is also high. A urine spectrum indicating an increased lactic acid and alanine concentration is shown."
What is the definition of Leigh Syndrome?,"Leigh’s disease (Encephalopathy), a form of Leigh syndrome, also known as Subacute Necrotizing Encephalomyelopathy (SNEM), is a rare neurometabolic disorder that affects the central nervous system. It is an inherited disorder that usually affects infants between the age of three months and two years, but, in rare cases, teenagers and adults as well. In the case of the disease, mutations in mitochondrial DNA (mtDNA) or in nuclear DNA (gene SURF11 and some COX assembly factors) cause degradation of motor skills and eventually death. Leigh syndrome is caused by defects in many mitocondrial and nuclear encoded genes involved in energy metabolism, resulting in accumulation of L-Alanine and in plasma and urine. Symptoms include dystonia, ataxia, encephalopathy, muscle weakness, and tremor or twitching."
What is the definition of Pyruvate Decarboxylase E1 Component Deficiency (PDHE1 Deficiency)?,"Pyruvate Decarboxylase E1 Component Deficiency is caused by a defect in the PDHA1 gene which codes for mitochondrial pyruvate dehydrogenase E1 component subunit alpha, somatic form. This is a homotetrameric enzyme that catalyses the decarboxylation of pyruvic acid to acetaldehyde and carbon dioxide. A defect in this enzyme results in accumulation of lacate and pyruvate. Symptoms and signs include severe lactic acidosis in the newborns that usually leading to death, hypotonic, lethargic, seizures, mental retardation and spasticity."
What is the definition of Pyruvate Dehydrogenase Complex Deficiency?,"Pyruvate dehydrogenase complex deficiency results from a mutation in the E1-alpha polypeptide gene (PDHA1). PDHA1 encodes the pyruvate dehydrogenase complex (PDC) a critical complex that converts pyruvate from glycolysis to acetyl CoA for the citric acid cycle. This conversion step links glycolysis and the citric acid cycle. A defect in this complex causes accumulation of lactate and pyruvate in the blood; lactate and pyruvic acid in the spinal fluid; and lactate in the urine. Symptoms include lactic and metabolic acidosis, motor retardation, dystonia, growth and mental retardation, and respiratory distress."
What is the definition of Leukotriene C4 Synthesis Deficiency?,"Leukotriene C4 synthetase deficiency is caused by a defect in the enzyme leukotriene C4 synthetase (LTC4S). This enzyme catalyzes the synthesis of leukotriene C4 (LTC4) through conjugation of LTA4 with reduced glutathione (GSH), which is synthesized by glutathione synthetase. Leukotriene C4 and its receptor-binding metabolites LTD4 and LTE4 are cysteinyl leukotrienes that are potent lipid mediators of tissue inflammation. In general, leukotrienes are potent proinflammatory mediators synthesized from membrane-derived arachidonic acid after activation of certain granulocytes. A defect in LTC4 results in decreased concentrations of cysteinyl leukotrienes LTC4, LTD4 and LTE4 in plasma, spinal fluid and urine. Symptoms include early death, failure to thrive, motor retardation, microcephaly, and progressive neurological defect."
What is the definition of Phenylketonuria?,"Phenylketonuria (Hyperphenylalaninemia ; HPA ; PKU) is an autosomal recessive genetic disorder characterized by a deficiency in the enzyme hepatic phenylalanine hydroxylase (PAH). PAH is necessary to metabolize the amino acid phenylalanine to the amino acid tyrosine. When PAH is deficient, phenylalanine accumulates and is converted into phenylpyruvate, which is detected in the urine. Left untreated, this condition can cause problems with brain development, leading to progressive mental retardation and seizures."
What is the definition of Tyrosinemia Type 2 (or Richner-Hanhart Syndrome)?,"Tyrosinemia II also known as Richner-Hanhart syndrome is an autosomal recessive disorder caused by a mutation in the TAT gene the encodes for tyrosine aminotransferase. A defect in this enzyme causes excess tyrosine to accumulate in the blood and urine, tyrosine crystals to form in the cornea, and increased excretion in the urine of 4-hydroxyphenylpyruvic acid, hydroxyphenyllactic acid, and p-hydroxyphenylacetic acid. Symptoms commonly appear in early childhood and include: mental retardation, photophobia (increased sensitivity to light), excessive tearing, eye redness and pain and skin lesions of the palms and soles. The patient is treated with restriction of dietary phenylalanine and tyrosine. Sometimes a tyrosine degradation inhibitor is also used to prevents the formation of fumarylacetoacetate from tyrosine. Trosinemia II is commonly misdiagnosed as herpes simplex keratitis. "
What is the definition of Tyrosinemia Type 3 (TYRO3)?,"Tyrosinemia type 3, one of the three types of tyrosinemia, is a rare disorder with only a few reported cases. Tyrosinemia type 3 results from a defect in the HPD gene which codes for 4-hydroxyphenylpyruvate dioxygenase. 4-Hydroxyphenylpyruvate dioxygenase plays a role in the catabolism of tyrosine by catalyzing the conversion of 4-hydroxyphenylpyruvate to homogentisate. A defect in this enzyme causes tyrosine and phenylalanine to accumulate in the blood resulting in increased excretion of tyrosine in the urine. Tyrosinemia type 3 symptoms include: seizures, mental retardation and intermittent ataxia (occasional loss of balance and coordination). "
What is the definition of Refsum Disease?,"Adult Refsum Disease (Classic Refsum Disease; Phytanic Acid Oxidase Deficiency; Heredopathia Atactica Polyneurtiformis; Hereditary Motor and Sensory Neuropathy IV; HSMN4; Adult Refsum Disease I; Adult Refsum Disease II), can be caused by mutations in the PHYH (or PAHX) gene, which encodes Phytanoyl-CoA hydroxylase (, the first enzyme in the Phytanic Acid Peroxisomal Oxidation pathway) on chromosome 10 (adult Refsum disease I), and by mutation of the PEX7 gene. A defect in phytanoyl-CoA hydroxylase results in accumulation of phytanic acid in the plasma, as well as low levels of pristanic acid due to the inability for phytanic acid to undergo alpha and beta oxidation. Symptoms include anosmia, ataxia, nystagmus, neurological deterioration and peripheral neuropathy. Adult Refsum disease is distinctly different from Infantile Refsum disease both genetically and phenotypically. Infantile Refsum disease  involves mutations of the PEX1, PEX2 and PEX26 genes."
What is the definition of Sialuria or French Type Sialuria?,"Sialuria is caused by mutation in the gene encoding uridinediphosphate-N-acetylglucosamine 2-epimerase (UDP-GlcNAc 2-epimerase, which causes an excessive synthesis of sialic acid (N-acetylneuraminic acid, NeuAc). This causes accumulation of sialic acid in the urine. Symptoms of sialuria include hepatosplenomegaly, hypotonia, frequent upper respiratory infections, gastroenteritis and seizures."
What is the definition of Salla Disease/Infantile Sialic Acid Storage Disease?,"Both the infantile and Finnish (Salla disease; 604369) forms of sialuria are due to mutation in the SLC17A5 gene, which encodes a vesicular excitatory amino acid transporter (VEAT) with dual physiologic functions. When present in synaptic vesicles in the central nervous system, sialin is responsible for vesicular storage and subsequent exocytosis of aspartate and glutamate. When present in lysosomes, it acts as an H+-coupled sialic acid exporter. Mutations in this transporter cause accumulation of free sialic acid in the urine. Symptoms include seizures, mental, growth, and motor retardation, nystagmus, and speech development."
What is the definition of Piroxicam Action Pathway?,"Piroxicam (also named Feldene or Piroxicamum) is a nonsteroidal anti-inflammatory drug. Piroxicam can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of piroxicam. Piroxicam can prevent movement of leukocytes to inflammation site so that thromboxane A2 can't be produced."
What is the definition of Ibandronate Action Pathway?,"The action of ibandronate on bone tissue is based partly on its affinity for hydroxyapatite, which is part of the mineral matrix of bone. Nitrogen-containing bisphosphonates (such as pamidronate, alendronate, risedronate, ibandronate and zoledronate) appear to act as analogues of isoprenoid diphosphate lipids, thereby inhibiting farnesyl pyrophosphate (FPP) synthase, an enzyme in the mevalonate pathway of cholesterol biosynthesis. Inhibition of this enzyme in osteoclasts prevents the biosynthesis of isoprenoid lipids (FPP and GGPP) that are essential for the post-translational farnesylation and geranylgeranylation of small GTPase signaling proteins. This activity inhibits osteoclast activity and reduces bone resorption and turnover. In postmenopausal women, it reduces the elevated rate of bone turnover, leading to, on average, a net gain in bone mass."
What is the definition of Simvastatin Action Pathway?,"Simvastatin, the methylated form of lovastatin, is an inactive lactone that is metabolized in vivo to β,δ-dihydroxy acid, its most potent metabolite. Cytochrome P450 (CYP) enzymes, CYP3A4, CYP3A5, and CYP2C8, have been implicated in this activation step; CYP3A4/5 are responsible for ≥ 80% of simvastatin metabolism while CYP2C8 (not shown in pathway) contributes to ≤ 20% of its metabolism. The simvastatin hydroxy acid inhibits cholesterol synthesis via the mevalonate pathway by competitively inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. HMG-CoA reductase, a hepatic microsomal enzyme, is the enzyme responsible for the conversion of HMG-CoA to mevalonic acid, the rate-limiting step of cholesterol biosynthesis by this pathway. The active hydroxy acid is structurally similar to the reduced reaction intermediate and competes with HMG-CoA for binding to HMG-CoA reductase. Cholesterol biosynthesis accounts for approximately 80% of cholesterol in the body; thus, inhibiting this process can significantly lower cholesterol levels."
What is the definition of Acetylsalicylic Acid Action Pathway?,"Acetylsalicylic acid, also known as ASA or aspirin, belongs to a class of drugs known as non-steroidal anti-inflammatory drugs (NSAIDs). In addition to its anti-inflammatory properties, aspirin also acts as an analgesic, antipyretic and antithrombotic agent. Like most other NSAIDs, aspirin exerts its therapeutic effects by inhibiting prostaglandin G/H synthase 1 and 2, better known as cyclooxygenase-1 and -2 or simply COX-1 and -2. COX-1 and -2 catalyze the conversion of arachidonic acid to prostaglandin G2 and prostaglandin G2 to prostaglandin H2. Prostaglandin H2 is the precursor to a number of other prostaglandins, such as prostaglandin E2, involved in pain, fever and inflammation. The antipyretic properties of aspirin arise from inhibition of prostaglandin E2 synthesis in the preoptic region of the hypothalamus. Interference with adhesion and migration of granulocytes, polymorphonuclear leukocytes and macrophages at sites of inflammation account for its anti-inflammatory effects. The analgesic effects of aspirin likely occur due to peripheral action at the site of injury and possibly within the CNS.  Aspirin is unique from other NSAIDs in that it is an irreversible COX inhibitor. Aspirin irreversibly acetylates a serine side chain of COX rendering the enzyme inactive. Enzyme activity can only be regained by production of more cyclooxygenase. This unique property of aspirin and its higher selectivity for COX-1 over COX-2 makes it an effective antiplatelet agent. Platelets contain COX-1, a key enzyme in the production thromboxane A2 (TXA2), which is a potent inducer of platelet aggregation. Since platelets lack the ability to make more enzyme, TXA2 production is inhibited for the lifetime of the platelet (approximately 8 – 12 days). Aspirin is commonly used at low doses to prevent cardiovascular events such as strokes and heart attacks. At higher doses, aspirin may be used as an analgesic, anti-inflammatory and antipyretic. Aspirin may cause gastric irritation and bleeding by inhibiting the synthesis of prostaglandins that enhance and maintain the protective gastric mucous layer."
What is the definition of Etodolac Action Pathway?,"Etodolac is a non-steroidal anti-inflammatory drug (NSAID) that can be used to treat rheumatoid arthritis and osteoarthritis. Most NSAIDs are non-selective prostaglandin G/H synthase (a.k.a. cyclooxygenase or COX) inhibitors that act on both prostaglandin G/H synthase 1 and 2 (COX-1 and -2). Prostaglandin G/H synthase catalyzes the conversion of arachidonic acid to a number of prostaglandins involved in fever, pain, swelling, inflammation, and platelet aggregation. NSAIDs antagonize COX by binding to the upper portion of the active site, preventing its substrate, arachidonic acid, from entering the active site. The analgesic, antipyretic and anti-inflammatory effects of NSAIDs occur as a result of decreased prostaglandin synthesis. Etodolac was previously thought to be a non-selective COX inhibitor; however, it is now know that it is five to fifty times more selective for COX-2 than COX-1. The first part of this figure depicts the anti-inflammatory, analgesic and antipyretic pathway of etodolac.  The latter portion of this figure depicts etodolac’s potential involvement in platelet aggregation. Prostaglandin synthesis varies across different tissue types. Platelets, anuclear cells derived from fragmentation from megakaryocytes, contain COX-1, but not COX-2. COX-1 activity in platelets is required for thromboxane A2 (TxA2)-mediated platelet aggregation. Platelet activation and coagulation do not normally occur in intact blood vessels. After blood vessel injury, platelets adhere to the subendothelial collagen at the site of injury. Activation of collagen receptors initiates phospholipase C (PLC)-mediated signaling cascades resulting in the release of intracellular calcium from the dense tubula system. The increase in intracellular calcium activates kinases required for morphological change, transition to procoagulant surface, secretion of granular contents, activation of glycoproteins, and the activation of phospholipase A2 (PLA2). Activation of PLA2 results in the liberation of arachidonic acid, a precursor to prostaglandin synthesis, from membrane phospholipids. The accumulation of TxA2, ADP and thrombin mediates further platelet recruitment and signal amplification. TxA2 and ADP stimulate their respective G-protein coupled receptors, thomboxane A2 receptor and P2Y purinoreceptor 12, and inhibit the production of cAMP via adenylate cyclase inhibition. This counteracts the adenylate cyclase stimulatory effects of the platelet aggregation inhibitor, PGI2, produced by neighbouring endothelial cells. Platelet adhesion, cytoskeletal remodeling, granular secretion and signal amplification are independent processes that lead to the activation of the fibrinogen receptor. Fibrinogen receptor activation exposes fibrinogen binding sites and allows platelet cross-linking and aggregation to occur.  Neighbouring endothelial cells found in blood vessels express both COX-1 and COX-2. COX-2 in endothelial cells mediates the synthesis of PGI2, an effective platelet aggregation inhibitor and vasodilator, while COX-1 mediates vasoconstriction and stimulates platelet aggregation. PGI2 produced by endothelial cells encounters platelets in the blood stream and binds to the G-protein coupled prostacyclin receptor. This causes G-protein mediated activation of adenylate cyclase, which catalyzes the conversion of adenosine triphosphate (ATP) to cyclic AMP (cAMP). Four cAMP molecules then bind to the regulatory subunits of the inactive cAMP-dependent protein kinase holoenzyme causing dissociation of the regulatory subunits and leaving two active catalytic subunit monomers. The active subunits of cAMP-dependent protein kinase catalyze the phosphorylation of a number of proteins. Phosphorylation of inositol 1,4,5-trisphosphate receptor type 1 on the endoplasmic reticulum (ER) inhibits the release of calcium from the ER. This in turn inhibits the calcium-dependent events, including PLA2 activation, involved in platelet activation and aggregation. Inhibition of PLA2 decreases intracellular TxA2 and inhibits the platelet aggregation pathway. cAMP-dependent kinase also phosphorylates the actin-associated protein, vasodilator-stimulated phosphoprotein. Phosphorylation inhibits protein activity, which includes cytoskeleton reorganization and platelet activation. Etodolac preferentially inhibits COX-2 with little activity against COX-1. COX-2 inhibition in endothelial cells decreases the production of PGI2 and the ability of these cells to inhibit platelet aggregation and stimulate vasodilation. These effects are thought to be responsible for the adverse cardiovascular effects observed with other selective COX-2 inhibitors, such as rofecoxib, which has since been withdrawn from the market."
What is the definition of Ketoprofen Action Pathway?,"Ketoprofen (also known as (RS)-2-(3-benzoylphenyl)-propionic acid) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat rheumatoid arthritis, osteoarthritis, dysmenorrhea, and to alleviate moderate pain.. Ketoprofen can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Because of hypothalamus action, antipyretic effects may occur which will lead to vasodilation, increased peripheral blood flow and subsequent heat dissipation."
What is the definition of Ibuprofen Action Pathway?,"Ibuprofen is a non-steroidal anti-inflammatory drug (NSAID) used for its analgesic, antipyretic and anti-inflammatory properties. Like most NSAIDs, ibuprofen is a non-selective inhibitor of prostaglandin G/H synthase 1 and 2, better known as cyclooxygenase 1 and 2 or simply COX-1 and -2. COX catalyzes the conversion of arachidonic acid to a number of prostaglandins involved in fever, pain, swelling, inflammation, and platelet aggregation. Ibuprofen antagonizes COX by binding to the upper portion of the active site, preventing its substrate, arachidonic acid, from entering the active site. The analgesic, antipyretic and anti-inflammatory effects of ibuprofen occurs as a result of decreased prostaglandin synthesis. Ibuprofen is slightly more potent than aspirin and produces analgesic effects at lower doses than aspirin. Unlike aspirin, ibuprofen is a reversible COX inhibitor and thus it is not used as an antiplatelet agent. "
What is the definition of Rofecoxib Action Pathway?,"Rofecoxib, a non-steroidal anti-inflammatory drug (NSAID), is a highly selective inhibitor of cyclooxygenase-2 (COX-2), also known as prostaglandin G/H synthase 2. Like other NSAIDs, rofecoxib exerts its effects by inhibiting the synthesis of prostaglandins involved in pain, fever and inflammation. COX-2 catalyzes the conversion of arachidonic acid to prostaglandin G2 (PGG2) and PGG2 to prostaglandin H2 (PGH2). In the COX-2 catalyzed pathway, PGH2 is the precursor of prostaglandin E2 (PGE2) and I2 (PGI2). PGE2 induces pain, fever, erythema and edema. Rofecoxib antagonizes COX-2 by binding to the upper portion of the active site, preventing its substrate, arachidonic acid, from entering the active site. Similar to other COX-2 inhibitors such as celecobix and valdecoxib, rofecoxib appears to exploit slight differences in the size of the COX-1 and -2 binding pockets to gain selectivity. COX-1 contains isoleucines at positions 434 and 523, whereas COX-2 has slightly smaller valines occupying these positions. Studies support the notion that the extra methylene on the isoleucine side chains in COX-1 adds enough bulk to proclude rofecoxib from binding. Rofecoxib is 100 times more selective for COX-2 than COX-1. The analgesic, antipyretic and anti-inflammatory effects of rofecoxib occurs as a result of decreased prostaglandin synthesis.  The first part of this figure depicts the anti-inflammatory, analgesic and antipyretic pathway of rofecoxib. The latter portion of this figure depicts rofecoxib’s involvement in platelet aggregation. Prostaglandin synthesis varies across different tissue types. Platelets, anuclear cells derived from fragmentation from megakaryocytes, contain COX-1, but not COX-2. COX-1 activity in platelets is required for thromboxane A2 (TxA2)-mediated platelet aggregation. Platelet activation and coagulation do not normally occur in intact blood vessels. After blood vessel injury, platelets adhere to the subendothelial collagen at the site of injury. Activation of collagen receptors initiates phospholipase C (PLC)-mediated signaling cascades resulting in the release of intracellular calcium from the dense tubula system. The increase in intracellular calcium activates kinases required for morphological change, transition to procoagulant surface, secretion of granular contents, activation of glycoproteins, and the activation of phospholipase A2 (PLA2). Activation of PLA2 results in the liberation of arachidonic acid, a precursor to prostaglandin synthesis, from membrane phospholipids. The accumulation of TxA2, ADP and thrombin mediates further platelet recruitment and signal amplification. TxA2 and ADP stimulate their respective G-protein coupled receptors, thomboxane A2 receptor and P2Y purinoreceptor 12, and inhibit the production of cAMP via adenylate cyclase inhibition. This counteracts the adenylate cyclase stimulatory effects of the platelet aggregation inhibitor, PGI2, produced by neighbouring endothelial cells. Platelet adhesion, cytoskeletal remodeling, granular secretion and signal amplification are independent processes that lead to the activation of the fibrinogen receptor. Fibrinogen receptor activation exposes fibrinogen binding sites and allows platelet cross-linking and aggregation to occur. Neighbouring endothelial cells found in blood vessels express both COX-1 and COX-2. COX-2 in endothelial cells mediates the synthesis of PGI2, an effective platelet aggregation inhibitor and vasodilator, while COX-1 mediates vasoconstriction and stimulates platelet aggregation. PGI2 produced by endothelial cells encounters platelets in the blood stream and binds to the G-protein coupled prostacyclin receptor. This causes G-protein mediated activation of adenylate cyclase, which catalyzes the conversion of adenosine triphosphate (ATP) to cyclic AMP (cAMP). Four cAMP molecules then bind to the regulatory subunits of the inactive cAMP-dependent protein kinase holoenzyme causing dissociation of the regulatory subunits and leaving two active catalytic subunit monomers. The active subunits of cAMP-dependent protein kinase catalyze the phosphorylation of a number of proteins. Phosphorylation of inositol 1,4,5-trisphosphate receptor type 1 on the endoplasmic reticulum (ER) inhibits the release of calcium from the ER. This in turn inhibits the calcium-dependent events, including PLA2 activation, involved in platelet activation and aggregation. Inhibition of PLA2 decreases intracellular TxA2 and inhibits the platelet aggregation pathway. cAMP-dependent kinase also phosphorylates the actin-associated protein, vasodilator-stimulated phosphoprotein. Phosphorylation inhibits protein activity, which includes cytoskeleton reorganization and platelet activation. Rofecoxib preferentially inhibits COX-2 with little activity against COX-1. COX-2 inhibition in endothelial cells decreases the production of PGI2 and the ability of these cells to inhibit platelet aggregation and stimulate vasodilation. These effects are thought to be responsible for the rare, but severe, adverse cardiovascular effects observed with rofecoxib, which has since been withdrawn from the market. "
What is the definition of Pravastatin Action Pathway?,"Pravastatin inhibits cholesterol synthesis via the mevalonate pathway by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. HMG-CoA reductase is the enzyme responsible for the conversion of HMG-CoA to mevalonic acid, the rate-limiting step of cholesterol synthesis by this pathway. Pravastatin bears a chemical resemblance to the reduced HMG-CoA reaction intermediate that is formed during catalysis. Structure-activity relationship studies have demonsotrated that statins bind to HMG-CoA reductase at the same site as the reduced reaction intermediate and are held in place by similar chemical interactions. Cholesterol biosynthesis accounts for approximately 80% of cholesterol in the body; thus, inhibiting this process can significantly lower cholesterol levels. Pravstatin was derived from the microbial transformation of mevastatin, which is a natural compound produced by Penicillium citinium and the first statin ever studied. Unlike lovastatin and simvastatin, pravastatin is relatively hydrophilic and does not require hydrolysis for activation. Increased hydrophilicity accounts for its decreased penetration of lipophilic peripheral cells, increased selectivity for hepatic tissues and decreased side effects relative to simvastatin and lovastatin. "
What is the definition of Rosuvastatin Action Pathway?,"Rosuvastatin inhibits cholesterol synthesis via the mevalonate pathway by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. HMG-CoA reductase is the enzyme responsible for the conversion of HMG-CoA to mevalonic acid, the rate-limiting step of cholesterol synthesis by this pathway. The active form of statins bears a chemical resemblance to the reduced HMG-CoA reaction intermediate that is formed during catalysis. Structure-activity relationship studies have demonstrated that statins bind to HMG-CoA reductase at the same site as the reduced intermediate and are held in place by similar chemical interactions. Unlike Lovastatin and simvastatin, which undergo in vivo hydrolysis to their active form rosuvastatin is synthetically produced in active form. Cholesterol biosynthesis accounts for approximately 80% of cholesterol in the body; thus, inhibiting this process can significantly lower cholesterol levels. "
What is the definition of Diclofenac Action Pathway?,"Diclofenac (also named Voltaren) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat prostaglandin G/H synthase related fever, swelling, pain and inflammation. Diclofenac can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis is caused by presence of diclofenac."
What is the definition of Sulindac Action Pathway?,"Sulindac is a non-steroidal anti-inflammatory drug (NSAID). Like most NSAIDs, sulindac is a non-selective prostaglandin G/H synthase (a.k.a. cyclooxygenase or COX) inhibitor that acts on both prostaglandin G/H synthase 1 and 2 (COX-1 and -2). COX catalyzes the conversion of arachidonic acid to prostaglandin G2 and prostaglandin G2 to prostaglandin H2. Prostaglandin H2 is the precursor of a number of prostaglandins involved in fever, pain, swelling and inflammation. The analgesic, antipyretic and anti-inflammatory effects of sulindac occurs as a result of decreased prostaglandin synthesis.  "
What is the definition of Alendronate Action Pathway?,"Alendronate (also known as alendronic acid) is a type of bisphosphonate medication with nitrogen that can inhibit FPP synthase, which can block the pathway that produce geranyl-PP and farnesyl pyrophosphate. Geranyl-PP and farnesyl pyrophosphate are the compounds that are required for small GTPase signalling proteins undergo post-translational farnesylation and geranylgeranylation. Therefore, lack the formation of geranyl-PP and farnesyl pyrophosphate can prevent osteoclast activity, which lead to prevention of reduced bone resorption and turnover. "
What is the definition of Celecoxib Action Pathway?,"Celecoxib, a non-steroidal anti-inflammatory drug (NSAID), is a selective inhibitor of cyclooxygenase-2 (COX-2), also known as prostaglandin G/H synthase 2. Like other NSAIDs, celecoxib exerts its effects by inhibiting the synthesis of prostaglandins involved in pain, fever and inflammation. COX-2 catalyzes the conversion of arachidonic acid to prostaglandin G2 (PGE2) and PGE2 to prostaglandin H2 (PGH2). In the COX-2 catalyzed pathway, PGH2 is the precusor of prostaglandin E2 (PGE2) and I2 (PGI2). PGE2 induces pain, fever, erythema and edema. Celecoxib antagonizes COX-2 by binding to the upper portion of the active site, preventing its substrate, arachidonic acid, from entering the active site. Similar to other COX-2 inhibitors, such as rofecoxib and valdecoxib, celecoxib appears to exploit slight differences in the size of the COX-1 and -2 binding pockets to gain selectivity. COX-1 contains isoleucines at positions 434 and 523, whereas COX-2 has slightly smaller valines occupying these positions. Studies support the notion that the extra methylene on the isoleucine side chains in COX-1 adds enough bulk to proclude celecoxib from binding. Celecoxib is approximately ten times more selective for COX-2 than COX-1. Celecoxib is used mainly to treat rheumatoid arthritis and osteoarthritis which require something more potent than aspirin. The analgesic, antipyretic and anti-inflammatory effects of celecoxib occur as a result of decreased prostaglandin synthesis.  The first part of this figure depicts the anti-inflammatory, analgesic and antipyretic pathway of celecoxib. The latter portion of this figure depicts celecoxib’s potential involvement in platelet aggregation. Prostaglandin synthesis varies across different tissue types. Platelets, which are anuclear cells derived from fragmentation of megakaryocytes, contain COX-1, but not COX-2. COX-1 activity in platelets is required for thromboxane A2 (TxA2)-mediated platelet aggregation. Platelet activation and coagulation do not normally occur in intact blood vessels. After blood vessel injury, platelets adhere to the subendothelial collagen at the site of injury. Activation of collagen receptors initiates phospholipase C (PLC)-mediated signaling cascades resulting in the release of intracellular calcium from the dense tubula system. The increase in intracellular calcium activates kinases required for morphological change, transition to the procoagulant surface, secretion of granular contents, activation of glycoproteins, and the activation of phospholipase A2 (PLA2). Activation of PLA2 results in the liberation of arachidonic acid, a precursor to prostaglandin synthesis, from membrane phospholipids. The accumulation of TxA2, ADP and thrombin mediates further platelet recruitment and signal amplification. TxA2 and ADP stimulate their respective G-protein coupled receptors, thomboxane A2 receptor and P2Y purinoreceptor 12, and inhibit the production of cAMP via adenylate cyclase inhibition. This counteracts the adenylate cyclase stimulatory effects of the platelet aggregation inhibitor, PGI2, produced by neighbouring endothelial cells. Platelet adhesion, cytoskeletal remodeling, granular secretion and signal amplification are independent processes that lead to the activation of the fibrinogen receptor. Fibrinogen receptor activation exposes fibrinogen binding sites and allows platelet cross-linking and aggregation to occur. Neighbouring endothelial cells found in blood vessels express both COX-1 and COX-2. COX-2 in endothelial cells mediates the synthesis of PGI2, an effective platelet aggregation inhibitor and vasodilator, while COX-1 mediates vasoconstriction and stimulates platelet aggregation. PGI2 produced by endothelial cells encounters platelets in the blood stream and binds to the G-protein coupled prostacyclin receptor. This causes G-protein mediated activation of adenylate cyclase, which catalyzes the conversion of adenosine triphosphate (ATP) to cyclic AMP (cAMP). Four cAMP molecules then bind to the regulatory subunits of the inactive cAMP-dependent protein kinase holoenzyme causing dissociation of the regulatory subunits and leaving two active catalytic subunit monomers. The active subunits of cAMP-dependent protein kinase catalyze the phosphorylation of a number of proteins. Phosphorylation of inositol 1,4,5-trisphosphate receptor type 1 on the endoplasmic reticulum (ER) inhibits the release of calcium from the ER. This in turn inhibits the calcium-dependent events, including PLA2 activation, involved in platelet activation and aggregation. Inhibition of PLA2 decreases intracellular TxA2 and inhibits the platelet aggregation pathway. cAMP-dependent kinase also phosphorylates the actin-associated protein, vasodilator-stimulated phosphoprotein. Phosphorylation inhibits protein activity, which includes cytoskeleton reorganization and platelet activation. Celecoxib preferentially inhibits COX-2 with little activity against COX-1. COX-2 inhibition in endothelial cells decreases the production of PGI2 and the ability of these cells to inhibit platelet aggregation and stimulate vasodilation. These effects are thought to be responsible for the adverse cardiovascular effects observed with other selective COX-2 inhibitors, such as rofecoxib, which has since been withdrawn from the market. "
What is the definition of Ketorolac Action Pathway?,"Ketorolac (also named Toradol) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to relieve pain (analgesic), reduce fever (antipyretic) and swelling. Ketorolac can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Since prostaglandin is the messenger molecules in the process of inflammation; hence, inhibition of prostaglandin synthesis can reduce the pain, fever and inflammation."
What is the definition of Pterine Biosynthesis?,"Folates are essential cofactors that provide one-carbon moieties in various states of reduction for biosynthetic reactions. The processes shown in this pathway include transport reactions by which folates are taken up by cells and moved intracellularly, folate conjugation with glutamate (required for folate retention within a cell), as well as the synthesis of pterines, which are used in folate synthesis. Two branches are depicted: Pterin synthesis and Folate biosynthesis. In pterin synthesis, GTP is the precursor for pterin biosynthesis. The enzyme GTP-cyclohydrolase I produces dihydroneopterin triphosphate from GTP as the first step. The product is then dephosphorylated to dihydroneopterin and yields, after removal of a C2-residue from the C3-side chain 6- hydroxymethyldihydropterin, which is the precursor for folate biosynthesis. In terms of folate biosynthesis, the basic steps are: folate → dihydrofolate → tetrahydrofolate ↔ methylene-THF → methyl-THF. More specifically, the pathway leading to the formation of tetrahydrofolate (FH4) begins when folate (F) is reduced to dihydrofolate (DHF) (FH2), which is then reduced to THF. Dihydrofolate reductase catalyses the last step. Vitamin B3 in the form of NADPH is a necessary cofactor for both steps of the synthesis. Methylene-THF (CH2FH4) is formed from THF by the addition of methylene groups from one of three carbon donors: formaldehyde, serine, or glycine. Methyl tetrahydrofolate (CH3-THF) can be made from methylene-THF by reduction of the methylene group with NADPH. Another form of THF, formyl-THF (or folinic acid) results from oxidation of methylene-THF or is formed from formate donating formyl group to THF. Finally, histidine can donate a single carbon to THF to form methenyl-THF."
What is the definition of Steroidogenesis?,"Steroidogenesis is a process that through the transformations of other steroids, produces a desired steroid. Some of these desired steroids include cortisol, corticoids, testosterone, estrogens, aldosterone and progesterone. To begin the synthesis of steroid hormones, cholesterol synthesizes a hormone called pregnenolone. This is done by cholesterol from the cytosol or lysosome being brought to the mitochondria and becoming fixed in the inner mitochondrial membrane. Once there, the cholesterol becomes pregnenolone through three reactions. The enzyme responsible for catalyzing all three reactions is CYP11A, a side chain cleavage enzyme. After being created, the pregnenolone enters the cytosol, where the cholesterol originated. Once in the cytosol, pregenolone synthesizes progesterone, using two reactions. These two reactions are both catalyzed by an enzyme called 3-beta-hydroxysteroid dehydrogenase/isomerase. The enzyme CYP21A2 then hydroxylates progesterone, which converts it to deoxycorticosterone. Deoxycorticosterone then undergoes three reactions catalyzed by CYP11B2 to become aldosterone. 17alpha-hydroxyprogesterone is created from pregnenolone by using 3-beta-hydroxysteroid dehydrogenase/isomerase. CYP21A2 then hydroxylates 17alpha-hydroxyprogesterone which results in the production of 11-deoxycortisol. CYP11B1 quickly converts 11-deoxycortisol to cortisol. Cortisol is an active steroid hormone, and its conversion to the inactive cortisone has been known to occur in various tissues, with increased conversion occurring in the liver. Pregnenolone is an important hormone as it is responsible for the beginning of the synthesis of many hormones not pictured in this pathway such as testosterone and estrogen. Cortisol receptors are found in almost every bodily cell, so this hormone affects a wide range of body functions. Some of these functions include metabolism regulation, inflammation reduction, regulating blood sugar levels and blood pressure, and helps with the formation of memories. "
What is the definition of Tyrosine Metabolism?,"The tyrosine metabolism pathway describes the many ways in which tyrosine is catabolized or transformed to generate a wide variety of biologically important molecules. In particular, tyrosine can be metabolized to produce hormones such as thyroxine and triiodothyronine or it can be metabolized to produce neurotransmitters such as L-DOPA, dopamine, adrenaline, or noradrenaline. Tyrosine can also serve as a precursor of the pigment melanin and for the formation of Coenzyme Q10. Additionally, tyrosine can be catabolized all the way down into fumarate and acetoacetate. This particular pathway for tyrosine degradation starts with an alpha-ketoglutarate-dependent transamination reaction of tyrosine, which is mediated through the enzyme known as tyrosine transaminase. This process generates p-hydroxyphenylpyruvate. This aromatic acid is then acted upon by p-hydroxylphenylpyruvate-dioxygenase which generates the compound known as homogentisic acid or homogentisate (2,5-dihydroxyphenyl-1-acetate). In order to split the aromatic ring of homogentisate, a unique dioxygenase enzyme known as homogentisic acid 1,2-dioxygenase is required. Through this enzyme, maleylacetoacetate is created from the homogentisic acid precursor.  The accumulation of excess homogentisic acid and its oxide (named alkapton) in the urine of afflicted individuals can lead to a condition known as alkaptonuria.  This genetic condition, also known as an inborn error of metabolism or IEM, occurs if there are mutations in the homogentisic acid 1,2-dioxygenase gene. After the breakdown of homogentisate is achieved, maleylacetoacetate is then attacked by the enzyme known as maleylacetoacetate-cis-trans-isomerase, which generates fumarylacetate. This isomerase catalyzes the rotation of the carboxyl group created from the hydroxyl group via oxidation. This cis-trans-isomerase uses glutathione as a coenzyme or cofactor. The resulting product, fumarylacetoacetate, is then split into acetoactate and fumarate via the enzyme known as fumarylacetoacetate-hydrolase through the addition of a water molecule. Through this set of reactions fumarate and acetoacetate (3-ketobutyroate) are liberated. Acetoacetate is a ketone body, which is activated with succinyl-CoA, and thereafter it can be converted into acetyl-CoA, which in turn can be oxidized by the citric acid cycle (also known as the TCA cycle) or used for fatty acid synthesis. Other aspects of tyrosine metabolism include the generation of catecholamines. In this process, the enzyme known as tyrosine hydroxylase (or AAAH or TYH) catalyzes the conversion of tyrosine to L-DOPA. The L-DOPA can then be converted via the enzyme DOPA decarboxylase (DDC) to dopamine. Dopamine can then be converted to 3-methoxytyramine via the action of catechol-O-methyltransferase (COMT). Dopamine can also be converted to norepinephrine (noradrenaline) through the action of the enzyme known as dopamine beta hydroxylase (DBH).  Norepinephrine can then be converted to epinephrine (adrenaline) through the action of phenyethanolamine N-methyltransferase (PNMT). Catecholamines such as L-DOPA, dopamine and methoxytyramine are produced mainly by the chromaffin cells of the adrenal medulla and by neuronal cells found in the brain. For example, dopamine, which acts as a neurotransmitter, is mostly produced in neuronal cell bodies in the ventral tegmental area and the substantia nigra while epinephrine is produced in neurons in the human brain that express PMNT. Catecholamines typically have a half-life of a few minutes in the blood. They are typically degraded via catechol-O-methyltransferases (COMT) or by deamination via monoamine oxidases (MAO). Another important aspect of tyrosine metabolism includes the production of melanin. Melanin is produced through a mechanism known as melanogenesis, a process that involves the oxidation of tyrosine followed by the polymerization of these oxidation by-products. Melanin pigments are produced in a specialized group of cells known as melanocytes. There are three types of melanin: pheomelanin, eumelanin, and neuromelanin of which eumelanin is the most common. Melanogenesis, especially in the skin, is initiated through the exposure to UV light. Melanin is the primary pigment that determines skin color. Melanin is also found in hair and the pigmented tissue underlying the iris. The first step in the synthesis for both eumelanins and pheomelanins is the conversion of tyrosine to dopaquinone by the enzyme known as tyrosinase. The resulting dopaquinone can combine with cysteine to produce cysteinyldopa, which then polymerizes to form pheomelanin. Dopaquinone can also form lecuodopachrome, which then can be converted to dopachrome (a cyclization product) and this eventually becomes eumelanin. Tyrosine plays a critical role in the synthesis of thyroid hormones. Thyroid hormones are produced and released by the thyroid gland and include triiodothyronine (T3) and thyroxine (T4). These two hormones are responsible for regulating metabolism. Thyroxine was discovered and isolated by Edward Calvin Kendall in 1915. Thyroid hormones are produced by the follicular cells of the thyroid gland through the action of thyroperoxidase, which iodinates reactive tyrosine residues on thyroglobulin.  Proteolysis of the thyroglobulin in cellular lysosomes releases the small molecule thyroid hormones. In mammals, tyrosine can be formed from dietary phenylalanine by the enzyme phenylalanine hydroxylase, found in large amounts in the liver. Phenylalanine is considered an essential amino acid, while tyrosine (which can be endogenously synthesized) is not.  In plants and most microbes, tyrosine is produced via prephenate, an intermediate that is produced as part of the shikimate pathway."
What is the definition of Inositol Metabolism?,"Inositol (also known as myo-inositol) is a carbocyclic polyol that plays an important role as the structural basis for a number of secondary messengers in eukaryotic cells, including inositol phosphates, phosphatidylinositol (PI) and phosphatidylinositol phosphate (PIP) lipids. It is found in many foods, in particular, in cereals with high bran content, nuts, beans, and fruit, especially cantaloupe melons and oranges. Inositol is not considered a vitamin itself because it can be synthesised by the body. Myo-Inositol is synthesized from glucose-6-phosphate (G-6-P) in two steps. First, G-6-P is isomerised by inositol-3-phosphate synthase (ASYNA1) to myo-inositol 3-phosphate, which is then dephosphorylated by inositol monophosphatase (IMPase 1) to give free myo-inositol. The synthesis of phosphatidylinositol is catalyzed by phosphatidylinositol synthase and involves CDP-diacylglycerol and myo-inositol. Phosphatidylinositol phosphate lipids are a product of class I, II and III phosphoinositide 3-kinases (PI 3-kinases) acting on phosphatidylinositol. Many inositol phosphates are made by the hydrolysis of phosphatidylinositol phosphates by phospholipase C. They may also be synthesized or remodeled via various kinases and phosphatases."
What is the definition of Glycerolipid Metabolism?,"The glycerolipid metabolism pathway describes the synthesis of glycerolipids such as monoacylglycerols (MAGs), diacylglycerols (DAGs), triacylglycerols (TAGs), phosphatidic acids (PAs), and lysophosphatidic acids (LPAs). The process begins with cytoplasmic 3-phosphoglyceric acid (a product of glycolysis). This molecule is dephosphorylated via the enzyme glycerate kinase to produce glyceric acid. Glyceric acid is then transformed to glycerol (via the action of aldehyde dehydrogenase and aldose reductase). The free, cytoplasmic glycerol can then be phosphorylated to glycerol-3-phosphate through the action of glycerol kinase.  Glycerol-3-phosphate can then enter the endoplasmic reticulum where glycerol-3-phosphate acyltransferase (GPAT) may combine various acyl-CoA moieties (which donate acyl groups) to form lysophosphatidic (LPA) or phosphatidic acid (PA).  The resulting phosphatidic acids can be dephosphorylated via lipid phosphate phosphohydrolase (also known as phosphatidate phosphatase) to produce diacylglycerols (DAGs). The resulting DAGs can be converted into triacylglycerols (TAGs) via the addition of another acyl group (contributed via acyl-CoA) and the action of 1-acyl-sn-glycerol-3-phosphate acyltransferase. Extracellularly, the triacylglycerols (TAGs) can be converted to monoacylglycerols (MAGs) through the action of hepatic triacylglycerol lipase. In addition to this cytoplasmic route of glycerolipid synthesis, another route via mitochondrial synthesis also exists.  This route begins with glycerol-3-phosphate, which can be either derived from dihydroxyacetone phosphate (DHAP), a product of glycolysis (usually in the cytoplasm of liver or adipose tissue cells) or from glycerol itself. Glycerol-3-phosphate in the mitochondria is first acylated via acyl-coenzyme A (acyl-CoA) through the action of mitochondrial glycerol-3-phosphate acyltransferase to form lysophosphatidic acid (LPA). Once synthesized, lysophosphatidic acid is then acylated with another molecule of acyl-CoA via the action of 1-acyl-sn-glycerol-3-phosphate acetyltransferase to yield phosphatidic acid. Phosphatidic acid is then dephosphorylated to form diacylglycerol. Specifically, diacylglycerol is formed by the action of phosphatidate phosphatase (also known as lipid phosphate phosphohydrolase) on phosphatidic acid coupled with the release of a phosphate. The phosphatase exists as 3 isozymes. Diacylglycerol is a precursor to triacylglycerol (triglyceride), which is formed in the addition of a third fatty acid to the diacylglycerol by the action of diglyceride acyltransferase. Since diacylglycerol is synthesized via phosphatidic acid, it will usually contain a saturated fatty acid at the C-1 position on the glycerol moiety and an unsaturated fatty acid at the C-2 position. When the body uses stored fat as a source of energy, glycerol and fatty acids are released into the bloodstream. Fatty acids, stored as triglycerides in humans, are an important and a particularly rich source of energy. The energy yield from a gram of fatty acids is approximately 9 kcal/g (39 kJ/g), compared to 4 kcal/g (17 kJ/g) for carbohydrates. Since the hydrocarbon portion of fatty acids is hydrophobic, these molecules can be stored in a relatively anhydrous (water-free) environment. Fatty acids can hold more than six times the amount of energy than sugars on a weight basis. In other words, if you relied on sugars or carbohydrates to store energy, then you would need to carry 67.5 lb (31 kg) of glycogen to have the energy equivalent to 10 lb (5 kg) of fat."
What is the definition of Bile Acid Biosynthesis?,"Bile acids are made in the liver by the cytochrome P450-mediated oxidation of cholesterol.  They are conjugated with taurine or the amino acid glycine, or with a sulfate or a glucuronide, and are then stored in the gallbladder.  Upon eating a meal, the contents of the gallbladder are secreted into the intestine, where bile acids serve the purpose of emulsifying dietary fats.  Bile acids serve other functions, including eliminating cholesterol from the body, driving the flow of bile to eliminate catabolites from the liver, emulsifying lipids and fat soluble vitamins in the intestine, and aiding in the reduction of the bacteria flora found in the small intestine and biliary tract.  Bile acids formed by synthesis in the liver are termed ""primary"" bile acids, and those made by bacteria are termed ""secondary"" bile acids.  In the liver, synthesis of bile acids and bile salts is initiated with the conversion of cholesterol esters (from circulating lipoprotein particles) to cholesterol, then to 7alpha-hydroxycholesterol then to 4-cholesten-7alpha-ol-3-one.  The pathway then branches: hydroxylation of 4-cholesten-7alpha-ol-3-one to 4-cholesten-7alpha, 12alpha-diol-3-one leads ultimately to the formation of cholate, while its reduction to 5beta-cholestan-7alpha-ol-3-one leads to the formation of chenodeoxycholate.  Chenodeoxycholate has two hydroxyl groups at positions 3-alpha and 7-alpha and is a key bile acid.  Its chief drawback lies in the ability of intestinal bacteria to remove the 7-alpha hydroxyl group via dehydroxylation.  The resulting bile acid has only a 3-alpha hydroxyl group and is termed lithocholic acid.  To avoid the problems associated with the production of lithocholic acid, most mammals add a third hydroxyl group at the 12 position to chenodeoxycholic acid to create cholic acid.  In this manner, the subsequent removal of the 7-alpha hydroxyl group by intestinal bacteria will result in a less toxic, still functional dihydroxy bile acid.  In the intestine, cholic acid is dehydroxylated to form the dihydroxy bile acid deoxycholic acid.  Prior to secretion by the liver, they are conjugated with either the amino acid glycine or taurine through conversion to a Coenzyme A derivative and subsequent conjugation.  In the body, glycocholate, taurocholate, glycochenodeoxycholate, and taurochenodeoxycholate are released from hepatocytes into the bile and ultimately into the lumen of the small intestine, where they function as detergents to solubilize dietary fats.  Conjugation increases water solubility, preventing passive re-absorption once secreted into the small intestine.  As a result, the concentration of bile acids in the small intestine can stay high enough to form micelles and solubilize lipids.  Bile acids, in particular chenodeoxycholic acid (CDCA) and cholic acid (CA), can regulate the expression of genes involved in their synthesis, thereby, creating a feed-back loop.  The elucidation of this regulatory pathway came about as a consequence of the isolation of a class of receptors called the farnesoid X receptors, FXRs.  The FXRs belong to the superfamily of nuclear receptors that includes the steroid/thyroid hormone receptor family as well as the liver X receptors (LXRs), retinoid X receptors (RXRs), and the peroxisome proliferator-activated receptors (PPARs).  The FXR genes are expressed at highest levels in the intestine and liver. "
What is the definition of Glycolysis?,"Glycolysis is a metabolic pathway with sequence of ten reactions involving ten intermediate compounds that converts glucose to pyruvate. Glycolysis release free energy for forming high energy compound such as ATP and NADH. Glycolysis is consisted of two phases, which one of them is chemical priming phase and second phase is energy-yielding phase. As the starting compound of chemical priming phase, D-glucose can be obtained from galactose metabolism or imported by monosaccharide-sensing protein 1 from outside of cell. D-Glucose is catalyzed by probable hexokinase-like 2 protein to form glucose 6-phosphate which is powered by ATP.  Glucose 6-phosphate transformed to fructose 6-phosphate by glucose-6-phosphate isomerase, which the later compound will be converted to fructose 1,6-bisphosphate, which is the last reaction of chemical priming phase  by 6-phosphofructokinase with cofactor magnesium, and it is also powered by ATP. Before entering the second phase, aldolase catalyzing the hydrolysis of F1,6BP into dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. Dihydroxyacetone phosphate and glyceraldehyde 3-phosphate can convert to each other bidirectionally by facilitation of triosephosphate isomerase. The second phase of glycolysis is yielding-energy phase that produce ATP and NADH. At the first step, D-glyceraldehyde 3-phosphate is catalyzed to glyceric acid 1,3-biphosphate by glyceraldehyde-3-phosphate dehydrogenase with NAD, which also generate NADH. ATP is generated through the reaction that convert glyceric acid 1,3-biphosphate to 3-phosphoglyceric acid. Phosphoglycerate mutase 2 catalyze 3-phosphoglyceric acid to 2-Phospho-D-glyceric acid,  and alpha-enolase with cofactor magnesium catalyzes 2-Phospho-D-glyceric acid to phosphoenolpyruvic acid. Eventually, plastidial pyruvate kinase 4 converts phosphoenolpyruvic acid to pyruvate with cofactor magnesium and potassium and ADP. Pyruvate will undergo pyruvate metabolism, tyrosine metabolism and pantothenate and CoA biosynthesis. "
What is the definition of Sphingolipid Metabolism?,"The sphingolipid metabolism pathway depicted here describes the synthesis of sphingolipids which include sphingomyelins, ceramides, phosphoceramides, glucosylceramides, galactosylceramides, sulfagalactosylceramides, lactosylceramides, and various other ceramides. The core of a sphingolipid is the long-chain amino alcohol called sphingosine. Amino acylation, with a long-chain fatty acid, at the 2-carbon position of sphingosine yields a ceramide. Sphingolipids are a component of all membranes but are particularly abundant in the myelin sheath. De novo sphingolipid synthesis begins at the cytoplasmic side of the ER (endoplasmic reticulum) with the formation of 3-keto-dihydrosphingosine (also known as 3-ketosphinganine) by the enzyme known as serine palmitoyltransferase (SPT). The preferred substrates for this reaction are palmitoyl-CoA and serine. Next, 3-keto-dihydrosphingosine is reduced to form dihydrosphingosine (also known as sphinganine) via the enzyme 3-ketodihydrosphingosine reductase (KDHR), which is also known as 3-ketosphinganine reductase. Dihydrosphingosine (sphinganine) is acylated by the action of several dihydroceramide synthases (CerS) to form dihydroceramide. Dihydroceramide is then desaturated in the original palmitic portion of the lipid via dihydroceramide desaturase 1 (DES1) to form ceramide. Following the conversion to ceramide, sphingosine is released via the action of ceramidase. Sphingosine can be re-converted into a ceramide by condensation with an acyl-CoA catalyzed by the various CerS enzymes. Ceramide may be phosphorylated by ceramide kinase to form ceramide-1-phosphate. Alternatively, it may be glycosylated by glucosylceramide synthase (to form a glucosylceramide) or galactosylceramide synthase (to form a galactosylceramide). Additionally, it can be converted to sphingomyelin by the addition of a phosphorylcholine headgroup by sphingomyelin synthase (SMS). Sphingomyelins are the only sphingolipids that are phospholipids. Diacylglycerol is also generated via this process. Alternately, ceramide may be broken down by a ceramidase to form sphingosine. Sphingosine may be phosphorylated to form sphingosine-1-phosphate, which may, in turn, be dephosphorylated to regenerate sphingosine. Sphingolipid catabolism allows the reversion of these metabolites to ceramide. The complex glycosphingolipids are hydrolyzed to glucosylceramide and galactosylceramide. These lipids are then hydrolyzed by beta-glucosidases and beta-galactosidases to regenerate ceramide. Similarly, sphingomyelins may be broken down by sphingomyelinase to create ceramides and phosphocholine. The only route by which sphingolipids are converted into non-sphingolipids is through sphingosine-1-phosphate lyase. This forms ethanolamine phosphate and hexadecenal."
What is the definition of Propanoate Metabolism?,"This pathway depicts the metabolism of propionic acid. Propionic acid in mammals typically arises from the production of the acid by gut or skin microflora. Propionic acid producing bacteria (Propionibacterium sp.) are particularly common in sweat glands of mammals.  After entering a cell, the propionic acid (propanoate) then enters the mitochondria where it is converted into propanol adenylate (or propionyl adenylate or propionyl-AMP) via propionyl-CoA synthetase and acetyl-CoA synthetase. The propionyl adenylate then is converted into propionyl coenzyme A (propionyl-CoA) via the same pair of enzymes. Propionyl-CoA is a relatively common compound that can also arise from the metabolic breakdown of fatty acids containing odd numbers of carbon atoms. Propionyl-CoA is also known to arise from the breakdown of some amino acids. Since propanoate has three carbons, propionyl-CoA cannot directly enter the beta-oxidation cycle (which requires two carbons from acetyl-CoA). Therefore, in most vertebrates, propionyl-CoA is carboxylated into D-methylmalonyl-CoA via propionyl-CoA carboxylase. The resulting compound is isomerized into L-methylmalonyl-CoA via methylmalonyl-CoA epimerase.  A vitamin B12-dependent enzyme, called methylmalonyl CoA mutase catalyzes the rearrangement of L-methylmalonyl-CoA to succinyl-CoA, which is an intermediate of the citric acid cycle. Also depicted in this pathway is another propionic acid homolog called hydroxypropanoic acid (hydroxypropionate). This compound is also produced by bacteria and imported into cells. Hydroxypropionate can be converted into 3-hydroxypropionyl-CoA. This compound can be either enzymatically converted to acryloyl-CoA and then to propionyl-CoA or it can spontaneously convert to malonyl-CoA. Malonyl-CoA can convert into acetyl-CoA (via acetyl-CoA carboxylase in the cytoplasm or malonyl carboxylase in the mitochondria) whereupon it may enter a variety of pathways. In a rare genetic metabolic disorder called propionic acidemia, propionate acts as a metabolic toxin in liver cells by accumulating in the liver mitochondria as propionyl-CoA and its derivative methylcitrate. Both propionyl-CoA and methylcitrate are known TCA inhibitors. Glial cells are particularly susceptible to propionyl-CoA accumulation. In fact, when propionate is infused into rat brains and take up by the glial cells, it leads to behavioural changes that resemble autism (PMID: 16950524)."
What is the definition of Starch and Sucrose Metabolism?," The digestion of starch begins with the action of amylase enzymes secreted in the saliva and small intestine, which convert it to maltotriose, maltose, limit dextrins, and some glucose.  Digestion of the limit dextrins and disaccharides, both dietary and starch-derived, to monosaccharides – glucose, galactose, and fructose – is accomplished by enzymes located on the luminal surfaces of enterocytes lining the microvilli of the small intestine.  Once released from starch or once ingested, sucrose can be degraded into beta-D-fructose and alpha-D-glucose via lysosomal alpha-glucosidase or sucrose-isomaltase.  Beta-D-fructose can be converted to beta-D-fructose-6-phosphate by glucokinase and then to alpha-D-glucose-6-phosphate by the action of glucose phosphate isomerase.  Phosphoglucomutase 1 can then act on alpha-D-glucose-6-phosphate (G6P) to generate alpha-D-glucose-1-phosphate.  Alpha-D-glucose-1-phosphate (G6P) has several possible fates.  It can enter into gluconeogenesis, glycolysis or the nucleotide sugar metabolism pathway.  UDP-glucose pyrophosphorylase 2 can convert alpha-D-glucose-1-phosphate into UDP-glucose, which can then be converted to UDP-xylose or UDP-glucuronate and, eventually to glucuronate.  UDP-glucose can also serve as a precursor to the synthesis of glycogen via glycogen synthase.  More specifically, glycogen is synthesized from monomers of UDP-glucose by the enzyme glycogen synthase, which progressively lengthens the glycogen chain with (α1→4) bonded glucose.  As glycogen synthase can only lengthen an existing chain, the protein glycogenin is needed to initiate the synthesis of glycogen.  The glycogen-branching enzyme, amylo (α1→4) to (α1→6) transglycosylase, catalyzes the transfer of a terminal fragment of 6-7 glucose residues from a nonreducing end to the C-6 hydroxyl group of a glucose residue deeper into the interior of the glycogen molecule.  The branching enzyme can only act upon a branch having at least 11 residues, and the enzyme may transfer to the same glucose chain or adjacent glucose chains.  Another enzyme known as starch phosphorylase or glycogen phosphorylase can also convert starch into glycogen.  Glycogen functions as the secondary short term energy storage in animal cells.  It is made primarily by the liver and the muscles, but can also be made by glycogenesis within the brain and stomach.  Glycogen is the analogue of starch, a less branched glucose polymer in plants, and is commonly referred to as animal starch, having a similar structure to amylopectin.  Glycogen is found in the form of granules in the cytosol in many cell types, and plays an important role in the glucose cycle.  Glycogen is cleaved from the nonreducing ends of the chain by the enzyme glycogen phosphorylase to produce monomers of glucose-1-phosphate that is then converted to glucose 6-phosphate (G6P).  G6P can continue on the glycolysis pathway and be used as fuel or G6P can enter the pentose phosphate pathway via the enzyme glucose-6-phosphate dehydrogenase to produce NADPH and 5-carbon sugars or, in the liver and kidney, G6P can be dephosphorylated back to glucose by the enzyme glucose 6-phosphatase.  This is the final step in the gluconeogenesis pathway. "
What is the definition of Nicotinate and Nicotinamide Metabolism?,"Nicotinate (niacin) and nicotinamide - more commonly known as vitamin B3 - are precursors of the coenzymes nicotinamide-adenine dinucleotide (NAD+) and nicotinamide-adenine dinucleotide phosphate (NADP+). NAD+ synthesis occurs either de novo from amino acids, or a salvage pathway from nicotinamide. Most organisms use the de novo pathway whereas the savage pathway is only typically found in mammals. The specifics of the de novo pathway varies between organisms, but most begin by forming quinolinic acid (QA) from tryptophan (Trp) in animals, or aspartic acid in some bacteria (intestinal microflora) and plants.Nicotinate-nucleotide pyrophosphorylase converts QA into nicotinic acid mononucleotide (NaMN) by transfering a phosphoribose group. Nicotinamide mononucleotide adenylyltransferase then transfers an adenylate group to form nicotinic acid adenine dinucleotide (NaAD). Lastly, the nicotinic acid group is amidated to form a nicotinamide group, resulting in a molecule of nicotinamide adenine dinucleotide (NAD). Additionally, NAD can be phosphorylated to form NADP. The salvage pathway involves recycling nicotinamide and nicotinamide-containing molecules such as nicotinamide riboside. The precursors are fed into the NAD+ biosynthetic pathwaythrough adenylation and phosphoribosylation reactions. These compounds can be found in the diet, where the mixture of nicotinic acid and nicotinamide are called vitamin B3 or niacin. These compounds are also produced within the body when the nicotinamide group is released from NAD+ in ADP-ribose transfer reactions."
What is the definition of Gluconeogenesis?,"Gluconeogenesis, which is essentially the reverse of glycolysis, results in the sythesis of glucose from non-carbohydrate substrates such as lactate, glycerol, and glucogenic amino acids. In animals, gluconeogenesis occurs primarily in the liver, and in the renal cortex to a lesser extent. This process occurs during periods of fasting or intense exercise. Gluconeogenesis is often associated with ketosis. Several non-carbohydrate carbon substrates can enter the gluconeogenesis pathway. One common substrate is lactic acid, formed during anaerobic respiration in skeletal muscle. Lactate may also come from red blood cells, which obtain energy solely from glycolysis as they have no membrane-bound organelles for aerobic respiration. Lactate is transported to the liver to be converted into pyruvate in the Cori cycle by lactate dehydrogenase. Pyruvate can then be used to generate glucose via gluconeogenesis. Many other compounds can also function as substrates for gluconeogenesis such as citric acid cycle intermediates (through conversion to oxaloacetate), amino acids other than lysine or leucine, and glycerol ."
What is the definition of Lactose Degradation?,"Lactose degradation (Lactose metabolism) shows the breakdown of alpha lactose into its constituent sugars, which are then utilized by the body as an energy source. Alpha-Lactose is the major sugar present in milk and the main source of energy supplied to the newborn mammalian in its mother’s milk. Lactose is also an important osmotic regulator of lactation. It is digested by the intestinal lactase, an enzyme expressed in newborns. Its activity declines following weaning. Lactase hydrolyzes alpha lactose into D-glucose and D-galactose, which are actively transported into the intestinal epithelial cells via the SGLT1 (GLUT1) cotransporter. GLUT1 actively transports glucose and galactose with 2 sodium ions. A sodium/potassium ATPase makes ATP by moving three sodium ions to the blood per two potassium ions that cross into the epithelial cell, giving the GLUT1 transporter energy to work. D-glucose and D-galactose diffuse into the blood, facilitated by the SLC2A2 transporter on the basolateral membrane on the intestinal epithelial cells. The sugars are then transported to liver."
What is the definition of Transfer of Acetyl Groups into Mitochondria?,"Acetyl-CoA is an important molecule, which is precursor to HMG CoA, which is a vital component in cholesterol and ketone synthesis. Acetyl CoA participates in the biosynthesis of fatty acids and sterols, in the oxidation of fatty acids and in the metabolism of many amino acids. It also acts as a biological acetylating agent. Acetyl-CoA is made in the mitochondria by metabolizing fatty acids, and the oxidation of pyruvate of acetyl-CoA. When the body has an excess of ATP, the energy in acetyl-Coa can be stored in the form of fatty acids. Acetyl-CoA must cross the mitochondrial membrane to the cytosol, where fatty acid synthesis takes place. Acetyl-CoA is combined with oxalacetic acid by the enzyme citrate synthase, creating citric acid. Citric acid is then transported out of the mitochondria, to the cytosol, where the enzyme citrate lyase converts citric acid back into acetyl-CoA and oxalacetic acid. Malate dehydrogenase reduces oxalacetic acid to malate, which then is either transported back into the mitochondria by the malate-alpha ketoglutarate transporter or oxidized to pyruvate by malic enzyme. Pyruvate can then be transported back into the mitochondria and undergo decarboxylation into oxalacetic acid. Malate can also be used to create NADH by the conversion of malate to oxalacetic acid by malate dehydrogenase."
What is the definition of Oxidation of Branched-Chain Fatty Acids?,"Fatty acid degradation in most organisms occurs primarily via the beta-oxidation cycle. In mammals, beta-oxidation occurs in both mitochondria and peroxisomes, whereas plants and most fungi harbor the beta-oxidation cycle only in the peroxisomes. Although the fatty acid oxidation scheme works neatly for even- numbered chain lengths, it can’t work completely for fatty acids that contain an odd number of carbons or branched chain fatty acids such as phytanic acid. Beta-oxidation of these compounds leads to propionyl-CoA and acetyl-CoA, rather than to two acetyl-CoA at the final step. The propionyl-CoA is not a substrate for the TCA cycle or other simple pathways. For example, phytanic acid, found in animal milk, can’t be oxidized directly by beta-oxidation because the addition of water is a problem at the branched beta-carbon. The first step in the digestion of this compound is the oxidation of the carbon by molecular oxygen. Then the original carboxyl group is removed as CO2, leaving a shorter chain. This chain can now be accommodated by the beta-oxidation reactions, because the new beta-carbon now lacks a methyl group. In mitochondria, the beta-oxidation pathway includes four reactions that occur in repeating cycles with each fatty acid molecule. In each cycle, a fatty acid is progressively shortened by two carbons as it is oxidized and its energy captured by the reduced energy carriers NADH and FADH2. At the end of each cycle of four reactions, one acetyl-CoA two-carbon unit is released from the end of the fatty acid, which then goes through another round of beta-oxidation, continuing to oxidize and shorten even-chain fatty acids until they are entirely converted to acetyl-CoA. The acetyl-CoA generated in beta-oxidation enters the TCA cycle, where it is further oxidized to CO2, producing more reduced energy carriers, NADH and FADH2. These carriers produced in the TCA cycle, along with those produced directly in beta-oxidation, transfer their energy to the electron transport chain where they drive the creation of the proton gradient that supports mitochondrial ATP production. Another destination of acetyl-CoA is the production of ketone bodies by the liver that are transported to tissues like the heart and brain for energy."
What is the definition of Inositol Phosphate Metabolism?,"Inositol phosphates are a group of molecules that are important for a number of cellular functions, such as cell growth, apoptosis, cell migration, endocytosis, and cell differentiation. Inositol phsosphates consist of an inositol (a sixfold alcohol of cyclohexane) phosphorylated at one or more positions. There are a number of different inositol phosphates found in mammals, distinguishable by the number and position of the phosphate groups. Inositol phosphate can be formed either as a product of phosphatidylinositol phosphate metabolism or from glucose 6-phosphate via the enzyme inositol-3-phosphate synthase 1. Conversion between the different types of inositol phosphates then occurs via a number of specific inositol phosphate kinases and phosphatases, which add (kinase) or remove (phosphatase) phosphate groups. The differing roles of the numerous inositol phosphates means that their metabolism must be tightly regulated. This is done via the localization and activation/deactivation of the various kinases and phosphatases, which can be found in the cytoplasm, nucleus or endoplasmic reticulum. The unphosphorylated inositol ring can be used to produce phosphoinositides through phosphatidylinositol phosphate metabolism."
What is the definition of Glycine and Serine Metabolism?,"This pathway describes the synthesis and breakdown of several small amino acids, including glycine, serine, and cysteine. All of these compounds share common intermediates and almost all can be biosynthesized from one another. Serine and glycine are not essential amino acids and can be synthesized from several routes. On the other hand, cysteine is a conditionally essential amino acid, meaning that it can be endogenously synthesized but insufficient quantities may be produced due to certain diseases or conditions. Serine is central to the synthesis and breakdown of the other two amino acids. Serine can be synthesized via glycerate, which can be converted into glycerate 3-phosphate (via glycerate kinase), which in turn is converted into phosphohydroxypyruvate by phosphoglycerate dehydrogenase and then phosphoserine (via phosphoserine transaminase) and finally to serine (via phosphoserine phosphatase). The serine synthesized via this route can be used to create cysteine and glycine through the homocysteine cycle. In the homocysteine cycle, cystathionine beta-synthase catalyzes the condensation of homocysteine and serine to give cystathionine. Cystathionine beta-lyase then converts this double amino acid to cysteine, ammonia, and alpha-ketoglutarate. Glycine is biosynthesized in the body from the amino acid serine. In most organisms, the enzyme serine hydroxymethyltransferase (SHMT) catalyzes this transformation using tetrahydrofolate (THF), leading to methylene THF and glycine. Glycine can be degraded via three pathways. The predominant pathway in animals involves the glycine cleavage system, also known as the glycine decarboxylase complex or GDC. This system is usually triggered in response to high concentrations of glycine. The system is sometimes referred to as glycine synthase when it runs in the reverse direction to produce glycine. The glycine cleavage system consists of four weakly interacting proteins: T, P, L and H-proteins. The glycine cleavage system leads to the degradation of glycine into ammonia and CO2. In the second pathway, glycine is degraded in two steps. The first step in this degradation pathway is the reverse of glycine biosynthesis from serine with serine hydroxymethyltransferase (SHMT). The serine generated via glycine is then converted into pyruvate by the enzyme known as serine dehydratase. In the third route to glycine degradation, glycine is converted into glyoxylate by D-amino acid oxidase. Glyoxylate is then oxidized by hepatic lactate dehydrogenase into oxalate in an NAD+-dependent reaction."
What is the definition of Porphyrin Metabolism?,"This pathway depicts the synthesis and breakdown of porphyrin. The porphyrin ring is the framework for the heme molecule, the pigment in hemoglobin and red blood cells. The first reaction in porphyrin ring biosynthesis takes place in the mitochondria and involves the condensation of glycine and succinyl-CoA by delta-aminolevulinic acid synthase (ALAS). Delta-aminolevulinic acid (ALA) is also called 5-aminolevulinic acid. Following its synthesis, ALA is transported into the cytosol, where ALA dehydratase (also called porphobilinogen synthase) dimerizes 2 molecules of ALA to produce porphobilinogen. The next step in the pathway involves the condensation of 4 molecules of porphobilinogen to produce hydroxymethylbilane (also known as HMB). The enzyme that catalyzes this condensation is known as porphobilinogen deaminase (PBG deaminase). This enzyme is also called hydroxymethylbilane synthase or uroporphyrinogen I synthase. Hydroxymethylbilane (HMB) has two main fates. Most frequently it is enzymatically converted into uroporphyrinogen III, the next intermediate on the path to heme. This step is mediated by two enzymes: uroporphyrinogen synthase and uroporphyrinogen III cosynthase. Hydroxymethylbilane can also be non-enzymatically cyclized to form uroporphyrinogen I. In the cytosol, the uroporphyrinogens (uroporphyrinogen III or uroporphyrinogen I) are decarboxylated by the enzyme uroporphyrinogen decarboxylase. These new products have methyl groups in place of the original acetate groups and are known as coproporphyrinogens. Coproporphyrinogen III is the most important intermediate in heme synthesis. Coproporphyrinogen III is transported back from the cytosol into the interior of the mitochondria, where two propionate residues are decarboxylated (via coproporphyrinogen-III oxidase), which results in vinyl substituents on the 2 pyrrole rings. The resulting product is called protoporphyrinogen IX. The protoporphyrinogen IX is then converted into protoporphyrin IX by another enzyme called protoporphyrinogen IX oxidase. The final reaction in heme synthesis also takes place within the mitochondria and involves the insertion of the iron atom into the ring system generating the molecule known heme b. The enzyme catalyzing this reaction is known as ferrochelatase. The largest repository of heme in the body is in red blood cells (RBCs). RBCs have a life span of about 120 days. When the RBCs have reached the end of their useful lifespan, the cells are engulfed by macrophages and their constituents recycled or disposed of.  Heme is broken down when the heme ring is opened by the enzyme known as heme oxygenase, which is found in the endoplasmic reticulum of the macrophages. The oxidation process produces the linear tetrapyrrole biliverdin, ferric iron (Fe3+), and carbon monoxide (CO). The carbon monoxide (which is toxic) is eventually discharged through the lungs. In the next reaction, a second methylene group (located between rings III and IV of the porphyrin ring) is reduced by the enzyme known as biliverdin reductase, producing bilirubin. Bilirubin is significantly less extensively conjugated than biliverdin. This reduction causes a change in the colour of the molecule from blue-green (biliverdin) to yellow-red (bilirubin). In hepatocytes, bilirubin-UDP-glucuronyltransferase (bilirubin-UGT) adds two additional glucuronic acid molecules to bilirubin to produce the more water-soluble version of the molecule known as bilirubin diglucuronide. In most individuals, intestinal bilirubin is acted on by the gut bacteria to produce the final porphyrin products, urobilinogens and stercobilins. These are excreted in the feces. The stercobilins oxidize to form brownish pigments which lead to the characteristic brown colour found in normal feces. Some of the urobilinogen produced by the gut bacteria is reabsorbed and re-enters the circulation. These urobilinogens are converted into urobilins that are then excreted in the urine which cause the yellowish colour in urine."
What is the definition of Galactose Metabolism?,"This pathway depicts the conversion of galactose into glucose, lactose, and other sugar intermediates that may be used for a range of metabolic process. Dietary sources of galactose are numerous, but some of the primary sources in the human diet can be found in milk and milk derivative products. This is because during digestion milk sugars and lactose are hydrolyzed into their molecular constituents (e.g. base monosaccharides). In milk, such monosaccharides include glucose and galactose. The metabolism of the sugar Galactose is occurs almost entirely in the liver, and its metabolism is the consequence of three steps or reactions. First, the phosphorylation of galactose is induced by a special enzyme with the predictable name, galactokinase, and produces galactose 1-phosphate. Second, this biproduct and a second molecule, UDP-glucose, undergo a reaction which leads to the formation of UDP-galactose and glucose 1-phosphate. Thus, this reaction produces 1 molecule of glucose 1-phosphate per molecule of galactose.This is mediated by the enzyme galactose-1-phosphate uridylyltransferase (GALT). The resulting UDP-galactose undergoes epimerization to form UDP-glucose via the enzyme UDP-galactose-4 epimerase (GALE). The UDP-glucose can be used in glucuronidation reactions and other pentose interconversions. In a reaction shared with other pathways, glucose 1-phosphate can be converted into glucose 6-phosphate. There are other pathways associated with galactose metabolism. For instance, galactose can be converted into UDP-glucose by the sequential activities of GALK, UDP-glucose pyrophosphorylase 2 (UGP2), and GALE. Galactose can also be reduced to galactitol by NADPH-dependent aldose reductase. Also shown in this pathway is the conversion of glucose to galactose vis a vis a different process to the ones described earlier. This pathway, called hexoneogenesis, allows mammary glands to produce galactose. It should be noted however, that despite the existence of this pathway of galactose production, the vast majority of galactose in breast milk is actually the result of direct uptake up from the blood, whereas only a small fraction, ~35%, is the result of this de novo process hexoneogenesis. Also depicted in this pathway are the conversions of other dietary di and tri-saccharides (raffinose, manninotriose, melibiose, stachyose) into galactose, glucose and fructose as well as and dietary sugar alcohols (melibitol, galactinol, galactosylglycerol) into sorbitol, myo-inositol, and glycerol. "
What is the definition of Pyrimidine Metabolism?,"Pyrimidines are heterocyclic aromatic organic compounds similar to benzene and pyridine. Cytosine, thymine, and uracil are pyrimidine derivatives. Synthesis of the pyrimidines is less complex than that of the purines, since the base is much simpler This pathway depicts a number of processes including pyrimidine nucleotide biosynthesis, pyrimidine degradation and pyrimidine salvage. Pyrimidine nucleotide biosynthesis begins with carbamoyl phosphate. The carbamoyl phosphate used for pyrimidine nucleotide synthesis is derived from glutamine and bicarbonate and is catalyzed by carbamoyl phosphate synthetase II (CPS-II). Subsequently carbamoyl phosphate is incorporated into the pyrimidine nucleotide biosynthesis pathway through the action of aspartate transcarbamoylase, ATCase which generates carbamoyl aspartate. This is then converted to dihydroorotic acid via carbamoyl aspartate dehydrogenase, which is then converted to orotic acid via dihydroorotate dehydrogenase. The enzyme orotate phosphoribosyltransferase incorporate PRPP to produce orotidine monophosphate (OMP) which is converted to UMP (uridine monopohophsate) via orotidine-5’-phosphate carboxylase. Following completion of UMP synthesis it can be phosphorylated to UTP and utilized as a substrate for CTP synthase for the synthesis of CTP. Specifically, UMP is phosphorylated twice to yield UTP. The first phosphorylation is catalyzed by uridylate kinase and the second by ubiquitous nucleoside diphosphate kinase. Finally UTP is aminated by the action of CTP synthase, generating CTP. Uridine nucleotides are also the precursors for de novo synthesis of the thymine nucleotides. The de novo pathway to thymidine nucleotdie synthesis first requires the use of deoxyUMP from the metabolism of either UDP or CDP. The deoxyUMP is converted to deoxyTMP by the action of thymidylate synthase. The methyl group is donated by N5,N10-methylene THF. In order for the thymidylate synthase reaction to continue, THF must be regenerated from DHF. This is accomplished through the action of dihydrofolate reductase (DHFR). THF is then converted to N5,N10-THF via the action of serine hydroxymethyl transferase. The synthesis of pyrimidines differs in two significant ways from that of purines. First, the ring structure is assembled as a free base, not built upon PRPP. Second, there is no branch in the pyrimidine synthesis pathway. The salvage pathway to dTTP synthesis involves the enzyme thymidine kinase which can use either thymidine or deoxyuridine as a substrate. Uracil can be salvaged to form UMP through the concerted action of uridine phosphorylase and uridine kinase. Formation of dTMP, by salvage of dTMP requires the action of thymine phosphorylase and thymidine kinase while the salvage of deoxycytidine is catalyzed by deoxycytidine kinase. Deoxyadenosine and deoxyguanosine are also substrates for deoxycytidine kinase. In terms of the catabolism of pyrimidines, they are ultimately degraded to CO2, H2O, and urea. Cytosine can be broken down to uracil which can be further broken down to N-carbamoyl-beta-alanine and then to beta-alanine. Thymine is broken down into β-aminoisobutyrate. The β-alanine and β-aminoisobutyrate serve as -NH2 donors in the transamination of α-ketoglutarate to glutamate. A subsequent reaction converts the products to malonyl-CoA or methylmalonyl-CoA (which is converted to succinyl-CoA and can be shunted to the TCA cycle)."
What is the definition of Beta Oxidation of Very Long Chain Fatty Acids?,"Fatty acid degradation in most organisms occurs primarily via the beta-oxidation cycle.  In mammals, beta-oxidation occurs in both mitochondria and peroxisomes, whereas plants and most fungi harbor the beta-oxidation cycle only in the peroxisomes.  However, the oxidation ceases at octanyl CoA.  It is believed that very long chain (greater than C-22) fatty acids undergo initial oxidation in peroxisomes which is followed by mitochondrial oxidation.  One significant difference is that oxidation in peroxisomes is not coupled to ATP synthesis.  Instead, the high-potential electrons are transferred to O2, which yields H2O2.  The enzyme catalase, found exclusively in peroxisomes, converts the hydrogen peroxide into water and oxygen.  Peroxisomal β-oxidation also requires enzymes specific to the peroxisome and to very long fatty acids.  There are three key differences between the enzymes used for mitochondrial and peroxisomal β-oxidation: beta-oxidation in the peroxisome requires the use of a peroxisomal carnitine acyltransferase (instead of carnitine acyltransferase I and II used by the mitochondria) for transport of the activated acyl group into the peroxisome.  The first oxidation step in the peroxisome is catalyzed by the enzyme acyl CoA oxidase.  The beta-ketothiolase used in peroxisomal beta-oxidation has an altered substrate specificity, different from the mitochondrial beta-ketothiolase.  In mitochondria, the beta-oxidation pathway includes four reactions that occur in repeating cycles with each fatty acid molecule.  In each cycle, a fatty acid is progressively shortened by two carbons as it is oxidized and its energy captured by the reduced energy carriers NADH and FADH2.  At the end of each cycle of four reactions, one acetyl-CoA two-carbon unit is released from the end of the fatty acid, which then goes through another round of beta-oxidation, continuing to oxidize and shorten even-chain fatty acids until they are entirely converted to acetyl-CoA.  The acetyl-CoA generated in beta-oxidation enters the TCA cycle, where it is further oxidized to CO2, producing more reduced energy carriers, NADH and FADH2.  These carriers produced in the TCA cycle, along with those produced directly in beta-oxidation, transfer their energy to the electron transport chain where they drive the creation of the proton gradient that supports mitochondrial ATP production.  Another destination of acetyl-CoA is the production of ketone bodies by the liver that are transported to tissues like the heart and brain for energy. "
What is the definition of Urea Cycle?,"About 80% of the body’s excreted nitrogen is in the form of urea which is also largely made in the liver, in a series of reactions that are distributed between the mitochondrial matrix and the cytosol. The series of reactions that form urea is known as the Urea Cycle (Ornithine Cylce) or the Krebs-Henseleit Cycle. The essential features of the urea cycle reactions and their metabolic regulation are as follows: Arginine from the diet or from protein breakdown is cleaved by the cytosolic enzyme arginase, generating urea and ornithine. In subsequent reactions of the urea cycle a new urea residue is built on the ornithine, regenerating arginine and perpetuating the cycle. Ornithine arising in the cytosol is transported to the mitochondrial matrix, where ornithine transcabamoylase catalyzes the condensation of ornithine with carbamoyl phosphate, producing citrulline. The energy for the reaction is provided by the high-energy anhydride of carbamoyl phosphate. The product, citrulline, is then transported to the cytosol, where the remaining reactions of the cycle take place. The synthesis of citrulline requires a prior activation of carbon and nitrogen as carbamoyl phosphate (CP). The activation step requires 2 equivalents of ATP and the mitochondrial matrix enzyme carbamoyl phosphate synthetase-I (CPS-I). In a 2-step reaction, catalyzed by cytosolic argininosuccinate synthetase, citrulline and aspartate are condensed to form argininosuccinate. The reaction involves the addition of AMP (from ATP) to the amido carbonyl of citrulline, forming an activated intermediate on the enzyme surface (AMP-citrulline), and the subsequent addition of aspartate to form argininosuccinate. Arginine and fumarate are produced from argininosuccinate by the cytosolic enzyme argininosuccinate lyase. In the final step of the cycle arginase cleaves urea from aspartate, regenerating cytosolic ornithine, which can be transported to the mitochondrial matrix for another round of urea synthesis. The fumarate, generated via the action of arginiosuccinate lyase, is reconverted to aspartate for use in the argininosuccinate synthetase reaction."
What is the definition of Tryptophan Metabolism?,"This pathway depicts the metabolic reactions and pathways associated with tryptophan metabolism in animals. Tryptophan is an essential amino acid. This means that it cannot be synthesized by humans and other mammals and therefore must be part of the diet. Unlike animals, plants and microbes can synthesize tryptophan from shikimic acid or anthranilate. As one of the 20 proteogenic amino acids, tryptophan plays an important role in protein biosynthesis through the action of tryptophanyl-tRNA synthetase. As shown in this pathway, tryptophan can be linked to the tryptophanyl-tRNA via either the mitochondrial or cytoplasmic tryptophan tRNA ligases. Also shown in this pathway map is the conversion of tryptophan to serotonin (a neurotransmitter). In this process, tryptophan is acted upon by the enzyme tryptophan hydroxylase, which produces 5-hydroxytryptophan (5HTP). 5HTP is then converted into serotonin (5-HT) via aromatic amino acid decarboxylase. Serotonin, in turn, can be converted into N-acetyl serotonin (via serotonin-N-acetyltransferase) and then melatonin (a neurohormone), via 5-hydroxyindole-O-methyltransferase. The melatonin can be converted into 6-hydroxymelatonin via the action of cytochrome P450s in the endoplasmic reticulum. Serotonin has other fates as well. As depicted in this pathway it can be converted into N-methylserotonin via Indolethylamine-N-methyltransferase (INMT) or it can be converted into formyl-5-hydroxykynurenamine via indoleamine 2,3-dioxygenase. Serotonin may also be converted into 5-methoxyindoleacetate via a series of intermediates including 5-hydroxyindoleacetaldehyde and 5-hydroxyindoleacetic acid. Tryptophan can be converted or broken down into many other compounds as well. It can be converted into tryptamine via the action of aromatic amino acid decarboxylase. The resulting tryptamine can then be converted into indoleacetaldehyde via kynurenine 3-monooxygenase and then into indoleacetic acid via the action of aldehyde dehydrogenase. Tryptophan also leads to the production of a very important compound known as kynurenine. Kynurenine is synthesized via the action of tryptophan 2,3-dioxygnase, which produces N-formylkynurenine. This compound is converted into kynurenine via the enzyme known as kynurenine formamidase (AFMID). Kynurenine has at least 3 fates. First, kynurenine can undergo deamination in a standard transamination reaction yielding kynurenic acid. Secondly, kynurenine can undergo a series of catabolic reactions (involving kynureninase and kynurenine 3-monooxygenase) producing 3-hydroxyanthranilate plus alanine. In this reaction, kynureninase catabolizes the conversion of kynurenine into anthranilic acid while kynurenine—oxoglutarate transaminase (also known as kynurenine aminotransferase or glutamine transaminase K, GTK) catabolizes its conversion into kynurenic acid. The action of kynurenine 3-hydroxylase on kynurenic acid leads to 3-hydroxykynurenine. The oxidation of 3-hydroxyanthranilate converts it into 2-amino-3-carboxymuconic 6-semialdehyde, which has two fates. It can either degrade to form acetoacetate or it can cyclize to form quinolate. Most of the body’s 3-hydroxyanthranilate leads to the production of acetoacetate (a ketone body), which is why tryptophan is also known as a ketogenic amino acid. An important side reaction in the liver involves a non-enzymatic cyclization into quinolate followed by transamination and several rearrangements to yield limited amounts of nicotinic acid, which leads to the production of a small amount of NAD+ and NADP+."
What is the definition of Retinol Metabolism?,"Retinol is part of the vitamin A family, and is known as vitamin A1, and in a dietary context it is a type of preformed vitamin A. As with other preformed vitamin A's, it can be obtained from animal sources, with the highest concentrations coming from animal liver, with other sources being fish and dairy products. Other forms of vitamin A include retinal, its aldehyde form, retinoic acid, its acid form, and reinyl ester, its ester form. Additionally, herbivores and omnivores can obtain provitamin A from things such as alpha-, beta- and gamma-carotene, which can be converted to retinol as needed by the body.Retinol can be used in the body to form retinyl ester via diacylglycerol O-acyltransferase 1 and acyl-CoA wax akcohol acyltransferase 1 which both use acetyl-CoA as a reactant and produce CoA in addition to the retinyl ester. IT can also be produced by lecithin retinol acyltransferase, which uses a phosphatidylcholine molecule, and produces glycerophosphocholine. All of these reactions take place in the endoplasmic reticulum. Retinyl ester can also be converted back to retinol by patatin-like phospholipase domain-containing protein 4 as the enzyme in a reaction that also converts a diacylglycerol to a triacylglycerol. Alternately, retinyl ester can interact with retinoid isomerohydrolase to form 11-cis-retinol.11-cis-retinol can be converted to retinyl palmitate by either diacylglycerol O-acyltransferase 1 or acyl-CoA wax alcohol acyltransferase 1 in the endoplasmic reticulum, which both add the acetyl group onto 11-cis-retinol, forming CoA as a side product. Alternatively, retinyl palmitate can be formed by lecithin retinol acyltransferase, which takes a molecule of phosphatidylcholine, and produces glycerophosphocholine in addition to the retinyl palmitate.Rhodopsin, a photosensitive protein found in the retina, can be converted to bathorhodopsin, which has previously been known as prelumirhodopsin. This conversion is caused by the absorption of light into the retinal portion of the protein complex, which then isomerizes, forcing the protein to change shape to accomodate this. Bathorhodopsin almost immediately converts to lumirhodopsin, which then converts to metarhodopsin, and at this point, the retinal is in its all-trans configuration. All-trans retinal can also be formed from 11-cis-retinaldehyde, also known as 11-cis-retinal, via dehydrogenase/reductase SDR family member 4 or retinol dehydrogenase 12 in the cell, as well as retinol dehydrogenases 8 and 16, short-chain dehydrogenase/reductase 3 or dehydrogenase/reductase SRD family member 9 in the endoplasmic reticulum. Two molecules of retinal can also be formed from beta-carotene, after its interaction with betabeta-carotene 15,15'-monooxygenase, or from retinol via retinol dehydrogenase 11 in the endoplasmic reticulum. Additionally, 11-cis-retinaldehyde can reversibly form all-trans retinal via interaction with alcohol dehydrogenase 1A. 11-cis-retinaldehyde is also in the conformation found in rhodopsin, and can be used to create more rhodopsin complexes. 11-cis-retinaldehyde can also be converted to 11-cis-retinol by retinol dehydrogenase in the endoplasmic reticulum.Retinol can also isomerize and form 9-cis-retinol, which can then be reversibly oxidized to form 9-cis-retinal by interacting with either retinol dehydrogenase 11 or dehydrogenase/reductase SDR family member 4. 9-cis-retinal can then be further oxidized to 9-cis-retinoic acid by retinal dehydrogenase 1 or 2. 9-cis-retinoic acid can also be formed from the isomerization of all-trans retinoic acid, which in turn is formed by the oxidation of retinol by either of retinal dehydrogenase 1 or 2.All-trans retinoic acid can also be glucuronidated to form retinoyl b-glucuronide, in a reaction catalyzed by a multiprotein chaperone complex including UDP-glucuronosyltransferase 1-1 in the endoplasmic reticulum. Finally, in the endoplasmic reticulum, all-trans-retinoic acid can undergo epoxidation to form all-trans-5,6-epoxyretinoic acid by interaction with a complex of cytochrome P450 proteins, or hydroxylated to either 4-hydroxyretinoic acid or all-trans-18-hydroxyretinoic acid by cytochrome P450 26A1. In one last reqction, 4-hydroxyretinoic acid can be oxidized once again by cytochrome P450 26A1 to form 4-oxo-retinoic acid."
What is the definition of Mitochondrial Electron Transport Chain?,"The electron transport chain in mitochondria leads to the transport of hydrogen ions across the inner membrane of the mitochndria, and this proton gradient is eventually used in the production of ATP. Electrons travel down a chain of electron carriers in the inner mitochondrial membrane, ending with oxygen.The outer membrane of the mitochondrion is permeable to ions and other small molecules  and nothing in this pathway requires a specific transporter to enter into the intermembrane space. However, the inner membrane is only permeable to water, oxygen and carbon dioxide, and all other molecules, including protons, require transport proteins. Phosphate is able to enter the mitochondrial matrix via the glucose-6-phosphate translocase, and ADP is able to enter the matrix as ATP leaves it via the ADP/ATP translocase 1 protein.Electrons donated by NADH can enter the electron transport chain as NADH dehydrogenase, known as complex I, facilitates their transfer to ubiquinone, also known as coenzyme Q10. As this occurs, the coenzyme Q10 becomes reduced to form ubiquinol, and protons are pumped from the intermembrane space to the matrix.Lower energy electrons can also be donated to complex II, which includes succinate dehydrogenase and contains FAD. These electrons move from succinic acid to the FAD in the enzyme complex, and then to coenzyme Q10, which is reduced to ubiquinol. Throughout this, succinic acid from the citric acid cycle is converted to fumaric acid, which then returns to the citric acid cycle. This step, unlike the others in the electron transport chain, does not result in any protons being pumped from the matrix to the intermembrane space.Regardless of which complex moved the electrons to coenzyme Q10, the cytochrome b-c1 complex, also known as complex III, catalyzes the movement of electrons from ubiquinol to cytochrome c, oxidizing ubiquinol to ubiquinone and reducing cytochrome c. This process also leads to the pumping of hydrogen ions into the intermembrane space. Finally, the transfer of electrons from the reduced cytochrome c is catalyzed by cytochrome c oxidase, also known as complex IV of the electron transport chain. This reaction oxidizes cytochrome c for further electron transport, and transfers the electrons to oxygen, forming molecules of water. This reaction also allows protons to be pumped across the membrane.The proton gradient that is built up through the electron transport chain allows protons to flow through the ATP synthase proteins in the mitochondrial inner membrane, providing the energy required to synthesize ATP from ADP."
What is the definition of Threonine and 2-Oxobutanoate Degradation?,"  2-oxobutanoate, also known as 2-Ketobutyric acid, is a 2-keto acid that is commonly produced in the metabolism of amino acids such as methionine and threonine.  Like other 2-keto acids, degradation of 2-oxobutanoate occurs in the mitochondrial matrix and begins with oxidative decarboxylation to its acyl coenzyme A derivative, propionyl-CoA.  This reaction is mediated by a class of large, multienzyme complexes called 2-oxo acid dehydrogenase complexes.  While no 2-oxo acid dehydrogenase complex is specific to 2-oxobutanoate, numerous complexes can catalyze its reaction.  In this pathway the branched-chain alpha-keto acid dehydrogenase complex is depicted.  All 2-oxo acid dehydrogenase complexes consist of three main components: a 2-oxo acid dehydrogenase (E1) with a thiamine pyrophosphate cofactor, a dihydrolipoamide acyltransferase (E2) with a lipoate cofactor, and a dihydrolipoamide dehydrogenase (E3) with a flavin cofactor.  E1 binds the 2-oxobutanoate to the lipoate on E2, which then transfers the propionyl group to coenzyme A, producing propionyl-CoA and reducing the lipoate.  E3 then transfers protons to NAD in order to restore the lipoate.  Propionyl-CoA carboxylase transforms the propionyl-CoA to S-methylmalonyl-CoA, which is then converted to R-methylmalonyl-CoA via methylmalonyl-CoA epimerase.  In the final step, methylmalonyl-CoA mutase acts on the R-methylmalonyl-CoA to produce succinyl-CoA. "
What is the definition of Fatty Acid Biosynthesis?,"The biosynthesis of fatty acids primarily occurs in liver and lactating mammary glands. The entire synthesis process which produces palmitic acid occurs on a multifunctional dimeric protein Fatty Acid Synthase (FA) in the cytosol. The production of palmitic acid can be summarized as the successive addition of two carbons to an initial acetyl moiety primer. After 7 cycles palimitic acid is released.  The synthesis starts with the sequential transfer of a primer substrate, acetyl-CoA, to the nucleophilic serine residue of the acyltransferase domain of FA. The acetyl moiety is then transferred to the Acyl Carrier Protein (ACP) domain of FA, then finally to the active site of the beta-ketoacyl synthase domain. A chain extender substrate, molonyl-CoA, is transferred to the nucleophilic serine residue of the acyltransferase domain and subsequently to the ACP domain. The acetyl moiety is extend by a condensation reaction, catalysed by the beta-ketoacyl synthase domain, that produces a new Carbon-Carbon bound, this reaction is coupled to a decarboxylation resulting in the production of carbon dioxide. Subsequently beta-ketoacyl condensation product is reduced to a saturated acyl moiety through the step wise action on the beta-ketoacyl reductase, beta-hydroxyacyl dehydrase and enoyl reductase domains respectively. This saturated acyl moiety is then transfer back to the active site of the beta-ketoacyl synthase domain, another molonyl-CoA is loaded and the process repeats. The addition of molonyl moieties occurs 7 times after which the final product is released by that action of thioesterase domain. The final product is 16 carbon long palmitic acid."
What is the definition of Phosphatidylinositol Phosphate Metabolism?,"Phosphatidylinositol phosphates, or phosphoinositides, are intracellular signaling lipids. Seven different phosphoinositides have been identified in mammals, each distinguished by the number and/or position of the phosphate groups on the inositol ring. The inositol can be mono-, di-, or triphosphorylated, with the remaining phosphoinositides being isomers of these three forms. Phosphoinositides regulate a variety of signal transduction processes, thus playing a number of important roles in the cell, such as actin cytoskeletal reorganization, membrane transport, and cell proliferation. They may also affect protein localization, aggregation, and activity by acting as secondary messengers. The ability of the cell to recognize the different types of phosphoinositides as different cellular signals means that their synthesis and metabolism must be tightly regulated. Synthesis begins with the attachment of an inositol phosphate head group to diacylglycerol via a phospholipase C enzyme, creating a phosphoinositide. Conversion between the different types of phosphoinositides is then done by a number of specific phosphoinositide kinases and phosphatases, which add (kinase) and remove (phosphatase) phosphates from the inositol ring. The specific localization and regulation of the phosphoinositide kinases and phosphatases thus controls the activity of the phosphoinositides. While the phosphoinositides are always located in the membrane, their particular kinases and phosphatases may be found in the cytoplasm or in the membrane of the cell or cell organelles."
What is the definition of Trehalose Degradation?,"Trehalose, also known as mycose or tremalose, is a sugar consisting of two 1-1 alpha bonded glucose molecules. It is produced by some plants, bacteria, fungi and invertebrates, and can be used as a source of energy, such as for flight in insects, and as a survival mechanism to avoid freezing and dehydration.After ingestion in the intestine lumen, trehalose can interact with trehalase, which exists in the brush border of the cells there. In a reaction that also requires a water molecule, it is broken. These are then transported into the epithelial cells along with a sodium ion by a sodium/glucose cotransporter, which can bring glucose up its gradient along with sodium moving down its gradient. Once inside the cell, the glucose can then be transported out of the basolateral membrane by a solute carrier family 2 facilitated glucose transporter. From there, the glucose enters the blood stream, and is transported to liver hepatocytes. Once in the liver, glucokinase can use the energy and phosphate from a molecule of ATP to form glucose-6-phosphate, which then goes on to start the process of glycolysis."
What is the definition of Plasmalogen Synthesis?,"Plasmalogens are a class of phospholipids found in animals.  Plasmalogens are thought to influence membrane dynamics and fatty acid levels, while also having roles in intracellular signalling and as antioxidants.  Plasmalogens consist of a glycerol backbone with an vinyl-ether-linked alkyl chain at the sn-1 position, an ester-linked long-chain fatty acid at the sn-2 position, and a head group attached to the sn-3 position through a phosphodiester linkage.  It is the vinyl-ether-linkage that separates plasmalogens from other phospholipids.   Plasmalogen biosynthesis begins in the peroxisomes, where the integral membrane protein dihydroxyacetone phosphate acyltransferase (DHAPAT) catalyzes the esterification of the free hydroxyl group of dihydroxyacetone phosphate (DHAP) with a molecule any of long chain acyl CoA.  Next, alkyl-DHAP synthase, a peroxisomal enzyme associated with DHAPAT, replaces the fatty acid on the DHAP with a long chain fatty alcohol.  The third step of plasmalogen biosynthesis is catalyzed by the enzyme acyl/alkyl-DHAP reductase, which is found in the membrane of both the peroxisome and endoplasmic reticulum (ER).  Acyl/alkyl-DHAP reductase uses NADPH as a cofactor to reduce the ketone of the 1-alkyl-DHAP using a classical hydride transfer mechanism.  The remainder of plasmalogen synthesis occurs using enzymes in the ER.  Lysophosphatidate acyltransferases (LPA-ATs) transfer the acyl component of a polyunsaturated acyl-CoA to the the 1-alkyl-DHAP, creating a 1-alkyl-2-acylglycerol 3-phosphate.  The phosphate is then removed by lipid phosphate phosphohydrolase I (PAP-I), and the head group is attached by a choline/ethanolaminephosphotransferase.  The majority of plasmalogens have either ethanolamine or choline as a headgroup, although a small amount of serine and inositol-linked ether-phospholipids can also be found.  In the final step, the vinyl-ether linkage is created by plasmanylethanolamine desaturase, which catalyzes the formation of a double bond in the alkyl chain of the plasmalogen. "
What is the definition of Mitochondrial Beta-Oxidation of Short Chain Saturated Fatty Acids?,"Beta-oxidation is the major degradative pathway for fatty acid esters in humans. Fatty acids and their CoA esters are found throughout the body, playing roles such as components of cellular lipids, regulators of enzymes and membrane channels, ligands for nuclear receptors, precursor molecules for hormones, and signalling molecules. Beta-oxidation occurs in the peroxisomes and mitochondria, the latter of which is depicted here. Whether beta-oxidation starts in the mitochondria or the peroxisome depends on the length of the fatty acid. Medium to long chain fatty acids go directly to the mitochondria, whereas very long chain fatty acids (>22 carbons) may be first metabolized down to octanyl-CoA in the peroxisomes and then transported to the mitochondria for the remainder of the oxidation. Beta-oxidation begins with fatty acids first being activated by an acyl-coenzyme A synthetase. This process uses ATP to produce a reactive fatty acyl adenylate which then reacts with coenzyme A to produce a fatty acyl-CoA. Short and medium chain fatty acids can enter the mitochondria directly via diffusion where they are activated in the mitochondrial matrix by acyl-coenzyme A synthetases. Long chain fatty acids must be activated in the outer mitochondrial membrane then transported as a carnatine complex into the mitochondria. A double bond is formed between C-2 and C-3 to produce trans-Δ2-enoyl-CoA which is catalyzed by acyl-CoA-dehydrogenases in the mitochondria. Enoyl CoA hydratase then hydrates the double bond between C-2 and C-3 to produce a L-beta-hydroxyacyl CoA which then has its hydroxyl group converted to a keto group to produce beta-ketoacyl CoA. Finally, the beta-ketoacyl CoA is cleaved by beta-ketothiolase and a thiol group is inserted between C-2 and C-3 to reduce the acyl-CoA and produce acetyl-CoA. Acetyl-CoA can then enter the citric acid cycle. "
What is the definition of Mitochondrial Beta-Oxidation of Medium Chain Saturated Fatty Acids?,"Beta-oxidation is the major degradative pathway for fatty acid esters in humans. Fatty acids and their CoA esters are found throughout the body, playing roles such as components of cellular lipids, regulators of enzymes and membrane channels, ligands for nuclear receptors, precursor molecules for hormones, and signalling molecules. Beta-oxidation occurs in the peroxisomes and mitochondria, the latter of which is depicted here. Whether beta-oxidation starts in the mitochondria or the peroxisome depends on the length of the fatty acid. Medium to long chain fatty acids go directly to the mitochondria, whereas very long chain fatty acids (>22 carbons) may be first metabolized down to octanyl-CoA in the peroxisomes and then transported to the mitochondria for the remainder of the oxidation.  Beta-oxidation begins with activation of fatty acids by an acyl-coenzyme A synthetase. ATP is used to produce reactive fatty acyl adenylate that can then react with coenzyme A to produce a fatty acyl-CoA. Short and medium chain fatty acids can enter the mitochondria directly via diffusion where they are activated in the mitochondrial matrix by acyl-coenzyme A synthetases. In the first step of the beta-oxidation cycle, a double bond between C-2 and C-3 is formed, producing a trans-Δ2-enoyl-CoA. This is catalyzed by acyl-CoA-dehydrogenases in the mitochondria, which have forms specific to the different lengths of fatty acids. In the second step, enoyl CoA hydratase hydrates the newly formed double bond between C-2 and C-3, producing an L-beta-hydroxyacyl CoA. Next, L-beta-hydroxyacyl CoA dehydrogenase converts the hydroxyl group into a keto group, producing a beta-ketoacyl CoA. In the fourth and final step, the enzyme beta-ketothiolase cleaves the β-ketoacyl CoA and inserts the thiol group of another CoA between C-2 and C-3, reducing the acyl-CoA by 2 carbons and generating acetyl-CoA. The final two steps also have enzymatic forms specific to short chain fatty acids. Additionally, there is a trifunctional protein complex with enzymatic activity capable of performing all of the final 3 steps (hydratase, dehydrogenase, thiolase) in medium to very long chain fatty acids. This four step cycle repeats, removing 2 carbons from the fatty acid each time until it becomes acetyl-CoA. Acetyl-CoA is necessary for the citric acid cycle, among other cellular processes."
What is the definition of Mitochondrial Beta-Oxidation of Long Chain Saturated Fatty Acids?," Fatty acids and their CoA esters are found throughout the body, playing roles such as components of cellular lipids, regulators of enzymes and membrane channels, ligands for nuclear receptors, precursor molecules for hormones, and signalling molecules.  Beta-oxidation occurs in the peroxisomes and mitochondria, the latter of which is depicted here.  Whether beta-oxidation starts in the mitochondria or the peroxisome depends on the length of the fatty acid.  Medium to long chain fatty acids go directly to the mitochondria, whereas very long chain fatty acids (>22 carbons) may be first metabolized down to octanyl-CoA in the peroxisomes and then transported to the mitochondria for the remainder of the oxidation.   Beta-oxidation begins with activation of fatty acids by an acyl-coenzyme A synthetase.  ATP is used to produce reactive fatty acyl adenylate that can then react with coenzyme A to produce a fatty acyl-CoA.  Short and medium chain fatty acids can enter the mitochondria directly via diffusion where they are activated in the mitochondrial matrix by acyl-coenzyme A synthetases.  In the first step of the beta-oxidation cycle, a double bond between C-2 and C-3 is formed, producing a trans-Δ2-enoyl-CoA.  This is catalyzed by acyl-CoA-dehydrogenases in the mitochondria, which have forms specific to the different lengths of fatty acids.  In the second step, enoyl CoA hydratase hydrates the newly formed double bond between C-2 and C-3, producing an L-beta-hydroxyacyl CoA.  Next, L-beta-hydroxyacyl CoA dehydrogenase converts the hydroxyl group into a keto group, producing a beta-ketoacyl CoA.  In the fourth and final step, the enzyme beta-ketothiolase cleaves the β-ketoacyl CoA and inserts the thiol group of another CoA between C-2 and C-3, reducing the acyl-CoA by 2 carbons and generating acetyl-CoA.  The final two steps also have enzymatic forms specific to short chain fatty acids.  Additionally, there is a trifunctional protein complex with enzymatic activity capable of performing all of the final 3 steps (hydratase, dehydrogenase, thiolase) in medium to very long chain fatty acids.  This four step cycle repeats, removing 2 carbons from the fatty acid each time until it becomes acetyl-CoA.  Acetyl-CoA is necessary for the citric acid cycle, among other cellular processes. "
What is the definition of Acute Intermittent Porphyria?,"Acute intermittent porphyria (AIP), the second most common form of porphyria, is caused by a defect in the HMBS gene which codes for porphobilinogen deaminase. A defect in this enzyme results in accumulation of 5-aminolevulinic acid or porphobilinogen in both urine and serum. Most Patients are completely free of symptoms between attacks. Symtpoms include abdominal pain, constipation, vomitting, hypertension, muscle weakness, seizures, delirium, coma, and depression. A high-carbohydrate diet is typically recommended; in severe attacks, a glucose 10% infusion is recommended, which may aid in recovery."
What is the definition of Porphyria Variegata (PV)?,"Porphyria variegata (PV) is caused by a defect in the PPOX gene which codes for protoporphyrinogen oxidase. A defect in this enzyme results in accumulation of the porphyrin precursors porphobilinogen and 5-aminolevulinic acid in plasma; increase of fecal and urinary levels of porphyrin and coproporphyrin. Symtpoms include abdominal pain, vomiting, diarrhea, constipation, muscle weakness, seizures, and mental changes such as anxiety and hallucinations. Some people with variegate porphyria have skin that is overly sensitive to sunlight. Areas of skin exposed to the sun develop severe blistering, scarring, changes in pigmentation, and increased hair growth."
What is the definition of Congenital Erythropoietic Porphyria (CEP) or Gunther Disease?,"Congenital Erythropoietic Porphyria (CEP) or Gunther Disease is a rare inborn error of porphyrin-heme synthesis inherited that is as an autosomal recessive trait. This disorder of bone marrow heme synthesis is caused by a defect in the UROS gene which codes for uroporphyrinogen-III synthase. This enzyme is involved in the fourth step of porphyrin metabolism, involved in the conversion of hydroxymethyl bilane into uroporphyrinogen III. Its defect results in accumulation of uroporphyrin III, coproporphyrin III and porphyrins; Uroporphyrin I in erythrocytes. Symptoms and signs include blistering and fragility of light-exposed skin, discolored urine, concomitant jaundice, reddish color teeth. The severe loss of bone with subsequent contractures and deformities occurs in most adults with erythropoietic porphyria."
What is the definition of Adrenal Hyperplasia Type 3 or Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency?,"Adrenal hyperplasia type 3, also called Congenital adrenal hyperplasia due to 21-hydroxylase deficiency, is caused by a defect in the CYP21A2 gene which codes for Steroid 21-hydroxylase (21-hydroxylase). Steroid 21-hydroxylase catalyzes hydroxylation of 17-hydroxyprogesterone to 11-deoxycortisol in the glucocorticoid pathway from pregnenolone to cortisol. It also catalyzes hydroxylation of progesterone to 11-deoxycorticosterone (DOC) in the mineralocorticoid pathway on its way from pregnenolone to aldosterone. A defect in this enzyme results in accumulation of 17-Hydroxyprogesterone, progesterone and 17a-Hydroxypregnenolone, androstenedione, and testosterone; decreased levels of cortexolone, deoxycorticosterone, aldosterone and cortisol. Symptoms include salt-wasting crises in infancy due to the lack of aldosterone, like spitting, poor weight gain, vomiting, severe dehydration, and circulatory collapse. The high level of testosterone results in virilization and genital ambiguity of female infants."
What is the definition of Congenital Lipoid Adrenal Hyperplasia (CLAH) or Lipoid CAH?,"Congenital lipoid adrenal hyperplasia (CLAH; Steroid 20-22 desmolase deficiency; lipoid CAH) is caused by a defect in the CYP11A1 gene which codes for mitochondrial cholesterol side-chain cleavage enzyme. Cholesterol side-chain cleavage enzyme convertes cholesterol to pregnenolone in adrenal cortisol synthesis of all steroid hormones. A defect in this enzyme results in in impaired synthesis of all three categories of adrenal steroids (cortisol, mineralocorticoids, sex steroids) and high levels of adrenocorticotropic hormone (ACTH). Symptoms include poor feeding, vomiting, dehydration, hypotension, hyponatremia, hyperkalemia, hypoglycemia, hyperpigmentation. Sex steroid deficiency can result in ambiguous genitalia. Patients need the mineral replacement and extra glucocorticoid. XX female patients can use estrogen replacement at or after puberty. For XY patients, the testes are uniformly nonfunctional and they are undescended, are removed when the diagnosis is made due to the risk of cancer development in these tissues."
What is the definition of Adrenal Hyperplasia Type 5 or Congenital Adrenal Hyperplasia Due to 17 alpha-Hydroxylase Deficiency?,"Adrenal hyperplasia type 5 (AH5; Congenital Adrenal Hyperplasia due to 17 Alpha hydroxylase Deficiency) is a form of congenital adrenal hyperplasia. It is caused by a defect in the CYP17A1 gene which codes for Steroid 17-alpha-hydroxylase/17,20 lyase. These 2 enzymes convert pregnenolone and progesterone to their 17-hydroxy forms in steroidogenesis and mediate three key transformations in cortisol and sex steroid synthesis. A defect in 17-alpha-hydroxylase results in decreased synthesis of both cortisol and sex steroids; increase in mineralocorticoids. Common symptoms include mild hypocortisolism, ambiguous genitalia in genetic males or failure of the ovaries to function at puberty in genetic females, and hypertension. Hypertension and mineralocorticoid excess is treated with glucocorticoid replacement. Genetically female patients need female hormone replacement to induce puberty and regulate menses. Surgery may be needed for males with ambiguous genitalia. Testosterone must be replaced for genetically males (XY) to induce puberty and continued throughout adult life."
What is the definition of Alkaptonuria?,"Alkaptonuria (Homogentisic acid oxidase deficiency) is an autosomal recessive disease caused by a mutation in the HGD gene which codes for homogentisate 1,2-dioxygenase. A mutation in this enzyme results in accumulation of homogentisic acid in urine. Symptoms, which present in adulthood, include arthritis, black or brown urine, and urolithiasis. Treatment includes a low-protein diet with vitamin C."
What is the definition of Hawkinsinuria?,"Hawkinsinuria (4-Hydroxyphenylpyruvate Hydroxylase Deficiency) is an autosomal dominant disease caused by a mutation in the HPD gene which codes for 4-hydroxyphenylpyruvate dioxygenase. A deficiency in this enzyme results in accumulation of hawkinsin in urine and plasma; cis-4-hydroxycyclohexylacetic acid, trans-4-hydroxycyclohexylaceid, vanillactic acid, 4-hydroxyphenylpyruvic acid, pyroglutamic acid in urine; and L-tyrosine in plasma. Symptoms include ketosis, metabolic acidosis, swimming-pool odor, and mental retardation. Treatment includes a low-protein diet and vitamin C."
What is the definition of Tyrosinemia Type I?,"Tyrosinemia type I, also known as fumarylacetoacetase or FAH deficiency, is the most severe type of tyrosinemia, a buildup of tyrosine in the body. It is caused by an autosomal recessive mutation in the the FAH gene that encodes for fumarylacetoacetase, an enzyme that is responsible for the last of five steps that are involved in the metabolic breakdown of tyrosine in the liver and kidneys. The lack of this enzyme's function leads to a buildup of 4-fumarylacetoacetic acid as it couldn't be broken down to fumaric acid and acetoacetic acid. This also leads to an increased concentration of maleylacetoacetic acid. This eventually leads to the increased concentration of L-tyrosine in the body. Symptoms of tyrosinemia type I include jaundice and an enlarged liver, kidney dysfunction, as well as a failure to grow, as foods with high protein and amino acids lead to increased symptoms. Additionally, individuals are more at risk for future liver cancer."
What is the definition of Argininemia?,"Argininemia is caused by a mutation in the gene ARG, encoding liver arginase, which hydrolyses arginine to urea and ornithine in the last step of the urea cycle. A defect in liver arginase causes accumulation of ammonia in blood; arginine, creatine, guanidinoacetate, and homoarginine in plasma; urea nitrogen in serum; arginine and homoarginine in spinal fluid; and arginiosuccinate orotic acid, and uracil in urine. Symptoms include ataxia, cerebral atrophy, chorea, jaundice, and seizures."
What is the definition of Argininosuccinic Aciduria?,"Argininosuccinic Aciduria, (Argininosuccinase Deficiency, Argininosuccinate Lyase Deficiency, ASL Deficiency) is an autosomal recessive disorder caused by a mutation in the ASL gene which codes for argininosuccinate lyase. It results in accumulation of citrulline, arginosuccinic acid, L-arginine, and L-glutamic acid in plasma as well as ammonia in blood. Infants are lethargic and unwilling to eat. They may develop seizures, coma, and failure to thrive as toxic ammonia accumulates."
What is the definition of Citrullinemia Type I?,"Citrullinemia Type I, (Argininosuccinate Synthetase Deficiency, Citrullinuria, Citrullinemia, ASS) is an autosomal recessive urea cycle disorder that causes ammonia and other toxic substances to accumulate in the blood. Two forms of citrullinemia have been described, both having different signs and symptoms, and are caused by mutations in different genes. Citrullinemia belongs to a class of genetic diseases called urea cycle disorders. The urea cycle is a sequence of chemical reactions that takes place in the liver. These reactions process excess nitrogen, generated when protein is used by the body, to make a compound called urea that is excreted by the kidneys. Citrullinemia Type I is an autosomal recessive disease caused by mutation in the ASS gene which codes for argininosuccinate synthetase. A deficiency in this enzyme results in accumulation of citruilline as well as glycine and orotic acid in urine. Infants appear normal at birth, but within the first week of life symptoms such as feeding difficulties, irritability, hypotonia, seizures, and vomiting present and eventually lead to premature death."
What is the definition of Ornithine Transcarbamylase Deficiency (OTC Deficiency)?," It is an inherited disorder which causes toxic levels of ammonia to build up in the blood.  Ornithine transcarbamylase, the defective enzyme in this disorder, is the final enzyme in the proximal portion of the urea cycle.  It is responsible for converting carbamoyl phosphate and ornithine into citrulline.  OTC deficiency is inherited in an X-linked recessive manner, meaning males are more commonly affected than females.  In severely affected individuals, ammonia concentrations increase rapidly, causing ataxia, lethargy, and death without rapid intervention.  OTC deficiency is diagnosed using a combination of clinical findings and biochemical testing, while confirmation is often done using molecular genetics techniques (Wikipedia).  . "
What is the definition of beta-Ureidopropionase Deficiency?,"Beta-ureidopropionase deficiency (Beta Alanine-Synthase Deficiency, UPB1, BUP1) is an autosomal recessive disease caused by mutations in the UPB1 gene which codes for beta-ureidopropionase. A deficiency in this enzyme results in accumulation of N-carbamyl-beta-amino acids. Symptoms include hypotonia, dystonic movements, scoliosis, microcephaly, and severe developmental delay."
What is the definition of UMP Synthase Deficiency (Orotic Aciduria)?,"Orotic Aciduria (Orotic acidemia) is caused by a defect in uridine monophosphate synthetase (UMPS) (orotate phosphoribosyl transferase and orotidine-5’-decarboxylase), an enzyme that catalyses the formation of uridine monophosphate (UMP), an energy carrying molecule in many important biosynthetic pathways. This disease is marked by very high accumulation of orotic acid in the urine, sometimes causing urinary obstruction. Symptoms include megaloblastic anemia as well as failure to thrive."
What is the definition of Dihydropyrimidinase Deficiency?,"Dihydropyrimidinase Deficiency (DHPA, Dihydropyrimidinuria Deficiency, DPH Deficiency) is an autosomal recessive disease caused by a mutation in the DPYS gene which codes for dihydropyrimidinase. A deficiency in this enzyme results in accumulation of dihydrothymine, dihydrouracil, thymine, and uracil in urine. Symptoms, which present at birth, include metabolic acidosis, difficulty feeding, and seizures."
What is the definition of MNGIE (Mitochondrial Neurogastrointestinal Encephalopathy)?,"Myoneurogastrointestinal encephalopathy, or mitochondrial neurogastrointestinal encephalopathy syndrome (MNGIE), is a multisystem disorder caused by mutations in the gene encoding thymidine phosphorylase, which normally uses thymidine and phosphate as substrates to catalyze the reaction between these two substrates to create thymine and 2-deoxy-alpha-D-ribose 1-phosphate. MNGIE causes accumulation of thymidine and deoxyuridine in the urine. Symptoms of MNGIE include ptosis, progressive external ophthalmoplegia, gastrointestinal dysmotility (often pseudoobstruction), diffuse leukoencephalopathy, peripheral neuropathy, and myopathy."
What is the definition of Carbamoyl Phosphate Synthetase Deficiency?,"Carbamoyl phosphate synthetase (CPS) deficiency (Carbamoyl phosphate synthetase I deficiency) is a urea cycle defect that results from a deficiency in an enzyme that mediates the normal path for incorporation of ammonia. Carbamoyl phosphate is derived from catabolism of amino acids into a 1-carbon compound, in which the carbon atom is derived from bicarbonate. The process is exclusively mitochondrial and requires the expenditure of two ATP molecules. Two hepatocellular enzymes exist: CPS I and CPS II. CPS I is exclusively intramitochondrial, and its deficiency is responsible for the disease. CPS I is the most plentiful single protein in hepatic mitochondria, accounting for about 20% of the matrix protein. CPS II is exclusively cytosolic and is an important enzyme in de novo synthesis of pyrimidine nucleotides. The regulation of CPS I activity depends on the levels of N -acetylglutamate.  In patients with homozygous CPS I deficiency, the ability to fix waste nitrogen is completely absent, resulting in increasing levels of free ammonia with the attendant effects on the CNS. A recent molecular and functional examination of the mutational effects showed that, although some mutations affect both substrate affinity and efficiency of the reaction, others affect one more than the other. Some mutations are associated with enhanced RNA instability, which leads to diminished protein synthesis.  The hepatic urea cycle is the major route for waste nitrogen disposal. Waste nitrogen is chiefly generated from protein and amino acid metabolism. Low-level synthesis of certain cycle intermediates in extrahepatic tissues also makes a small contribution to waste nitrogen disposal. A portion of the cycle is mitochondrial in nature; mitochondrial dysfunction may impair urea production and may result in hyperammonemia. Overall, activity of the cycle is regulated by the rate of synthesis of N -acetylglutamate, the enzyme activator of CPS I, which initiates incorporation of ammonia into the cycle."
What is the definition of Congenital Bile Acid Synthesis Defect Type II?,"Congenital Bile Acid Synthesis Defect Type II is a congenital defect in bile acid synthesis with delta(4)-3-oxosteroid 5-beta-reductase deficiency is caused by mutation in the AKR1D1 gene. 3-oxo-5-beta-steroid 4-dehydrogenase catalyzes the bile acid intermediates 7-alpha,12-alpha-dihydroxy-4-cholesten-3-one and 7-alpha-hydroxy-4-cholesten-3-one. Chenodeoxycholic acid and cholic acid are decreased in plasma and urine. Symptoms of this disease include cholestatic jaundice, atypical oxo and allo bile acids in urine and serum, liver failure, and steatosis."
What is the definition of Congenital Bile Acid Synthesis Defect Type III?,"Congenital Bile Acid Synthesis Defect Type III (CBASIII) is caused by a defect in 25-hydroxycholesterol 7-alpha-hydroxylase, which plays a role in synthesis of bile acids. The synthesis of primary bile acids from cholesterol occurs via two pathways: the classic neutral pathway involving cholesterol 7-alpha-hydroxylase (CYP7A1), and the acidic pathway involving a distinct microsomal oxysterol 7-alpha-hydroxylase (CYP7B1). CBASIII is characterized by accumulation of bile acids in the urine. Symptoms include severe cholestasis, cirrhosis, and liver failure."
What is the definition of Familial Hypercholanemia (FHCA)?,"Familial Hypercholanemia can be caused by mutations in the TJP2, BAAT or EPHX1 genes which code for bile acid-CoA:amino acid N-acyltransferase, which is involved in bile acid metabolism. In liver hepatocytes, it catalyzes the second step in the conjugation of C24 bile acids (choloneates) to glycine and taurine before excretion into bile canaliculi. The major components of bile are cholic acid and chenodeoxycholic acid. In a first step the bile acids are converted to an acyl-CoA thioester, either in peroxisomes (primary bile acids deriving from the cholesterol pathway), or cytoplasmic at the endoplasmic reticulum (secondary bile acids). May catalyze the conjugation of primary or secondary bile acids, or both. The conjugation increases the detergent properties of bile acids in the intestine, which facilitates lipid and fat-soluble vitamin absorption. In turn, bile acids are deconjugated by bacteria in the intestine and are recycled back to the liver for reconjugation (secondary bile acids). Bile acid-CoA:amino acid N-acyltransferase may also act as an acyl-CoA thioesterase that regulates intracellular levels of free fatty acids. Familial hypercholanemia is characterized by increased bile acids in plasma. Symptoms include rickets and steatorrhea."
What is the definition of Zellweger Syndrome?,"Zellweger syndrome, also known as cerebrohepatorenal syndrome, is an autosomal recessive peroxisome biogenesis disorder that is part of the family of Zellweger spectrum disorders. It is caused by a defect in one of 12 or more of the PEX genes (PEX1, 2, 3, 5, 6, 10, 12, 13, 14, 16, 19 and 26) that produce proteins called peroxins. Peroxins are used in the formation of peroxisomes, and can be involved in recognition of proteins targeted for the peroxisome, as well as their transport into the peroxisome. Peroxisomes typically break down both very long chain and branched fatty acids, but if they aren't present, these fatty acids build up in the blood and body, harming organs such as the brain and liver. Additionally, due to the fact that some processes, such as plasmalogen biosynthesis, occur in or using peroxisomes, and can lead to deficiencies in plasmalogens. These are important in brain and lung function, leading to other symptoms.Zellweger syndrome is characterized by an increase in levels of very long chain fatty acids in the blood plasma, as well as more visible physical symptoms, such as an abnormally large or small head at birth, characteristic facial features and poor muscle tone, which can lead to an inability of infants to feed. Other symptoms include an enlarged liver, skeletal abnormalities and low CNS function. Infants very rarely live longer than one year, and the only treatment is for symptoms the patient is experiencing, not for the syndrome itself."
What is the definition of Cerebrotendinous Xanthomatosis (CTX)?,"Cerebrotendinous Xanthomatosis is caused by mutation in the CYP27A1 gene, which encodes sterol 27-hydroxylase. This enzyme catalyzes the first step in the oxidation of the side chain of sterol intermediates; the 27-hydroxylation of 5-beta-cholestane-3-alpha,7-alpha,12-alpha-triol. Cerebrotendinous Xanthomatosis is a rare, inherited lipid-storage disease with large deposits of cholesterol and cholestanol are found in virtually every tissue, particularly the Achilles tendons, brain, and lungs. Symptoms include progressive neurologic dysfunction (cerebellar ataxia beginning after puberty, systemic spinal cord involvement and a pseudobulbar phase leading to death), premature atherosclerosis, and cataracts."
What is the definition of Dimethylglycine Dehydrogenase Deficiency?,"Dimethylglycine Dehydrogenase Deficiency (DMGDH deficiency; Dimethylglycinuria) phenotype in the catabolism of choline, catalyzing the oxidative demethylation of dimethylglycine (DMG) to form sarcosine. A defect in DMGDH results in the accumulation of N,N-dimethylglycine and creatinine kinase in serum, and N,N-dimethylglycine in urine. Symptoms of this disease include an unusual odor and muscle weakness."
What is the definition of Dihydropyrimidine Dehydrogenase Deficiency (DHPD)?,"Dihydropyrimidine Dehydrogenase Deficiency (DHPD; Thymine-uraciluria) is a rare autosomal recessive disorder caused by a mutation in the DPYD gene which codes for dihydropyrimidine dehydrogenase. A deficiency in this enzyme results in accumulation of 5-hydroxymethyluracil, thymine, and uracil in urine. Symptoms include nystagmus, large liver, hypotonia, growth and mental retardation, and seizures."
What is the definition of Sarcosinemia?,"Sarcosinemia (SAR), also known as hypersarcosinemia, sarcosine dehydrogenase complex deficiency, SARDH deficiency, SARDHD or SARD deficiency, is an autosomal recessive metabolic disorder leading to increased levels of the amino acid sarcosine in blood plasma, as well as increased levels of sarcosine excreted in urine. SAR can be caused by a mutation, either homozygous or compound heterozygous, in the SARDH gene which codes for the sarcosine dehydrogenase enzyme. This enzyme converts sarcosine to glycine, and its absence leads to an increase in the amount of sarcosine in the body. It can also potentially be caused by a lack of folate, as folate is used in the sarcosine dehydrogenase reaction, and even with a working enzyme, the lack of substrates can prevent the conversion from occurring, leading to the same effects. The condition has been associated with mental and motor retardation, visual impairment, however other cases have been detected with no mental or physical abnormalities other than increased sarcosine levels, so it is possible that the defect is benign, or that there exist some phenotypes that are more severe than others, or unknown disorders present in the cases showing symptoms.Sarcosine can be formed from a series of reactions starting with trimethylglycine. This, along with homocysteine, react using betaine-homocysteine S-methyltransferase to form L-methionine, as well as dimethylglycine. The dimethylglycine then enters the mitochondrial matrix, and interacts with dimethylglycine dehydrogenase along with a water molecule, forming formadehyde and sarcosine. Sarcosine can also be formed in a reversible reaction from S-adenosylmethionine and glycine, using glycine N-methyltransferase as the enzyme, and forming S-adenosylhomocysteine as another product. Normally, sarcosine can interact with sarcosine dehydrogenase in the mitochondria, forming both formaldehyde and glycine. However, in this disorder, the gene encoding sarcosine dehydrogenase has been mutated and the protein is not produced, preventing this reaction from occurring. This leads to an increased concentration of sarcosine, which leads to the effects of the condition."
What is the definition of Galactosemia?,"Galactosemia (GALT Deficiency; GALT; Galactose-1-Phosphate Uridylyltransferase Deficiency) is a rare genetic disorder caused by a mutation in the GALT gene which codes for galactose-1-phosphate uridylyltransferase. A deficiency in this enzyme results in accumulation of D-galactose and galactitol in plasma and urine; bilirubin, chloride, and galactose-1-phosphate, and transaminases in serum. Symptoms, which present at birth, include jaundice, enlarged liver, anemia, weight loss, and vomiting. Treatment includes galactose-free diet, antibiotics, and vitamin K."
What is the definition of Gaucher Disease?,"Gaucher disease is caused by a defect in the GBA gene which codes for glucosylceramidase. A defect in this enzyme results in accumulation of glucosylceramide in in brain, bone marrow, liver, spleen, lungs, and other organs. Gaucher’s disease has three common clinical subtypes. Type I (or non-neuropathic type) is the most common form of the disease. Symptoms may begin early in life or in adulthood. They include enlarged liver, grossly enlarged spleen, skeletal weakness and bone disease. Spleen enlargement and bone marrow replacement cause anemia, thrombocytopenia and leukopenia. Type II (or acute infantile neuropathic Gaucher’s disease) typically begins within 6 months of birth. Symptoms include an enlarged liver and spleen, extensive and progressive brain damage, eye movement disorders, spasticity, seizures, limb rigidity, and a poor ability to suck and swallow. Affected children usually die by age 2. Type III (the chronic neuropathic form) can begin at any time in childhood or even in adulthood. Major symptoms include an enlarged spleen and/or liver, seizures, poor coordination, skeletal irregularities, eye movement disorders, blood disorders including anemia and respiratory problems. Patients often live into their early teen years and adulthood. For type 1 and most type 3 patients, enzyme replacement treatment with intravenous recombinant glucocerebrosidase (imiglucerase) can dramatically decrease liver and spleen size, reduce skeletal abnormalities, and reverse other manifestations. Successful bone marrow transplantation cures the non-neurological manifestations of the disease. Surgery to remove the spleen (splenectomy) may be required on rare occasions if the patient is anemic or when the enlarged organ affects the patient’s comfort. Blood transfusion may benefit some anemic patients. Other patients may require joint replacement surgery to improve mobility and quality of life. Other treatment options include antibiotics for infections, antiepileptics for seizures, bisphosphonates for bone lesions, and liver transplants. Substrate reduction therapy may prove to be effective in stopping Type 2, as it can cross through the blood barrier into the brain. There is currently no effective treatment for the severe brain damage that may occur in patients with types 2 and 3 Gaucher disease."
What is the definition of Globoid Cell Leukodystrophy?,"Globoid Cell Leukodistrophy, (GLD; Krabbe disease; Galactosylceramide Lipidosis) is caused by a defect in the GALC gene which codes for Galactocerebrosidase. A defect in this enzyme results in accumulation of galactosylceramide and psychosine in central nervous system. Infants with Krabbe disease are normal at birth. Symptoms begin between the ages of 3 and 6 months with irritability, fevers, limb stiffness, seizures, feeding difficulties, vomiting, and slowing of mental and motor development. Other symptoms include muscle weakness, spasticity, deafness, optic atrophy and blindness, paralysis, and difficulty when swallowing. Prolonged weight loss may also occur. There are also juvenile- and adult-onset cases of Krabbe disease, which have similar symptoms but slower progression. In infants, the disease is generally fatal before age 2. Patients with late-onset Krabbe disease tend to have a slower progression of the disease and live significantly longer. Although there is no cure for Krabbe disease, bone marrow transplantation has been shown to benefit cases early in the course of the disease."
What is the definition of Metachromatic Leukodystrophy (MLD)?,"Metachromatic leukodystrophy (MLD) is caused by a defect in the ARSA gene which does for arylsulfatase A. A defect in this enzyme results in accumulation of 3-O-sulfogalactosylceramide in urine, neural and non neural tisues like kidney and gallbladder. There are several forms of MLD. In the late infantile form, which is the most common form MLD, affected children begin having difficulty walking after the first year of life. Symptoms include muscle wasting and weakness, muscle rigidity, developmental delays, progressive loss of vision leading to blindness, convulsions, impaired swallowing, paralysis, and dementia. Children may become comatose. Untreated, most children with this form of MLD die by age 5, often much sooner. Children with the juvenile form of MLD (onset between 3–10 years of age) usually begin with impaired school performance, mental deterioration, and dementia and then develop symptoms similar to the late infantile form but with slower progression. Age of death is variable, but normally within 10 to 15 years of symptom onset. The adult form commonly begins after age 16 as a psychiatric disorder or progressive dementia. Adult-onset MLD progresses more slowly than the late infantile and juvenile forms, with a protracted course of a decade or more."
What is the definition of Glycerol Kinase Deficiency?,"Glycerol Kinase Deficiency (Hyperglycerolemia; Glyceroluria; GK Deficiency; GKD) is a rare metabolic disease caused by a deficiency in the GK gene which codes for glycerol kinase. A deficiency in this enzyme results in accumulation of glycerol in urine and serum. Symptoms include cryptorchism, trabismus, myopathy, lethargy, and vomiting. Treatment includes corticosteroids and acute glucose infusion."
What is the definition of Glycogen Storage Disease Type 1A (GSD1A) or Von Gierke Disease?,"Glycogen storage disease type 1A (GSD1A), or von Gierke disease, is caused by a defect in the G6PC gene which codes for Glucose-6-phosphatase. Glucose-6-phosphatase hydrolyzes glucose-6-phosphate to glucose and is responsible for the regulation of blood glucose level. A defect in this enzyme results in accumulation of glycogen in affected tissues, like liver and kidney; decreased glucose level; and accumulation of lactate. Glycogen storage disease type 1A causes clinically significant end-organ disease with significant morbidity. Usually it presents in childhood. Symptoms include seizures, irritability, pallor, hypotonia, tremors, loss of consciousness, apnea and hepatomegaly. There is no cure for glycogen storage disease type 1A. Diet therapy can help to prevent hypoglycemia and reduce the symptoms. Liver transplantation may be indicated in cases of hepatic malignancy."
What is the definition of Lactose Intolerance?,"Lactose Intolerance (Hypolactasia, Adult type; Adult Lactase Deficiency; Disaccaride Intolerance III; Lactase Persistence, Included) is caused by a deceased expression of intestinal lactase, an enzyme expressed in newborns.  Its activity declines following weaning.  Lactase deficiency is present in up to 80 percent of blacks and Latinos, and up to 100 percent of American Indians and Asians.  Persons with lactose intolerance are unable to digest significant amounts of lactose.  Due to the reduced lactase level, lactose present in dairy products cannot be digested in the small intestine and instead are fermented by intestinal bacteria.  Common symptoms include abdominal pain and bloating, excessive flatus, and watery stool following the ingestion of foods containing lactose.  Excess lactose may be present in the urine. "
What is the definition of Malonic Aciduria?,"Malonic Aciduria, is an autosomal recessive metabolic disorder caused by a genetic mutation which disrupts the activity of Malonyl-Coa decarboxylase. This enzyme breaks down Malonyl-CoA (a fatty acid precursor and a fatty acid oxidation blocker) into Acetyl-CoA and carbon dioxide. A defect in Malonyl-CoA decarboxylase results in accumulation of ammonia in the blood; methylmalonic acid in the plasma; creatinine in the serum; 3-Aminoisobutyric acid, 3 Hydroxypropionic acid, 3 hydoxyvaleric acid, glycine, acylcrnitine and methylmalonic acid in the urine; and methylmalonic acid in the spinal fluid. Symptoms include cardiomyopathy, growth retardation, ketosis, nephrosis, pancreatitis, respiratory distress, and neutropenia."
What is the definition of Methylmalonic Aciduria Due to Cobalamin-Related Disorders?,"Methylcobalamin (MeCbl) is the cofactor of methionine synthase and involved in the conversion of homocysteine to methionine. Adenosylcobalamin (AdoCbl) is a cofactor for methylmalonyl CoA mutase converting methylmalonic acid into succinic acid. Methylmalonyl-CoA mutase is involved in key metabolic pathways, catalyzing the isomerization of methylmalonyl-CoA to succinyl-CoA. It requires its Vitamin B12 derived prosthetic group, adenosylcobalamin, to function.It catalyzes the isomerization of methylmalonyl-CoA to succinyl-CoA. It requires its Vitamin B12 derived prosthetic group, adenosylcobalamin, to function. Defects in these cofactors for methylmalonyl CoA mutase cause accumulation of ammonia in blood; methylmalonic acid in plasma; creatinine and uric acid in serum; 3-Aminoisobutyric acid, 3-Hydroxypropionic acid, 3-Hydroxyvaleric acid, glycine, methylcitric acid and methylmalonic acid in urine; and methylmalonic acid in spinal fluid. Symptoms include anemia, dehydration, growth retardation, nephrosis, respiratory distress and metabolic acidosis."
What is the definition of Non-Ketotic Hyperglycinemia?,"Non Ketotic Hyperglycinemeia (Glycine encephalopathy; Glycine cleavage system deficiency; NKH) is caused by mutations in several genes in the mitochondrial glycine cleavage system. These include the genes encoding P protein (GLDC), T protein (GCST), and, in one case, the H protein (GCSH). Most patients with GCE (Glycine Encephalopathy, or NKH) have a defect in the GLDC gene.The enzyme system for cleavage of glycine (glycine cleavage system), which is confined to the mitochondria, is composed of 4 protein components: P protein (a pyridoxal phosphate-dependent glycine decarboxylase), H protein (a lipoic acid-containing protein), T protein (a tetrahydrofolate-requiring enzyme), and L protein (a lipoamide dehydrogenase). NKH is characterized by accumulation of glycine in plasma, spinal fluid and urine. Symptoms include seizures, respiratory distress, mental retardation, chorea, visual impairment and hydrocephalus."
What is the definition of Vitamin A Deficiency?,"Vitamin A deficiency can be caused by many causes. A defect in the BCMO1 gene which codes for beta,beta-carotene 15,15’-monooxygenase is one of them. Beta,beta-carotene 15,15’-monooxygenase catalyzes the chemical reaction where the two substrates are beta-carotene and O2, whereas its product is retinal. A defect in this enzyme results in decrease of levels of retinal and vitamin A in serum; Signs and symptoms include night blindness, poor adaptation to darkness, dry skin and hair."
What is the definition of Hereditary Coproporphyria (HCP)?,"Hereditary coproporphyria (HCP) is caused by a defect in the CPOX gene which codes for mitochondrial coproporphyrinogen-III oxidase. A defect in this enzyme results in accumulation of the porphyrin precursors porphobilinogen and 5-aminolevulinic acid; increase of fecal and urinary excreation of coproporphyrins. Symtpoms include reddish-purple urine, acute neurological problems (typically episodic confusion and sensory changes), and attacks of acute abdominal/nerve pain. Around 30% suffer photosensitive skin eruptions with nail involvement; these can lead to permanent scarring. While there is no cure for this condition, there are preventative measures people can take to regulate symptoms. A diet high in carbohydrates, glucose, as well as avoidance of aggravating factors (such as alcohol and drug use) can prevent attacks."
What is the definition of 2-Hydroxyglutric Aciduria (D and L Form)?,"L-2-Hydroxyglutaric Aciduria (D-2-Hydroxyglutaric Aciduria ) is an autosomal recessive disease caused by a mutation in the L2HGDH gene which codes for L-2-Hydroxygluarate dehydrogenase. A deficiency in this enzyme results in accumulation of L-2-Hydroxyglutaric acid in plasma, spinal fluid, and urine; and L-lysine in plasma and spinal fluid. Symptoms, which present at birth, include ataxia, hypotonia, mental retardation, and seizures. Premature death often results.  D-2-Hydroxyglutaric Aciduria is an autosomal recessive disease caused by a mutation in the D2HGDH gene which does for D-2-Hydroxygluarate dehydrogenase. A deficiency in this enzyme results in accumulation of D-2-Hydroxyglutaric acid in plasma, spinal fluid, and urine; oxoglutaric acid in urine; and gabba-aminobutyric acid in spinal fluid. Symptoms, which present at birth, include ataxia, hypotonia, mental retardation, and seizures. Premature death often results."
What is the definition of 3-Methylglutaconic Aciduria Type IV?,"3-Methylglutaconic Aciduria Type IV (MGA, Type IV; MGA4) is an autosomal recessive disease caused by a mutation in an unknown gene. This disease results in an accumulation of cis and trans 3-methylglutaconic acid. Symptoms include, anemia, hyperammonemia, mental retardation, optic atrophy, hypotonia and early death."
What is the definition of Tay-Sachs Disease?,"Tay-Sachs Disease (TSD; GM2-Gangliosidosis, type I; B-Variant GM2-Gangliosidosis; Hexosaminidase A Deficiency; HEXA Deficiency; Tay-Sachs Disease Variant B1), is an autosomal recessive lysosomal storage disease. TSD is caused by a mutation in the alpha subunit of the hexosaminidase A gene (HEXA), which codes for the enzyme hexosaminidase A. HEXA degrades GM2 gangliosides and other molecules with terminal N-acetyl hexosamines in the brain and other tissues. A defect in this enzyme causes accumulation of oligosaccharides in urine. The most lethal variant of this disease is the classical infantile Tay-Sachs disease, in which children exhibit developmental retardation, dementia and blindness, finally ending in death by the second or third years. Tay-Sachs disease also has debilitating juvenile and adult forms. The majority of cases of TSD are found among (but not limited to) the Ashkenazi Jews and French Canadians in Eastern Quebec. Symptoms include ataxia, visual impairment and loss, cherry-red spot on retinal macula, dystosis multiplex, mental retardation, myoclonus, encephalopathy and psychosis."
What is the definition of Glucose Transporter Defect (SGLT2)?,"SGLT2 is a sodium/glucose co-transporter that exists almost exclusively in kidney tissue. It is responsible for approximately 90% of the kidney's reabsorption of glucose, and can be found in the S1 segment of the proximal convoluted tubule of the nephron. A defect in the SLC5A2 gene that codes for SGLT2 results in glucosuria, due to the inability of most of the glucose to be reabsorbed by the kidney. There are some drugs that inhibit SGLT2 and are used to decrease blood sugar in patients with type 2 diabetes mellitus."
What is the definition of Hartnup Disorder?,"Hartunup Disorder (HND, Hartnup Disease) is an autosomal recessive disease caused by a mutation in the SLC6A19 which codes for sodium-dependent neutral amino acid transporter B(0). A deficiency in this enzyme results in accumulation of L-alanine, L-asparagine, L-histidine, indoleacetic acid, L-isoleucine, L-leucine, L-phenylalanine, L-serine, L-threonine, L-tryptophan, L-valine, and L-tyrosine in urine. Symptoms include pellagra, psychosis, ataxia, and mental retardation. Treatment includes nicotinamide."
What is the definition of Iminoglycinuria?,"Iminoglycinuria, sometimes called familial iminoglycinuria, is an autosomal recessive disorder of renal tubular transport affecting reabsorption of the amino acid glycine, and the imino acids proline and hydroxyproline, leading to accumulation of these three acids in the urine. Iminoglycinuria is a rare and complex disorder, associated with a number of genetic mutations which cause defects in both renal and intestinal transport systems of glycine and imino acids. Symptoms include urolithiasis, excessive imino acids in the urine, and mental retardation."
What is the definition of Lysinuric Protein Intolerance?,"Lysinuric protein intolerance (Hyperdibasic aminoaciduria II; Dibasic aminoaciduria II; Hyperdibasic aminoaciduria II; LPI), also called hyperdibasic aminoaciduria type 2 or familial protein intolerance, is an autosomal recessive metabolic disorder affecting amino acid transport. LPI is caused by a defect in SLC7A7, Solute carrier family 7, a cationic amino acid transporter. A defect in this enzyme results in accumulation of ammmonia and reticulocytes in blood; glutamine in plasma, carnitine and ferritin in serum, and arginine, lysine and ornithine in urine. Symptoms include bone marrow abnormality, growth retardation, hyperammoniemia, mental retardation, pancreatitis, and seizures."
What is the definition of Hypercholesterolemia?,"Hypercholesterolemia literally means high blood cholesterol. The elevated cholesterol in the blood is due to abnormalities in the levels of lipoproteins, the LDL particles that carry cholesterol in the bloodstream. This disease can usually be attributed to one’s diet, genetic factors (such as LDL receptor mutations), and the presence of other disease such as diabetes or an underactive thyroid. Metabolism of cholesterol when the patient is affected by hypercholesterolemia: the deficient enzymes are actually transport proteins that transport LDL particles into the liver, and cholesterol accumulates in the bloodstream and other tissues."
What is the definition of Neuron Function?,"Neurons are electrically excitable cells that process and transmit information through electrical and chemical signals. A neuron consists of a cell body, branched dendrites to receive sensory information, and a long singular axon to transmit motor information. Signals travel from the axon of one neuron to the dendrite of another via a synapse. Neurons maintain a voltage gradient across their membrane using metabolically driven ion pumps and ion channels for charge-carrying ions, including sodium (Na+), potassium (K+), chloride (Cl−), and calcium (Ca2+).  The resting membrane potential (charge) of a neuron is about -70 mV because there is an accumulation of more sodium ions outside the neuron compared to the number of potassium ions inside.  If the membrane potential changes by a large enough amount, an electrochemical pulse called an action potential is generated. Stimuli such as pressure, stretch, and chemical transmitters can activate a neuron by causing specific ion-channels to open, changing the membrane potential. During this period, called depolarization, the sodium channels open to allow sodium to rush into the cell which results in the membrane potential to increase.  Once the interior of the neuron becomes more positively charged, the sodium channels close and the potassium channels open to allow potassium to move out of the cell to try and restore the resting membrane potential (this stage is called repolarization).  There is a period of hyperpolarization after this step because the potassium channels are slow to close, thus allowing more potassium outside the cell than necessary. The resting potential is restored after the sodium-potassium pump works to exchange three sodium ions out per two potassium ions in across the plasma membrane.  The action potential travels along the axon and upon reaching the end, causes neurotransmitters such as serotonin, dopamine, or norepinephrine to be released into the synapse. These neurotransmitters diffuse across the synapse and bind to receptors on the target cell, thus propagating the signal."
What is the definition of Benazepril Action Pathway?,"Benazepril, brand name Lotensin, belongs to the class of drugs known as angiotensin-converting enzyme (ACE) inhibitors and is used primarily to lower high blood pressure (hypertension). This drug can also be used in the treatment of congestive heart failure and type II diabetes. Benazepril is a prodrug which, following oral administration, undergoes biotransformation in vivo into its active form benazeprilat via cleavage of its ester group by the liver. Angiotensin-converting enzyme (ACE) is a component of the body's renin–angiotensin–aldosterone system (RAAS) and cleaves inactive angiotensin I into the active vasoconstrictor angiotensin II. ACE (or kininase II) also degrades the potent vasodilator bradykinin. Consequently, ACE inhibitors decrease angiotensin II concentrations and increase bradykinin concentrations resulting in blood vessel dilation and thereby lowering blood pressure."
What is the definition of Bevacizumab Action Pathway?,"Bevacizumab is a humanized anti-VEGF monoclonal antibody used in the treatment of cancer. Cancer cells tend to overexpress VEGF, which stimulates angiogenesis, facilitating cancer growth and metastasis. The majority of VEGF’s effects are mediated through its binding to the VEGFR-2 receptor on endothelial cell surfaces. Upon binding, the receptor autophosphorylates and initiates a signalling cascade, starting with the activation of CSK. CSK phosphorylates Raf-1, which subsequently phosphorylates MAP kinase kinase, which phosphorylates MAP kinase. The activated MAP kinase enters the nucleus and stimulates the expression of angiogenic factors resulting in increased cell proliferation, migration,  permeability, invasion, and survival.Binding of VEGF to VEGFR-2 also activates phospholipase C PIP2 into DAG and IP3. DAG may be involved in the activation of Raf-1 leading to angiogenesis, while IP3 activates PI3K and triggers calcium release from the endoplasmic reticulum. This ultimately leads to the activation of nitric oxide synthase and the production of nitric oxide, which stimulates vasodilation and increases vascular permeability. In cancer, VEGF has also been shown to bind to the VEGFR-1 receptor. However, its effects on angiogenesis are unclear at the moment. There are some evidence to show that VEGFR-1 may cross-talk with VEGFR-2 and initiate the signalling cascades described above.Bevacizumab exerts its effect by binding to extracellular VEGF and preventing its binding to receptors on the endothelial cell surfaces. This in turns inhibits the MAP and IP3  and supresses angiogenesis."
What is the definition of Vatalanib Action Pathway?,"Vatalanib is an anti-VEGFR molecule in the treatment of cancer. Cancer cells tend to overexpress VEGF, which stimulates angiogenesis, facilitating cancer growth and metastasis. The majority of VEGF’s effects are mediated through its binding to the VEGFR-2 receptor on endothelial cell surfaces. Upon binding, the receptor autophosphorylates and initiates a signalling cascade, starting with the activation of CSK. CSK phosphorylates Raf-1, which subsequently phosphorylates MAP kinase kinase, which phosphorylates MAP kinase. The activated MAP kinase enters the nucleus and stimulates the expression of angiogenic factors resulting in increased cell proliferation, migration,  permeability, invasion, and survival.Binding of VEGF to VEGFR-2 also activates phospholipase C PIP2 into DAG and IP3. DAG may be involved in the activation of Raf-1 leading to angiogenesis, while IP3 activates PI3K and triggers calcium release from the endoplasmic reticulum. This ultimately leads to the activation of nitric oxide synthase and the production of nitric oxide, which stimulates vasodilation and increases vascular permeability. In cancer, VEGF has also been shown to bind to the VEGFR-1 receptor. However, its effects on angiogenesis are unclear at the moment. There are some evidence to show that VEGFR-1 may cross-talk with VEGFR-2 and initiate the signalling cascades described above.Vatalanib exerts its effect by binding to intracellular tyrosine kinase domain of VEGFR-2 and preventing receptor autophosphorylation and activation of downstream pathways, resulting in suppression of angiogenesis."
What is the definition of Irinotecan Action Pathway?,"Irinotecan is a topoisomerase I inhibitor used in the treatment of cancer. It is hydrolyzed by esterases in the liver, intestine, and cytoplasm into the active metabolite SN-38, which binds to and inhibits the function of topoisomerase I. Topoisomerase I unwinds DNA by making transient single strand breaks that relieves the torsion of supercoiled DNA. In the unwound form, DNA can serve as a template for DNA replication as well as transcription. In the normal state, this effect is transient and the breaks DNA are quickly religated by topoisomerase I itself. SN-38 binding, however, inhibits religation and stabilizes the DNA-topoisomerase I complex in the cleaved DNA form, ultimately leading to breaks in both DNA chains and cell death."
What is the definition of Paclitaxel Action Pathway?,"Paclitaxel is an anticancer agent isolated from the bark of the yew tree. It is classified as a microtubule-stabilizing agent and exerts cell killing effects by disrupting mitosis in dividing cells. Microtubules are made up of α- and β- tubulin heterodimers arranged head to tail and assembled to form a cylinder. Microtubules possess complex polymerization dynamics that are essential for movement of chromosomes and proper segregation of daughter cells during mitosis. Paclitaxel binds directly to the inner surface of β-subunits along the length of microtubules. Binding is thought to induce a conformational change in tubulin that increases its affinity for neighbouring molecules. At sufficiently high concentrations, paclitaxel can bind to β-tubulin in a one to one ratio and stimulate microtubule polymerization. At lower clinically relevant drug concentrations, paclitaxel stabilizes microtubules and prohibits further polymerization and depolymerization. Suppression of microtubule dynamics may prevent chromosomes from moving from the spindle poles to the metaphase plate slowing or preventing progression from metaphase to anaphase. Cells enter a state of mitotic arrest from which they may progress to one of several fates. The tetraploid cell may undergo unequal cell division producing aneuploid daughter cells. Alternatively, it may exit the cell cycle without undergoing cell division, a process termed mitotic slippage or adaptation. These cells may continue progressing through the cell cycle as tetraploid cells (Adaptation I), may exit G1 phase and undergo apoptosis or senescence (Adaption II), or may escape to G1 and undergo apoptosis during interphase (Adaptation III). Another possibility is cell death during mitotic arrest. Alternatively, mitotic catastrophe may occur causing cell death. Paclitaxel is susceptible to cellular drug resistance caused by drug efflux via a number of multidrug resistance-associated proteins."
What is the definition of Docetaxel Action Pathway?,"Docetaxel, a semisynthetic analogue of paclitaxel, is an anticancer agent classified as a microtubule-stabilizing agent. Similar to paclitaxel, it exerts cell killing effects by disrupting mitosis in dividing cells. Microtubules are made up of α- and β- tubulin heterodimers arranged head to tail and assembled to form a cylinder. Microtubules possess complex polymerization dynamics that are essential for movement of chromosomes and proper segregation of daughter cells during mitosis. Docetaxel binds directly to the inner surface of β-subunits along the length of microtubules. Binding is thought to induce a conformational change in tubulin that increases its affinity for neighbouring molecules. At sufficiently high concentrations, docetaxel can bind to β-tubulin in a one to one ratio and stimulate microtubule polymerization. At lower clinically relevant drug concentrations, docetaxel stabilizes microtubules and prohibits further polymerization and depolymerization. Suppression of microtubule dynamics may prevent chromosomes from moving from the spindle poles to the metaphase plate slowing or preventing progression from metaphase to anaphase. Cells enter a state of mitotic arrest from which they may progress to one of several fates. The tetraploid cell may undergo unequal cell division producing aneuploid daughter cells. Alternatively, it may exit the cell cycle without undergoing cell division, a process termed mitotic slippage or adaptation. These cells may continue progressing through the cell cycle as tetraploid cells (Adaptation I), may exit G1 phase and undergo apoptosis or senescence (Adaption II), or may escape to G1 and undergo apoptosis during interphase (Adaptation III). Another possibility is cell death during mitotic arrest. Alternatively, mitotic catastrophe may occur causing cell death. Docetaxel is susceptible to cellular drug resistance caused by drug efflux via a number of multidrug resistance-associated proteins."
What is the definition of Vinblastine Action Pathway?,"Vinblastine (also named Velban) is a natural alkaloid isolated from the leaves of the Catharanthus roseus (commonly known as the Madagascar periwinkle). Vinblastine are used as chemotherapy medication such as an antimitotic anticancer agent. The mechanism of vinblastine is the inhibition of microtubule dynamics that would cause mitotic arrest and eventual cell death. As a microtubule destabilizing agent, Vinblastine stimulates mitotic spindle destruction and microtubule depolymerization at high concentrations. At lower clinically relevant concentrations, vinblastine can block mitotic progression. Unlike the taxanes, which bind poorly to soluble tubulin, vinblastine can bind both soluble and microtubule-associated tubulin. To be able stabilizing the kinetics of microtule, vinblastine rapidly and reversibly bind to soluble tubulin which can increase the affinity of tublin by the induction of conformational changes of tubulin. Vinblastine binds to β-tubulin subunits at the positive end of microtubules at a region called the _Vinca_-binding domain. Binding between vinblastine and solubale tubulin decreases the rate of microtubule dynamics (lengthening and shortening) and increases the duration of attenuated state of microtubules. Therefore, the proper assembly of the mitotic spindle could be prevented; and the tension at the kinetochores of the chromosomes could be reduced. Subsequently, chromosomes can not progress to the spindle equator at the spindle poles. Progression from metaphase to anaphase is blocked and cells enter a state of mitotic arrest. The cells may then undergo one of several fates. The tetraploid cell may undergo unequal cell division producing aneuploid daughter cells. Alternatively, it may exit the cell cycle without undergoing cell division, a process termed mitotic slippage or adaptation. These cells may continue progressing through the cell cycle as tetraploid cells (Adaptation I), may exit G1 phase and undergo apoptosis or senescence (Adaption II), or may escape to G1 and undergo apoptosis during interphase (Adaptation III). Another possibility is cell death during mitotic arrest. Alternatively, mitotic catastrophe may occur and cause cell death. Vinca alkaloids are also thought to increase apoptosis by increasing concentrations of p53 (cellular tumor antigen p53) and p21 (cyclin-dependent kinase inhibitor 1) and by inhibiting Bcl-2 activity. Increasing concentrations of p53 and p21 lead to changes in protein kinase activity. Phosphorylation of Bcl-2 subsequently inhibits the formation Bcl-2-BAX heterodimers. This results in decreased anti-apoptotic activity. One way in which cells have developed resistance against the vinca alkaloids is by drug efflux. Drug efflux is mediated by a number of multidrug resistant transporters as depicted in this pathway."
What is the definition of Vincristine Action Pathway?,"Vincristine (also named leurocristine) is a natural alkaloid isolated from the leaves of the Catharanthus roseus (commonly known as the Madagascar periwinkle). Vincristine are used as chemotherapy medication such as an antimitotic anticancer agent. The mechanism of vincristine is the inhibition of microtubule dynamics that would cause mitotic arrest and eventual cell death. As a microtubule destabilizing agent, Vincristine stimulates mitotic spindle destruction and microtubule depolymerization at high concentrations. At lower clinically relevant concentrations, vincristine can block mitotic progression. Unlike the taxanes, which bind poorly to soluble tubulin, vincristine can bind both soluble and microtubule-associated tubulin. To be able stabilizing the kinetics of microtule, vincristine rapidly and reversibly bind to soluble tubulin which can increase the affinity of tublin by the induction of conformational changes of tubulin. Vincristine binds to β-tubulin subunits at the positive end of microtubules at a region called the _Vinca_-binding domain. Binding between vincristine and solubale tubulin decreases the rate of microtubule dynamics (lengthening and shortening) and increases the duration of attenuated state of microtubules. Therefore, the proper assembly of the mitotic spindle could be prevented; and the tension at the kinetochores of the chromosomes could be reduced. Subsequently, chromosomes can not progress to the spindle equator at the spindle poles. Progression from metaphase to anaphase is blocked and cells enter a state of mitotic arrest. The cells may then undergo one of several fates. The tetraploid cell may undergo unequal cell division producing aneuploid daughter cells. Alternatively, it may exit the cell cycle without undergoing cell division, a process termed mitotic slippage or adaptation. These cells may continue progressing through the cell cycle as tetraploid cells (Adaptation I), may exit G1 phase and undergo apoptosis or senescence (Adaption II), or may escape to G1 and undergo apoptosis during interphase (Adaptation III). Another possibility is cell death during mitotic arrest. Alternatively, mitotic catastrophe may occur and cause cell death. Vinca alkaloids are also thought to increase apoptosis by increasing concentrations of p53 (cellular tumor antigen p53) and p21 (cyclin-dependent kinase inhibitor 1) and by inhibiting Bcl-2 activity. Increasing concentrations of p53 and p21 lead to changes in protein kinase activity. Phosphorylation of Bcl-2 subsequently inhibits the formation Bcl-2-BAX heterodimers. This results in decreased anti-apoptotic activity. One way in which cells have developed resistance against the vinca alkaloids is by drug efflux. Drug efflux is mediated by a number of multidrug resistant transporters as depicted in this pathway."
What is the definition of Vindesine Action Pathway?,"Vindesine (also named Eldesine) is a semisynthetic vinca alkaloid. Vindesine are used as chemotherapy medication such as an antimitotic anticancer agent. The mechanism of vindesine is the inhibition of microtubule dynamics that would cause mitotic arrest and eventual cell death. As a microtubule destabilizing agent, vindesine stimulates mitotic spindle destruction and microtubule depolymerization at high concentrations. At lower clinically relevant concentrations, vindesine can block mitotic progression. Unlike the taxanes, which bind poorly to soluble tubulin, vindesine can bind both soluble and microtubule-associated tubulin. To be able stabilizing the kinetics of microtule, vindesine rapidly and reversibly bind to soluble tubulin which can increase the affinity of tublin by the induction of conformational changes of tubulin. Vindesine binds to β-tubulin subunits at the positive end of microtubules at a region called the _Vinca_-binding domain. Binding between vindesine and solubale tubulin decreases the rate of microtubule dynamics (lengthening and shortening) and increases the duration of attenuated state of microtubules. Therefore, the proper assembly of the mitotic spindle could be prevented; and the tension at the kinetochores of the chromosomes could be reduced. Subsequently, chromosomes can not progress to the spindle equator at the spindle poles. Progression from metaphase to anaphase is blocked and cells enter a state of mitotic arrest. The cells may then undergo one of several fates. The tetraploid cell may undergo unequal cell division producing aneuploid daughter cells. Alternatively, it may exit the cell cycle without undergoing cell division, a process termed mitotic slippage or adaptation. These cells may continue progressing through the cell cycle as tetraploid cells (Adaptation I), may exit G1 phase and undergo apoptosis or senescence (Adaption II), or may escape to G1 and undergo apoptosis during interphase (Adaptation III). Another possibility is cell death during mitotic arrest. Alternatively, mitotic catastrophe may occur and cause cell death. Vinca alkaloids are also thought to increase apoptosis by increasing concentrations of p53 (cellular tumor antigen p53) and p21 (cyclin-dependent kinase inhibitor 1) and by inhibiting Bcl-2 activity. Increasing concentrations of p53 and p21 lead to changes in protein kinase activity. Phosphorylation of Bcl-2 subsequently inhibits the formation Bcl-2-BAX heterodimers. This results in decreased anti-apoptotic activity. One way in which cells have developed resistance against the vinca alkaloids is by drug efflux. Drug efflux is mediated by a number of multidrug resistant transporters as depicted in this pathway."
What is the definition of Vinorelbine Action Pathway?,"Vinorelbine (also named Navelbine) is a semisynthetic vinca alkaloid. Vinorelbine are used as chemotherapy medication such as an antimitotic anticancer agent. The mechanism of vinorelbine is the inhibition of microtubule dynamics that would cause mitotic arrest and eventual cell death. As a microtubule destabilizing agent, vinorelbine stimulates mitotic spindle destruction and microtubule depolymerization at high concentrations. At lower clinically relevant concentrations, vinorelbine can block mitotic progression. Unlike the taxanes, which bind poorly to soluble tubulin, vinorelbine can bind both soluble and microtubule-associated tubulin. To be able stabilizing the kinetics of microtule, vinorelbine rapidly and reversibly bind to soluble tubulin which can increase the affinity of tublin by the induction of conformational changes of tubulin. Vinorelbine binds to β-tubulin subunits at the positive end of microtubules at a region called the _Vinca_-binding domain. Binding between vinorelbine and solubale tubulin decreases the rate of microtubule dynamics (lengthening and shortening) and increases the duration of attenuated state of microtubules. Therefore, the proper assembly of the mitotic spindle could be prevented; and the tension at the kinetochores of the chromosomes could be reduced. Subsequently, chromosomes can not progress to the spindle equator at the spindle poles. Progression from metaphase to anaphase is blocked and cells enter a state of mitotic arrest. The cells may then undergo one of several fates. The tetraploid cell may undergo unequal cell division producing aneuploid daughter cells. Alternatively, it may exit the cell cycle without undergoing cell division, a process termed mitotic slippage or adaptation. These cells may continue progressing through the cell cycle as tetraploid cells (Adaptation I), may exit G1 phase and undergo apoptosis or senescence (Adaption II), or may escape to G1 and undergo apoptosis during interphase (Adaptation III). Another possibility is cell death during mitotic arrest. Alternatively, mitotic catastrophe may occur and cause cell death. Vinca alkaloids are also thought to increase apoptosis by increasing concentrations of p53 (cellular tumor antigen p53) and p21 (cyclin-dependent kinase inhibitor 1) and by inhibiting Bcl-2 activity. Increasing concentrations of p53 and p21 lead to changes in protein kinase activity. Phosphorylation of Bcl-2 subsequently inhibits the formation Bcl-2-BAX heterodimers. This results in decreased anti-apoptotic activity. One way in which cells have developed resistance against the vinca alkaloids is by drug efflux. Drug efflux is mediated by a number of multidrug resistant transporters as depicted in this pathway."
What is the definition of Etoposide Action Pathway?,"Etoposide is an podophyllotoxin derative that is used in the treatment of certain cancers. It inhibits mitosis and induces cell death by acting as a topoisomerase II poison. Topoisomerase II is an enzyme in the nucleus of cells that unwinds DNA by making transient double-stranded breaks, relieving the torsion of supercoiled DNA. In the unwound form, DNA can serve as a template for DNA replication as well as transcription. In the normal state, this effect is transient and the breaks DNA are quickly religated by topoisomerase II itself. Etoposide, however, inhibits religation and stabilizes the DNA-topoisomerase II complex in the cleaved DNA form, ultimately leading to breaks in both DNA chains and cell death.Etoposide is also converted into catechol and o-quinone derivatives in the liver and in lysosomes respectively. These metabolites are highly oxidative and can directly damage DNA, which may also contribute to the drug’s cytotoxic effects."
What is the definition of Teniposide Action Pathway?,"Teniposide is an podophyllotoxin derative that is used in the treatment of certain cancers. It inhibits mitosis and induces cell death by acting as a topoisomerase II poison. Topoisomerase II is an enzyme in the nucleus of cells that unwinds DNA by making transient double strand breaks, relieving the torsion of supercoiled DNA. In the unwound form, DNA can serve as a template for DNA replication as well as transcription. In the normal state, this effect is transient and the breaks DNA are quickly religated by topoisomerase II itself. Teniposide, however, inhibits religation and stabilizes the DNA-topoisomerase II complex in the cleaved DNA form, ultimately leading to breaks in both DNA chains and cell death.Teniposide is also converted into catechol and o-quinone derivatives in the liver and in lysosomes respectively. These metabolites are highly oxidative and can directly damage DNA, which may also contribute to the drug’s cytotoxic effects."
What is the definition of Gemcitabine Action Pathway?,"Gemcitabine is a cytidine analogue used in the treatment of certain cancers. Gemcitabine enters the cell via sodium nucleoside co-transporters (SLC29A1, SLC28A1, and SLC28A3), where it acts through multiple mechanisms to produce a cytotoxic effect. Gemcitabine is phosphorylated into gemcitabine monophosphate by deoxycytidine kinase, which is then subsequently phosphorylated into the diphosphate and triphosphate nucleotides by UMP-CMP kinase and nucleoside diphosphate kinase respectively. Gemcitabine diphosphate inhibits ribonucleoside-diphosphate reductase, a crucial enzyme in the conversion of ribonucleotides into deoxyribonucleotides for DNA synthesis. Gemcitabine triphosphate on the other hand can be incorporated into DNA, causing chain termination. Furthermore, gemcitabine monophosphate can be deaminated into difluoro-deoxyuridine monophosphate, which inhibits thymidylate synthase, an enzyme involved in the production of dTTP for DNA synthesis."
What is the definition of Cyclophosphamide Action Pathway?,"Cyclophosphamide is an alkylating agent used in the treatment of certain cancers. Following absorption, cyclophosphamide is converted into 4-hydroxyphosphamide by a variety of cytochrome P450 isozymes in the liver. 4-Hydroxyphosphamide is more soluble than cyclophosphamide and is the primary form of the drug that is transported in blood. 4-Hydroxyphosphamide crosses the plasma membrane of the cancer cell and spontaneuosly forms aldophosphamide. This is a reversible reaction. Aldophosphamide can decompose into acrolein and phosphoramide mustard. Phosphoramide mustard is the active alkylating agent and forms alkyl adducts with DNA through a phosphoramide aziridinium intermediate. Alkylation of DNA causes DNA damage and eventually cell death."
What is the definition of Ifosfamide Action Pathway?,"Ifosfamide is an alkylating agent used in the treatment of certain cancers. Following absorption, ifosfamide is converted into 4-hydroxyifosfamide by a variety of cytochrome P450 isozymes in the liver. 4-Hydroxyifosfamide crosses the plasma membrane of the cancer cell and spontaneuosly forms aldoifosfamide. This is a reversible reaction. Aldoifosfamide can decompose into acrolein and ifosforamide mustard. Ifosforamide mustard is the active alkylating agent and forms alkyl adducts with DNA through an ifosforamide aziridinium intermediate. Alkylation of DNA causes DNA damage and ultimately cell death."
What is the definition of Tamoxifen Action Pathway?,"Tamoxifen is a selective estrogen modulator (SERM) used in the treatment of estrogen-sensitive breast cancer. Tamoxifen itself only has weak anti-estrogen effects and must be converted into more active metabolites to have therapeutic activity. Metabolism takes place in the liver and is carried out primarily by cytochrome P450 enzymes. Tamoxifen is hydroxylated by CYP2D6 and demethylated by CYP3A4 and CYP3A5, producing the active metabolites 4-hydroxytamoxifen and endoxifen. These metabolites inhibit estrogen binding to estrogen receptors in breast cancer cells, which in turn inhibit tumour growth."
What is the definition of Erlotinib Action Pathway?,"Erlotinib is an anti-EGFR drug used in the treatment of some cancers. EGFR is linked multiple signalling pathways involved in tumour growth and angiogenesis such as the Ras/Raf pathway and the PI3K/Akt pathways. These pathways ultimately lead to the activation of transcription factors such as Jun, Fos, and Myc, as well as cyclin D1, which stimulates cell growth and mitosis. Uncontrolled cell growth and mitosis leads to cancer. Erlotinib acts as an anticancer drug by binding to the intracellular tyrosine kinase domain of the EGFR and blocking its activity. This in turn inhibits downstream signalling and prevents tumour growth."
What is the definition of Gefitinib Action Pathway?,"Gefitinib is an anti-EGFR drug used in the treatment of some cancers. EGFR is linked multiple signalling pathways involved in tumour growth and angiogenesis such as the Ras/Raf pathway and the PI3K/Akt pathways. These pathways ultimately lead to the activation of transcription factors such as Jun, Fos, and Myc, as well as cyclin D1, which stimulates cell growth and mitosis. Uncontrolled cell growth and mitosis leads to cancer. Gefitinib acts as an anticancer drug by binding to the intracellular tyrosine kinase domain of the EGFR and blocking its activity. This in turn inhibits downstream signalling and prevents tumour growth."
What is the definition of Cetuximab Action Pathway?,"Cetuximab is an anti-EGFR drug used in the treatment of some cancers. EGFR is linked multiple signalling pathways involved in tumour growth and angiogenesis such as the Ras/Raf pathway and the PI3K/Akt pathways. These pathways ultimately lead to the activation of transcription factors such as Jun, Fos, and Myc, as well as cyclin D1, which stimulates cell growth and mitosis. Uncontrolled cell growth and mitosis leads to cancer. Cetuximab acts as an anticancer drug by binding to the extracellular domain of the EGFR and preventing its activation by epidermal growth factor. This in turn inhibits downstream signalling and prevents tumour growth."
What is the definition of Panitumumab Action Pathway?,"Panitumumab is an anti-EGFR drug used in the treatment of some cancers. EGFR is linked multiple signalling pathways involved in tumour growth and angiogenesis such as the Ras/Raf pathway and the PI3K/Akt pathways. These pathways ultimately lead to the activation of transcription factors such as Jun, Fos, and Myc, as well as cyclin D1, which stimulates cell growth and mitosis. Uncontrolled cell growth and mitosis leads to cancer. Panitumumab acts as an anticancer drug by binding to the extracellular domain of the EGFR and preventing its activation by epidermal growth factor. This in turn inhibits downstream signalling and prevents tumour growth."
What is the definition of Trastuzumab Action Pathway?,"Trastuzumab is an anti-EGFR drug used in the treatment of HER2-positive breast cancer. EGFR is linked multiple signalling pathways involved in tumour growth and angiogenesis such as the Ras/Raf pathway and the PI3K/Akt pathways. These pathways ultimately lead to the activation of transcription factors such as Jun, Fos, and Myc, as well as cyclin D1, which stimulates cell growth and mitosis. Uncontrolled cell growth and mitosis leads to cancer. Trastuzumab acts as an anticancer drug by binding to the extracellular domain of the EGFR and preventing its activation by epidermal growth factor. This in turn inhibits downstream signalling and prevents tumour growth."
What is the definition of Capecitabine Action Pathway?,"Capecitabine is a fluoropyrimidine anticancer drug. After absorption, it is metabolized in the liver to the intermediate 5’-deoxy-5-fluorouridine, which is subsequently converted into 5-fluorouracil (5-FU) by intracellular thymidine phosphorylase. 5-FU exerts cytotoxic effects on the cell by direct incorporation into DNA and RNA as well as by inhibiting thymidylate synthase. Since thymidine phosphorylase is present at 3-10 fold higher concentration in cancer cells compared normal cells, capecitabine’s cytotoxic effect is selective for cancer cells. "
What is the definition of Fluorouracil Action Pathway?,"Fluorouracil (5-FU), sold under the brand name Adrucil among others, is a fluoropyrimidine anticancer drug. By injection into a vein, it is used to treat colon cancer, esophageal cancer, stomach cancer, pancreatic cancer, breast cancer, and cervical cancer. As a cream, it is used for actinic keratosis, basal cell carcinoma, and skin warts. Fluorouracil is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system (Wikipedia). Fluorouracil exerts cytotoxic effects on the cell by direct incorporation into DNA and RNA as well as by inhibiting thymidylate synthase."
What is the definition of Suprofen Action Pathway?,"Suprofen (also named Profenal and Maldocil) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to relieve pain (analgesic) and reduce fever (antipyretic). Suprofen is also a type of ophthalmic anti-inflammatory medicines which may be used to help prevent eye constrict for pupil during surgery. Suprofen can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Since prostaglandin is the messenger molecules in the process of inflammation; hence, inhibition of prostaglandin synthesis can reduce the pain and inflammation (e.g. in the eyes)."
What is the definition of Bromfenac Action Pathway?,"Bromfenac (also named Prolensa, Bromday or Xibrom) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to reduce ocular inflammation and pain after cataract surgery. Bromfenac is also a type of ophthalmic anti-inflammatory medicines. Bromfenac can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of bromfenac."
What is the definition of Indomethacin Action Pathway?,"Indomethacin (also named Amuno or Indocid) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat prostaglandin G/H synthase related fever, swelling, pain and inflammation.  Indomethacin can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis is caused by presence of indomethacin."
What is the definition of Mefenamic Acid Action Pathway?,"Mefenamic acid (also named Ponstel) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to relieve pain (analgesic) and reduce fever (antipyretic). Mefenamic acid can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Since prostaglandin is the messenger molecules in the process of inflammation; hence, inhibition of prostaglandin synthesis can reduce the pain, fever and inflammation."
What is the definition of Oxaprozin Action Pathway?,"Oxaprozin (also named Daypro, Dayrun) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to relieve pain (analgesic) and reduce fever (antipyretic). Oxaprozin is also a type of ophthalmic anti-inflammatory medicines which may be used to help prevent eye constrict for pupil during surgery. Oxaprozin can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Since prostaglandin is the messenger molecules in the process of inflammation; hence, inhibition of prostaglandin synthesis can reduce the pain and inflammation. "
What is the definition of Nabumetone Action Pathway?,"Nabumetone (also named Relafen and Relifex) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to relieve pain (analgesic) and reduce fever (antipyretic). Nabumetone can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Since prostaglandin is the messenger molecules in the process of inflammation; hence, inhibition of prostaglandin synthesis can reduce the pain, fever and inflammation."
What is the definition of Naproxen Action Pathway?,"Naproxen (also named Aleve and Naprosyn) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to relieve pain (analgesic) and reduce fever (antipyretic). Naproxen is also a type of ophthalmic anti-inflammatory medicines. Naproxen can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Since prostaglandin is the messenger molecules in the process of inflammation; hence, inhibition of prostaglandin synthesis can reduce the pain and inflammation. "
What is the definition of Diflunisal Action Pathway?,"Diflunisal (also known as Dolobid) is a prostaglandin G/H synthase inhibitor that can inhibit prostaglandin G/H synthase 1 and 2 which prevent the production of prostaglandin. Therefore, diflunisal can be used for treating prostaglandin-associated pain, fever, swelling, platelet aggregation and inflammation. Diflunisal can also inhibit the relocation of leukocytes to inflammation site and also the production of the aggregating agent of platelets: thromboxane A2."
What is the definition of Azathioprine Action Pathway?,"Azathioprine is a purine antimetabolite prodrug that exerts cytotoxic effects via three mechanisms: via incorporation of thiodeoxyguanosine triphosphate into DNA and thioguanosine triphosphate into RNA, inhibition of de novo synthesis of purine nucleotides, and inhibition of Ras-related C3 botulinum toxin substrate 1, which induces apoptosis of activated T cells. Azathioprine is first converted _in vivo_ to mercaptopurine in the liver. Mercaptopurine then travels through the bloodstream and is transported into cells via nucleoside transporters.  Mercaptopurine is converted to thioguanosince diphosphate through a series of metabolic reactions that produces the metabolic intermediates, thioinosine 5’-monophosphate, thioxanthine monophosphate, and thioguanosine monophosphate. Thioguanosine diphosphate is then converted via a thiodeoxyguanosine diphosphate intermediate to thiodeoxyguanosine triphosphate, which is incorporated into DNA. Thioguanosine diphosphate is also converted to thioguanosine triphosphate which is incorporated into RNA. The thioguanosine triphosphate metabolite also inhibits Ras-related C3 botulinum toxin substrate 1, a plasma membrane-associated small GTPase that regulates cellular processes, inducing apoptosis in activated T cells. Finally, de novo synthesis of purine nucleotides is inhibited by the methyl-thioinosine 5’-monophosphate metabolite, which inhibits amidophosphoribosyl-transferase, the enzyme that catalyzes one of the first steps in this pathway."
What is the definition of Mercaptopurine Action Pathway?,"Mercaptopurine is a purine antimetabolite prodrug that exerts cytotoxic effects via three mechanisms: via incorporation of thiodeoxyguanosine triphosphate into DNA and thioguanosine triphosphate into RNA, inhibition of de novo synthesis of purine nucleotides, and inhibition of Ras-related C3 botulinum toxin substrate 1, which induces apoptosis of activated T cells. Mercaptopurine travels through the bloodstream and is transported into cells via nucleoside transporters.  Mercaptopurine is then converted to thioguanosince diphosphate through a series of metabolic reactions that produces the metabolic intermediates, thioinosine 5’-monophosphate, thioxanthine monophosphate, and thioguanosine monophosphate. Thioguanosine diphosphate is then converted via a thiodeoxyguanosine diphosphate intermediate to thiodeoxyguanosine triphosphate, which is incorporated into DNA. Thioguanosine diphosphate is also converted to thioguanosine triphosphate which is incorporated into RNA. The thioguanosine triphosphate metabolite also inhibits Ras-related C3 botulinum toxin substrate 1, a plasma membrane-associated small GTPase that regulates cellular processes, inducing apoptosis in activated T cells. Finally, de novo synthesis of purine nucleotides is inhibited by the methyl-thioinosine 5’-monophosphate metabolite, which inhibits amidophosphoribosyl-transferase, the enzyme that catalyzes one of the first steps in this pathway."
What is the definition of Methotrexate Action Pathway?,"Methotrexate is an antifolate antimetabolite used in the treatment of rheumatoid arthritis and cancer. Methotrexate is taken up into the cell by human reduced folate carriers (SLC19A1).  In the cytoplasm, methotrexate is polyglutamated by folylpolyglutamate synthase, which enhances its retention inside the cell. Both methotrexate and methotrexate-polyglutamate inhibit dihydrofolate reductase, an enzyme that catalyzes the conversion of dihydrofolate into tetrahydrofolate, which is the active form of folic acid. Tetrahydrofolate is involved in many single-carbon transfer reactions, including the synthesis of DNA and RNA nucleotides. Inhibition of dihydrofolate reductase causes depletion of intracellular tetrahydrofolate, which has a cytotoxic effect, especially on rapidly dividing cells. Methotrexate-polyglutamate further inhibits de novo purine synthesis and thymidylate synthase, which contribute to methotrexate’s cytotoxic effects."
What is the definition of Lovastatin Action Pathway?,"Lovastatin (also known as Mevacor or Mevinolin) is a statin drug (hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors) that can be used for lowering cholesterol, treating hypercholesterolemia and preventing myocardial infarction and stroke. Lovastatin is produced by fermentation of Aspergillus terreus. HMG-CoA catalyzes the conversion of HMG-CoA to mevalonic acid, the rate-limiting step of cholesterol biosynthesis. Lovastatin, like simvastin, is a prodrug. These prodrugs are converted to their active form by in vivo hydrolysis of the lactone ring. The hydrolyzed lactone ring resembles the tetrahedral reaction intermediate produced by HMG-CoA reductase and the bicyclic portions of these compounds bind to the coenzyme A site of the enzyme. The active drug concentrates in the liver during first-pass circulation. Cholesterol biosynthesis accounts for approximately 80% of cholesterol in the body; thus, inhibiting this process can significantly lower cholesterol levels."
What is the definition of Zoledronate Action Pathway?,"Zoledronate (also named zoledronic acid, Zometa or Reclast) is a type of medication that used to treat numbers of bone diseases because of its affinity for hydroxyapatite. Zoledronate targets farnesyl pyrophosphate (FPP) synthase by inhibiting the function of this enzyme in the mevalonate pathway, which prevent the biosynthesis of Geranyl-PP and farnesyl pyrophosphate. Geranyl-PP and farnesyl pyrophosphate are important for geranylgeranylation and farnesylation of GTPase signalling proteins. Lack of Geranyl-PP and farnesyl pyrophosphate will result in decreased rate of bond resorption and turnover as well as block the osteoclast activity, which lead to an increasing mass gain in bone (i.e. net gain in bone mass). "
What is the definition of Cerivastatin Action Pathway?,"Cerivastatin inhibits cholesterol synthesis via the mevalonate pathway by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. HMG-CoA reductase is the enzyme responsible for the conversion of HMG-CoA to mevalonic acid, the rate-limiting step of cholesterol synthesis by this pathway. Cerivastatin bears a chemical resemblance to the reduced HMG-CoA reaction intermediate that is formed during catalysis. Cerivastatin, like fluvastatin, atorvastatin and rosuvastatin, is one of the synthetically derived statins. Cholesterol biosynthesis accounts for approximately 80% of cholesterol in the body; thus, inhibiting this process can significantly lower cholesterol levels. "
What is the definition of Risedronate Action Pathway?,"Risedronate (also named Actonel, Atelvia or Benet.) is a type of medication that used to treat numbers of bone diseases because of its affinity for hydroxyapatite. Risedronate targets farnesyl pyrophosphate (FPP) synthase by inhibiting the function of this enzyme in the mevalonate pathway, which prevent the biosynthesis of Geranyl-PP and farnesyl pyrophosphate. Geranyl-PP and farnesyl pyrophosphate are important for geranylgeranylation and farnesylation of GTPase signalling proteins. Lack of Geranyl-PP and farnesyl pyrophosphate will result in decreased rate of bond resorption and turnover as well as block the osteoclast activity, which lead to an increasing mass gain in bone (i.e. net gain in bone mass). "
What is the definition of Pamidronate Action Pathway?,"Ibandronate (also named ibandronate sodium) is a type of medication that used to treat numbers of bone diseases because of its affinity for hydroxyapatite. Ibandronate targets farnesyl pyrophosphate (FPP) synthase by inhibiting the function of this enzyme in the mevalonate pathway, which prevent the biosynthesis of Geranyl-PP and farnesyl pyrophosphate. Geranyl-PP and farnesyl pyrophosphate are important for geranylgeranylation and farnesylation of GTPase signalling proteins. Lack of Geranyl-PP and farnesyl pyrophosphate will result in decreased rate of bond resorption and turnover as well as block the osteoclast activity, which lead to an increasing mass gain in bone (i.e. net gain in bone mass). "
What is the definition of Fluvastatin Action Pathway?,"Fluvastatin inhibits cholesterol synthesis via the mevalonate pathway by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. HMG-CoA reductase is the enzyme responsible for the conversion of HMG-CoA to mevalonic acid, the rate-limiting step of cholesterol synthesis by this pathway. Fluvastatin bears a chemical resemblance to the reduced HMG-CoA reaction intermediate that is formed during catalysis. Fluvastatin was the first synthetically-prepared HMG-CoA reductase inhibitor. Although similar to lovastatin, simvastatin, and pravastatin, it has a shorter half-life, no active metabolites, extensive protein binding, and minimal CSF penetration. Cholesterol biosynthesis accounts for approximately 80% of cholesterol in the body; thus, inhibiting this process can significantly lower cholesterol levels. "
What is the definition of Atorvastatin Action Pathway?,"Atorvastatin inhibits cholesterol synthesis via the mevalonate pathway by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase. HMG-CoA reductase is the enzyme responsible for the conversion of HMG-CoA to mevalonic acid, the rate-limiting step of cholesterol synthesis by this pathway. Atorvastatin bears a chemical resemblance to the reduced HMG-CoA reaction intermediate that is formed during catalysis. Structure-activity relationship studies have demonstrated that atorvastatin binds to HMG-CoA reductase at the same site as the reduced intermediate and are held in place by similar chemical interactions. Cholesterol biosynthesis accounts for approximately 80% of cholesterol in the body; thus, inhibiting this process can significantly lower cholesterol levels. Atorvastatin has a unique structure, long half-life, and hepatic selectivity, explaining its greater LDL-lowering potency compared to other HMG-CoA reductase inhibitors."
What is the definition of Meloxicam Action Pathway?,"Meloxicam is a non-steroidal anti-inflammatory drug (NSAID) with antipyretic and analgesic properties. Most NSAIDs, such as ibuprofen and naproxen, are non-selective prostaglandin G/H synthase (a.k.a. cyclooxygenase or COX) inhibitors that act on both prostaglandin G/H synthase 1 and 2 (COX-1 and -2). COX catalyzes the conversion of arachidonic acid to prostaglandin G2 (PGG2) and PGG2 to prostaglandin H2 (PGH2). PGH2 is the precursor to a number of prostaglandins (e.g. PGE2) involved in fever, pain, swelling and inflammation. Meloxicam antagonizes COX by binding to the upper portion of the active site, preventing its substrate, arachidonic acid, from entering the active site. Although it was previously thought that meloxicam is a non-selective COX inhibitor, it is now known that it has higher selectivity for COX-2. Selective COX-2 inhibitors are thought to have more potent anti-inflammatory and analgesic properties with decreased adverse gastric effects. The analgesic, antipyretic and anti-inflammatory effects of meloxicam occur as a result of decreased prostaglandin synthesis.  The first part of this figure depicts the anti-inflammatory, analgesic and antipyretic pathway of meloxicam. The latter portion of this figure depicts meloxicam’s potential involvement in platelet aggregation. Prostaglandin synthesis varies across different tissue types. Platelets, anuclear cells derived from fragmentation from megakaryocytes, contain COX-1, but not COX-2. COX-1 activity in platelets is required for thromboxane A2 (TxA2)-mediated platelet aggregation. Platelet activation and coagulation do not normally occur in intact blood vessels. After blood vessel injury, platelets adhere to the subendothelial collagen at the site of injury. Activation of collagen receptors initiates phospholipase C (PLC)-mediated signaling cascades resulting in the release of intracellular calcium from the dense tubula system. The increase in intracellular calcium activates kinases required for morphological change, transition to procoagulant surface, secretion of granular contents, activation of glycoproteins, and the activation of phospholipase A2 (PLA2). Activation of PLA2 results in the liberation of arachidonic acid, a precursor to prostaglandin synthesis, from membrane phospholipids. The accumulation of TxA2, ADP and thrombin mediates further platelet recruitment and signal amplification. TxA2 and ADP stimulate their respective G-protein coupled receptors, thomboxane A2 receptor and P2Y purinoreceptor 12, and inhibit the production of cAMP via adenylate cyclase inhibition. This counteracts the adenylate cyclase stimulatory effects of the platelet aggregation inhibitor, PGI2, produced by neighbouring endothelial cells. Platelet adhesion, cytoskeletal remodeling, granular secretion and signal amplification are independent processes that lead to the activation of the fibrinogen receptor. Fibrinogen receptor activation exposes fibrinogen binding sites and allows platelet cross-linking and aggregation to occur. Neighbouring endothelial cells found in blood vessels express both COX-1 and COX-2. COX-2 in endothelial cells mediates the synthesis of PGI2, an effective platelet aggregation inhibitor and vasodilator, while COX-1 mediates vasoconstriction and stimulates platelet aggregation. PGI2 produced by endothelial cells encounters platelets in the blood stream and binds to the G-protein coupled prostacyclin receptor. This causes G-protein mediated activation of adenylate cyclase, which catalyzes the conversion of adenosine triphosphate (ATP) to cyclic AMP (cAMP). Four cAMP molecules then bind to the regulatory subunits of the inactive cAMP-dependent protein kinase holoenzyme causing dissociation of the regulatory subunits and leaving two active catalytic subunit monomers. The active subunits of cAMP-dependent protein kinase catalyze the phosphorylation of a number of proteins. Phosphorylation of inositol 1,4,5-trisphosphate receptor type 1 on the endoplasmic reticulum (ER) inhibits the release of calcium from the ER. This in turn inhibits the calcium-dependent events, including PLA2 activation, involved in platelet activation and aggregation. Inhibition of PLA2 decreases intracellular TxA2 and inhibits the platelet aggregation pathway. cAMP-dependent kinase also phosphorylates the actin-associated protein, vasodilator-stimulated phosphoprotein. Phosphorylation inhibits protein activity, which includes cytoskeleton reorganization and platelet activation. Meloxicam preferentially inhibits COX-2 with little activity against COX-1. COX-2 inhibition in endothelial cells decreases the production of PGI2 and the ability of these cells to inhibit platelet aggregation and stimulate vasodilation. These effects are thought to be responsible for the adverse cardiovascular effects observed with other selective COX-2 inhibitors, such as rofecoxib, which has since been withdrawn from the market. "
What is the definition of Valdecoxib Action Pathway?,"Valdecoxib, a selective prostaglandin G/H synthase 2 (better known as cyclooxygenase-2 or COX-2) inhibitor, is classified as a nonsteroidal anti-inflammatory drug (NSAID). Valdecoxib was used for its anti-inflammatory, analgesic, and antipyretic effects in the management of osteoarthritis and for the treatment of dysmenorrhea or acute pain. Unlike celecoxib, valdecoxib lacks a sulfonamide chain and does not require CYP450 enzymes for metabolism. Both COX-1 and COX-2 catalyze the conversion of arachidonic acid to prostaglandin G2 (PGG2) and PGG2 to prostaglandin H2 (PGH2). PGH2 is the precursor of a number of prostaglandins, including prostaglandin E2 (PGE2), prostaglandin I2 (PGI2) and thomboxane A2 (TxA2). Valdecoxib selectively inhibits the cyclooxygenase-2 (COX-2) enzyme, a key enzyme in the production of PGE2. PGE2 is a potent mediator of pain, inflammation and fever. The first part of this figure depicts the anti-inflammatory, analgesic and antipyretic pathway of valdecoxib. The latter portion of this figure depicts valdecoxib’s potential involvement in platelet aggregation. Prostaglandin synthesis varies across different tissue types. Platelets, anuclear cells derived from fragmentation from megakaryocytes, contain COX-1, but not COX-2. COX-1 activity in platelets is required for thromboxane A2 (TxA2)-mediated platelet aggregation. Platelet activation and coagulation do not normally occur in intact blood vessels. After blood vessel injury, platelets adhere to the subendothelial collagen at the site of injury. Activation of collagen receptors initiates phospholipase C (PLC)-mediated signaling cascades resulting in the release of intracellular calcium from the dense tubula system. The increase in intracellular calcium activates kinases required for morphological change, transition to procoagulant surface, secretion of granular contents, activation of glycoproteins, and the activation of phospholipase A2 (PLA2). Activation of PLA2 results in the liberation of arachidonic acid, a precursor to prostaglandin synthesis, from membrane phospholipids. The accumulation of TxA2, ADP and thrombin mediates further platelet recruitment and signal amplification. TxA2 and ADP stimulate their respective G-protein coupled receptors, thomboxane A2 receptor and P2Y purinoreceptor 12, and inhibit the production of cAMP via adenylate cyclase inhibition. This counteracts the adenylate cyclase stimulatory effects of the platelet aggregation inhibitor, PGI2, produced by neighbouring endothelial cells. Platelet adhesion, cytoskeletal remodeling, granular secretion and signal amplification are independent processes that lead to the activation of the fibrinogen receptor. Fibrinogen receptor activation exposes fibrinogen binding sites and allows platelet cross-linking and aggregation to occur. Neighbouring endothelial cells found in blood vessels express both COX-1 and COX-2. COX-2 in endothelial cells mediates the synthesis of PGI2, an effective platelet aggregation inhibitor and vasodilator, while COX-1 mediates vasoconstriction and stimulates platelet aggregation. PGI2 produced by endothelial cells encounters platelets in the blood stream and binds to the G-protein coupled prostacyclin receptor. This causes G-protein mediated activation of adenylate cyclase, which catalyzes the conversion of adenosine triphosphate (ATP) to cyclic AMP (cAMP). Four cAMP molecules then bind to the regulatory subunits of the inactive cAMP-dependent protein kinase holoenzyme causing dissociation of the regulatory subunits and leaving two active catalytic subunit monomers. The active subunits of cAMP-dependent protein kinase catalyze the phosphorylation of a number of proteins. Phosphorylation of inositol 1,4,5-trisphosphate receptor type 1 on the endoplasmic reticulum (ER) inhibits the release of calcium from the ER. This in turn inhibits the calcium-dependent events, including PLA2 activation, involved in platelet activation and aggregation. Inhibition of PLA2 decreases intracellular TxA2 and inhibits the platelet aggregation pathway. cAMP-dependent kinase also phosphorylates the actin-associated protein, vasodilator-stimulated phosphoprotein. Phosphorylation inhibits protein activity, which includes cytoskeleton reorganization and platelet activation. Valdexocib preferentially inhibits COX-2 with little activity against COX-1. COX-2 inhibition in endothelial cells decreases the production of PGI2 and the ability of these cells to inhibit platelet aggregation and stimulate vasodilation. These effects are thought to be responsible for the rare, but severe, adverse cardiovascular effects observed with rofecoxib, a COX-2 inhibitor which was subsequently been withdrawn from the market. Valdexocib was withdrawn from the Canadian, U.S. and E.U. markets in 2005 due to concerns of possible increased risk of heart attack and stroke. "
What is the definition of Candesartan Action Pathway?,"Candesartan (also named Blopress or Atacand) is an active metabolite of angiotensin II receptor blockers (ARBs) pro drug, candesartan cilexetil. Candesartan cilexetil converts to candesartan rapidly in gastrointestinal tract during absorption. Candesartan competes with angiotensin II to bind type-1 angiotensin II receptor (AT1) in many tissues (e.g. vascular smooth muscle, the adrenal glands, etc.) to prevent increasing sodium, water reabsorption and peripheral resistance (that will lead to increasing blood pressure) via aldosterone secretion that is caused by angiotensin II. Therefore, action of candesartan binding to AT1 will result in decreasing blood pressure. For more information on the effects of aldosterone on electrolyte and water excretion, refer to the description of the \spironolactone\:http://pathman.smpdb.ca/pathways/SMP00134/pathway or \triamterene\:http://pathman.smpdb.ca/pathways/SMP00132/pathway pathway, which describes the mechanism of direct aldosterone antagonists. Candesartan is an effective agent for reducing blood pressure and may be used to treat essential hypertension and heart failure."
What is the definition of Eprosartan Action Pathway?,"Eprosartan (also named Teveten) is an antagonist of angiotensin II receptor blockers (ARBs). Eprosartan competes with angiotensin II to bind type-1 angiotensin II receptor (AT1) in many tissues (e.g. vascular smooth muscle, the adrenal glands, etc.) to prevent increasing sodium, water reabsorption and peripheral resistance (that will lead to increasing blood pressure) via aldosterone secretion that is caused by angiotensin II. Therefore, action of eprosartan binding to AT1 will result in decreasing blood pressure. For more information on the effects of aldosterone on electrolyte and water excretion, refer to the description of the \spironolactone\:http://pathman.smpdb.ca/pathways/SMP00134/pathway or \triamterene\:http://pathman.smpdb.ca/pathways/SMP00132/pathway pathway, which describes the mechanism of direct aldosterone antagonists. Eprosartan is an effective agent for reducing blood pressure and may be used to treat essential hypertension and heart failure."
What is the definition of Irbesartan Action Pathway?,"Irbesartan (also named Avapro) is an antagonist of angiotensin II receptor blockers (ARBs). Irbesartan competes with angiotensin II to bind type-1 angiotensin II receptor (AT1) in many tissues (e.g. vascular smooth muscle, the adrenal glands, etc.) to prevent increasing sodium, water reabsorption and peripheral resistance (that will lead to increasing blood pressure) via aldosterone secretion that is caused by angiotensin II. Therefore, action of irbesartan binding to AT1 will result in decreasing blood pressure. For more information on the effects of aldosterone on electrolyte and water excretion, refer to the description of the \spironolactone\:http://pathman.smpdb.ca/pathways/SMP00134/pathway or \triamterene\:http://pathman.smpdb.ca/pathways/SMP00132/pathway pathway, which describes the mechanism of direct aldosterone antagonists. Irbesartan is an effective agent for reducing blood pressure and may be used to treat essential hypertension and heart failure."
What is the definition of Losartan Action Pathway?,"Losartan (also named Cozaar) is an active metabolite of angiotensin II receptor blockers (ARBs). Losartan competes with angiotensin II to bind type-1 angiotensin II receptor (AT1) in many tissues (e.g. vascular smooth muscle, the adrenal glands, etc.) to prevent increasing sodium, water reabsorption and peripheral resistance (that will lead to increasing blood pressure) via aldosterone secretion that is caused by angiotensin II. Therefore, action of losartan binding to AT1 will result in decreasing blood pressure. For more information on the effects of aldosterone on electrolyte and water excretion, refer to the description of the \spironolactone\:http://pathman.smpdb.ca/pathways/SMP00134/pathway or \triamterene\:http://pathman.smpdb.ca/pathways/SMP00132/pathway pathway, which describes the mechanism of direct aldosterone antagonists. Losartan is an effective agent for reducing blood pressure and may be used to treat essential hypertension and heart failure."
What is the definition of Olmesartan Action Pathway?,"Olmesartan (also named Benicar or Olmetec) is an active metabolite of angiotensin II receptor blockers (ARBs) pro drug, olmesartan medoxomil. Olmesartan medoxomi converts to olmesartan rapidly in gastrointestinal tract during absorption. Olmesartan competes with angiotensin II to bind type-1 angiotensin II receptor (AT1) in many tissues (e.g. vascular smooth muscle, the adrenal glands, etc.) to prevent increasing sodium, water reabsorption and peripheral resistance (that will lead to increasing blood pressure) via aldosterone secretion that is caused by angiotensin II. Therefore, action of olmesartan binding to AT1 will result in decreasing blood pressure. For more information on the effects of aldosterone on electrolyte and water excretion, refer to the description of the \spironolactone\:http://pathman.smpdb.ca/pathways/SMP00134/pathway or \triamterene\:http://pathman.smpdb.ca/pathways/SMP00132/pathway pathway, which describes the mechanism of direct aldosterone antagonists. Olmesartan is an effective agent for reducing blood pressure and may be used to treat essential hypertension and heart failure."
What is the definition of Telmisartan Action Pathway?,"Telmisartan (also named Micardis) is an antagonist of angiotensin II receptor blockers (ARBs). Telmisartan competes with angiotensin II to bind type-1 angiotensin II receptor (AT1) in many tissues (e.g. vascular smooth muscle, the adrenal glands, etc.) to prevent increasing sodium, water reabsorption and peripheral resistance (that will lead to increasing blood pressure) via aldosterone secretion that is caused by angiotensin II. Therefore, action of telmisartan binding to AT1 will result in decreasing blood pressure. For more information on the effects of aldosterone on electrolyte and water excretion, refer to the description of the \spironolactone\:http://pathman.smpdb.ca/pathways/SMP00134/pathway or \triamterene\:http://pathman.smpdb.ca/pathways/SMP00132/pathway pathway, which describes the mechanism of direct aldosterone antagonists. Telmisartan is an effective agent for reducing blood pressure and may be used to treat essential hypertension and heart failure."
What is the definition of Valsartan Action Pathway?,"Valsartan (also named Diovan) is an antagonist of angiotensin II receptor blockers (ARBs). Valsartan competes with angiotensin II to bind type-1 angiotensin II receptor (AT1) in many tissues (e.g. vascular smooth muscle, the adrenal glands, etc.) to prevent increasing sodium, water reabsorption and peripheral resistance (that will lead to increasing blood pressure) via aldosterone secretion that is caused by angiotensin II. Therefore, action of valsartan binding to AT1 will result in decreasing blood pressure. For more information on the effects of aldosterone on electrolyte and water excretion, refer to the description of the \spironolactone\:http://pathman.smpdb.ca/pathways/SMP00134/pathway or \triamterene\:http://pathman.smpdb.ca/pathways/SMP00132/pathway pathway, which describes the mechanism of direct aldosterone antagonists. Valsartan is an effective agent for reducing blood pressure and may be used to treat essential hypertension and heart failure."
What is the definition of Clopidogrel Action Pathway?,"Clopidogrel, an antiplatelet agent structurally and pharmacologically similar to ticlopidine, is used to reduce atherosclerotic events such as myocardial infarction, stroke, and vascular death in patients who have had a recent stroke, recent MI, or have established peripheral vascular disease. The active metabolite of clopidogrel prevents binding of adenosine diphosphate (ADP) to its platelet receptor, impairing the ADP-mediated activation of the glycoprotein GPIIb/IIIa complex. It is proposed that the inhibition involves a defect in the mobilization from the storage sites of the platelet granules to the outer membrane. No direct interference occurs with the GPIIb/IIIa receptor. As the glycoprotein GPIIb/IIIa complex is the major receptor for fibrinogen, its impaired activation prevents fibrinogen binding to platelets and inhibits platelet aggregation. By blocking the amplification of platelet activation by released ADP, platelet aggregation induced by agonists other than ADP is also inhibited by the active metabolite of clopidogrel. "
What is the definition of Ticlopidine Action Pathway?,"Ticlopidine, marketed as Ticlid, is an antiplatelet drug that targets the P2Y12 receptor of platelets. Ticlopidine is taken orally and is a prodrug that must be metabolically activated before it can be effective. It first enters the liver and enters the endoplasmic reticulum where it is metabolized to form the active metabolite. First, it is catalyzed by cytochromes P450 2C19, 2B6 and 1A2 into 2-oxoclopidogrel. Secondly, it is processed by cytochromes P450 2B6, 2C9, 2C19, 3A4, 3A5, and serum paraoxonase/arylesterase 1 into the active metabolite of clopidogrel. The active metabolite of clopidogrel then enters the blood stream, where it binds irreversibly to the P2Y purinoreceptor 12 on the surface of platelet cells, preventing ADP from binding to and activating it. Clopidogrel prevents the activation of the Gi protein associated with the P2Y12 receptor from inactivating adenylate cyclase in the platelet, leading to a buildup of cAMP. This cAMP then activates calcium efflux pumps, preventing calcium buildup in the platelet, which would cause activation, and later, aggregation."
What is the definition of Clomocycline Action Pathway?,"Clomocycline is a tetracycline antibiotic that inhibits bacterial cell growth by inhibiting translation. Clomocycline is lipophilic and easily diffuses across cell membranes or enters cells via porin channels in the bacterial membrane. It binds to the 30S ribosomal subunit and prevents the aminoacyl tRNA from binding to the A site of the ribosome-RNA complex. Clomocycline binding is reversible in nature. Clomocycline may be used to treat acne, gum disease, and other bacterial infections such as chalmydia, brucellosis, bartonellosis and cholera. Clomocycline is also effective against certain strains of malaria and may also be prescribed for the treatment of Lyme disease. "
What is the definition of Cilostazol Action Pathway?,"Cilostazol, also sold as Pletal, is a drug used to prevent platelet aggregation, specifically treating symptoms of intermittent claudication caused by peripheral artery disease as well as preventing strokes.Cilostazol is ingested orally, and it enters the liver, where it is metabolized in the endoplasmic reticulum by cytochrome P450 3A4 into 4-hydroxycilostazol, and by cytochrome P450 2C19 and 3A5 into 4-cis-hydroxycilostazol. Each of these metabolites is further metabolized, 4-hydroxycilostazol into 3,4-dehydrocilostazol and 4-cis-hydroxycilostazol into 4'-trans-hydroxycilostazol respectively. These two metabolites are the active metabolites, and they both act to inhibit the action of cAMP-specific 3',5'-cyclic phosphodiesterase 4D in platelets. With this enzyme inhibited, it is unable to metabolize cAMP into AMP, which leads to a buildup of cAMP in the blood. cAMP in turn is known to prevent aggregation of platelets, by inhibiting their adhesion to collagen, as well as decreasing the amount of calcium within the cytosol, preventing granule release, which then prevents activation of other platelets."
What is the definition of Dipyridamole (Antiplatelet) Action Pathway?,"Dipyridamole (also known as Persantine) can bind and inhibit cAMP-specific 3',5'-cyclic phosphodiesterase 4D at platelet cell, which prevent the release of arachidonic acid form membrane phospholipids that eventually decreasing thromboxane A2 activity. Dipyridamole can also induce adenylate cyclase activity by releasing prostacyclin, which lead to inhibition of platelet aggregation and increased intraplatelet concentration of cAMP."
What is the definition of Abciximab Action Pathway?,"Abciximab (also known as c7E3 Fab) is integrin (integrin alpha-IIb and integrin beta-3) receptor antagonist. Binding of abciximab to integrin receptor will block any large molecule to attach on the receptor, which will lead to block any associated signal transduction pathways."
What is the definition of Eptifibatide Action Pathway?,"Eptifibatide (also named Integrilin) is an anti-coagulant drug that is produced from Sistrurus miliarus barbouri, which can block platelet glycoprotein IIb/IIIa receptor to prevent platelet aggregation. Although, inhibition of platelet aggregation occurs in a dose- and concentration-dependent manner. "
What is the definition of Tirofiban Action Pathway?,"Tirofiban is a reversible antagonist of fibrinogen binding to the GP IIb/IIIa receptor, the major platelet surface receptor involved in platelet aggregation. Platelet aggregation inhibition is reversible following cessation of the infusion of tirofiban."
What is the definition of Enoxaparin Action Pathway?,"Enoxaparin is a low molecular weight heparin used to reduce cardiovascular events. Enoxaparin's action is antithrombin-dependent. The drug binds to antithrombin III to reduce thrombin inhibition in the plasma. The drug increases the inactivation of coagulation factors IXa, Xa and XIIa. This increases the antithrombin effects. Compared to unfractionated heparin, low molecular weight heparins have lower affinity for plasma proteins and therefore only few are protein bound. They also are not inactivated by platelet factor 4 and does not bind endothelial cells or macrophages thus are not degraded as fast. Therefore, low molecular weight heparins like Enoxaparin are more stable and predictable heparins. "
What is the definition of Fondaparinux Action Pathway?,"Fondaparinux, also known as Arixtra, is an anticoagulant medication. It is part of a class of antithrombotic drugs, the first of this new class. In the blood capillary bed, Fondaparinux sodium activates antithrombin III. Then zooming in even further to the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide uses vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase. This enzyme also catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V and prothrombin. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced, which then uses fibrinogen alphabet, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator through plasminogen and creates fibrin degradation products. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa. From there, this protein complex is catalyzed into prothrombinase complex, the group of proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Heparin Action Pathway?,"Heparin (also named unfractionated heparin or Clexane) is an anticoagulant medication. The main mechanism of heparin is acting on increasing the rate of antithrombin-related neutralization of coagulation factors for certain activated type. More specifically, heparin will bind to the antithrombin III (AT) that make antithrombin III changing to its activated form. Activated antithrombin III will inactive prothrombin and factor Xa (also other proteases). "
What is the definition of Ardeparin Action Pathway?,"Ardeparin, trade name Normiflo, is low molecular weight heparin with anticoagulant effects used to prevent thrombosis. Ardeparin binds and increases antithrombin III activity and inactivates thrombin, factor Xa and coagulation factors XIIa, XIa, plasmin and kallikrein to prevent clot formation. In addition, heparin cofactor II is bound by ardeparin to inhibit thrombin. Plasma proteins have a smaller affinity for low molecular weight heparins than unfractionated heparin. Low molecular weight heparins also don't undergo the rapid degradation of unfractionated heparins. These properties increase ardeparin's bioavailability and give a more predictable anticoagulant activity."
What is the definition of Argatroban Action Pathway?,"Argatroban is a synthetic derivate of L-arginine and a direct thrombin inhibitor anticoagulant prescribed to patients with heparin-induced thrombocytopenia. Direct thrombin inhibitors bind plasma and fibrin bound thrombin independently of co-factor antithrombin.The inhibition of thrombin reduces the stability of the clot and promotes clot break down. Argatroban does not effect serine proteases like, trypsin, factor Xa, plasmin, and kallikrein.  Argatroban is advantageous, particularly for renal failure patients, due to its short-half life and hepatic clearance. "
What is the definition of Bivalirudin Action Pathway?,"Bivalirudin, trade name angiomax, is a direct thrombin inhibitor. It is often prescribed to patients who cannot take unfractionated or low molecular weight heparin. Bivalirudin does not need cofactor antithrobin to act. It binds circulating and clot-bound thrombin at the catalytic site and the anion binding exosite. The inhibition of fibrin prevents the cleavage of fibrinogen into fibrin which activates Factor XIII and Factor XIIIa. This destabilizes the thrombus and inhibits the promotion of thrombin production and platelet activation. As a result, bivalirudin prevents or reduces clot formation. "
What is the definition of Lepirudin Action Pathway?,Lepirudin (also known as Refludan) is an anticoagulant that can be used for inhibiting thrombin (prothrombin) irreversibly. Binding of thrombin can prevent formation of clot as well as thrombus.  Lepirudin can also reduce thrombocytopenia and break up clot.
What is the definition of Ximelagatran Action Pathway?,"Ximelagatran is an anticoagulant drug used to prevent and treat blood clots, and was the first drug in the anticoagulant drug class to be able to be ingested orally. It was discontinued from distribution by its parent company AstraZeneca in 2006 as it was found to raise liver enzyme levels in patients and cause liver damage as a result. Ximelagatran inhibits prothrombin. Then zooming in even further to the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide uses vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase. This enzyme also catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin, and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is inhibited by ximelagatran, and is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V and ximelagatran inhibits prothrombin. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced and inhibited by ximelagatran, which then uses fibrinogen alphabet, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator through plasminogen and creates fibrin degradation products. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa. Prothrombin is inhibited by ximelagatran here as well. From there, this protein complex is catalyzed into prothrombinase complex, the group of                                                                                                   proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Alteplase Action Pathway?,"Alteplase is the generic version of the drugs Activase and Actilyse. It is a thrombolytic drug prescribed to treat acute myocardial infarctions and other blood clotting conditions. Alteplase if often used to treat ischaemic stroke within hours of onset. The drug acts by breaking up blood clots. Alteplase binds fibrin in the blood clot to converts plasminogen to plasmin. Plasmin is a proteolytic enzyme that causing the degradation of fibrin. A side effect of the drug is bleeding, angioedema, allergic reactions and fever. "
What is the definition of Anistreplase Action Pathway?,"Anistreplase, trade name Eminase, is a thrombolytic drug prescribed to treat acute myocardial infarction. The drug is an acylated streptokinase-plasminogen complex. The acylation of the drug renders it temporarily inactive, protecting it from plasmin inhibitors. Anistreplase is deacylated following injection, activating the drug to increase thrombolysis by increasing plasminogen's conversion to plasmin. Plasmin breaks down the fibrin of the thrombus to break up the clot and release arterial blockages. Anistreplase has been shown to be very effective when administered shortly after onset of chest pain. Compared to other thrombolytic drugs, Anistreplase has a longer plasma half-life. It also advantageous as it can be given as a single bolus intravenous injection. "
What is the definition of Streptokinase Action Pathway?,"Streptokinase, or SK, is an enzyme and also a thrombolytic medication. We are focusing on the medication in this pathway, which is used to dissolve clots in patients experiencing heart attacks, or arterial/pulmonary embolisms. Streptokinase works through enabling cleavage of the Arg/Val bond in plasminogen, so that plasmin is formed which breaks down fibrin matrix in the thrombus which in turn creates thrombolytic action. Streptokinase activates plasminogen. Then zooming in even further to the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide uses vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase. This enzyme also catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin, and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced, which then uses fibrinogen alpha, beta, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator through plasminogen, which is activated by streptokinase and creates fibrin degradation products. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa.  From there, this protein complex is catalyzed into prothrombinase complex, the group of proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Tenecteplase Action Pathway?,"Tenecteplase is an enzyme that is part of the thrombolytics drug class, used to dissolve or break down blood clots. Tenecteplase activates plasminogen. Then zooming in even further to the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide uses vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase. This enzyme also catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin, and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced, which then uses fibrinogen alpha, beta, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator (tenecteplase) through plasminogen,  and creates fibrin degradation products. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa.  From there, this protein complex is catalyzed into prothrombinase complex, the group of proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Urokinase Action Pathway?,"Urokinase is an enzyme that is part of the thrombolytics drug class, used to dissolve or break down blood clots. Urokinase activates plasminogen. Then zooming in even further to the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide uses vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase. This enzyme also catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin, and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced, which then uses fibrinogen alpha, beta, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator (urokinase) through plasminogen,  and creates fibrin degradation products. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa.  From there, this protein complex is catalyzed into prothrombinase complex, the group of proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Reteplase Action Pathway?,"Reteplase is an enzyme that is part of the thrombolytics drug class, used to dissolve or break down blood clots. Reteplase activates plasminogen. Then zooming in even further to the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide uses vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase. This enzyme also catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin, and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced, which then uses fibrinogen alpha, beta, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator (reteplase) through plasminogen,  and creates fibrin degradation products. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa.  From there, this protein complex is catalyzed into prothrombinase complex, the group of proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Aminocaproic Acid Action Pathway?,"Aminocaproic acid, brand name Amicar, is a derivate of lysine and is an antifibrinolytic drug. Antifibrinolytics drugs are commonly used during major surgery to prevent significant blood loss. These drugs reversibly blocks the binding sites on plasminogen. This blockade inhibits plasminogen binding to fibrin and the conversion of plasminogen to plasmin. These prevents fibrin degradation and maintains the stability of fibrin clots. "
What is the definition of Tranexamic Acid Action Pathway?,"Tranexamic acid is a synthetic version of an amino acid found in the body called lysine that plays a role in antifibrinolytic processes. It is used to stop bleeding and hemorrhaging in patients. Tranexamic acid works by inhibiting the activation of plasminogen, which reduces the amount of plasmin that can be produced, thereby slowing the amount of clot degradation that can occur. Tranexamic acid inhibits plasminogen. Then zooming in even further to the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide uses vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase. This enzyme also catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin, and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced, which then uses fibrinogen alpha, beta, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator through plasminogen, at which point tranexamic acid inhibits plasminogen which does not allow fibrin degradation products to be created as a result. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa.  From there, this protein complex is catalyzed into prothrombinase complex, the group of proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Aprotinin Action Pathway?,"Aprotinin, trade name Trasylol is a bovine serine protease inhibitor of trypsin, chymotrypsin, kallikrein and plasmin. Aprotinin is administered prophylactically to patients undergoing surgery with a high risk of bleeding to block fibrinolysis and prevent the breakdown of blood clots. The inhibition of kallikrein inhibits factor XIIa production to reduce fibrinolysis and coagulation. Inhibition of plasmin slows down fibrinolysis. Hypersensitivity reactions may occur after repeat exposure to Aprotinin. "
What is the definition of Warfarin Action Pathway?,"Warfarin is a drug part of the anticoagulant drug class, used to dissolve or break down blood clots. Warfarin inhibits vitamin K epoxide reductase complex subunit 1. In the endoplasmic reticulum within the liver, vitamin K1 2,3-epoxide would regularly use vitamin K epoxide reductase complex subunit 1 to become reduced vitamin K (phylloquinone), and then back to vitamin K1 2,3-epoxide continually through vitamin K-dependent gamma-carboxylase, but as warfarin inhibits vitamin K epoxide reductase complex subunit 1, this causes a decreased amount of the reduced form of vitamin K, which in turn causes a decreased coagulability of the blood. The enzyme vitamin K-dependent gamma carboxylase catalyzes precursors of prothrombin and coagulation factors VII, IX and X to prothrombin, and coagulation factors VII, IX and X. From there, these precursors and factors leave the liver cell and enter into the blood capillary bed. Once there, prothrombin is catalyzed into the protein complex prothrombinase complex which is made up of coagulation factor Xa/coagulation factor Va (platelet factor 3). These factors are joined by coagulation factor V. Through the two factors coagulation factor Xa and coagulation factor Va, thrombin is produced, which then uses fibrinogen alpha, beta, and gamma chains to create fibrin (loose). This is then turned into coagulation factor XIIIa, which is activated through coagulation factor XIII A and B chains. From here, fibrin (mesh) is produced which interacts with endothelial cells to cause coagulation. Plasmin is then created from fibrin (mesh), then joined by tissue-type plasminogen activator (reteplase) through plasminogen,  and creates fibrin degradation products. These are enzymes that stay in your blood after your body has dissolved a blood clot. Coming back to the factors transported from the liver, coagulation factor X is catalyzed into a group of enzymes called the tenase complex: coagulation factor IX and coagulation factor VIIIa (platelet factor 3). This protein complex is also contributed to by coagulation factor VIII, which through prothrombin is catalyzed into coagulation factor VIIIa.  From there, this protein complex is catalyzed into prothrombinase complex, the group of proteins mentioned above, contributing to the above process ending in fibrin degradation products. Another enzyme transported from the liver is coagulation factor IX which becomes coagulation factor IXa, part of the tense complex, through coagulation factor XIa. Coagulation factor XIa is produced through coagulation factor XIIa which converts coagulation XI to become coagulation factor XIa. Coagulation factor XIIa is introduced through chain of activation starting in the endothelial cell with collagen alpha-1 (I) chain, which paired with coagulation factor XII activates coagulation factor XIIa. It is also activated through plasma prekallikrein and coagulation factor XIIa which activate plasma kallikrein, which then pairs with coagulation factor XII simultaneously with the previous collagen chain pairing to activate coagulation XIIa. Lastly, the previously transported coagulation factor VII and tissue factor coming from a vascular injury work together to activate tissue factor: coagulation factor VIIa. This enzyme helps coagulation factor X catalyze into coagulation factor Xa, to contribute to the prothrombinase complex and complete the pathway."
What is the definition of Acenocoumarol Action Pathway?,"Acenocoumarol (also known as Nitrowarfarin or Sinthrome) is an anticoagulant that inhibit the liver enzyme vitamin K reductase, which cause Vitamin K1 2,3-epoxide could not be catalyzed by vitamin K reductase to form vitamin KH2, the reduced form of vitamin K. Vitamin K-dependent coagulation factors (II, VII, IX, and X) requires its cofactor, vitamin K to facilitate the activation and gamma-carboxylation. Inhibition of vitamin K reductase results in reduced concentration of vitamin KH2, which will ultimately lead to decreased coagulability of the blood and reduced cleavage of fibrinogen into fibrin."
What is the definition of Dicumarol Action Pathway?,"Dicumarol (also known as bishydroxycoumarin) is an anticoagulant that inhibit the liver enzyme vitamin K reductase, which cause Vitamin K1 2,3-epoxide could not be catalyzed by vitamin K reductase to form vitamin KH2, the reduced form of vitamin K. Vitamin K-dependent coagulation factors (II, VII, IX, and X) requires its cofactor, vitamin K to facilitate the activation and gamma-carboxylation. Inhibition of vitamin K reductase results in reduced concentration of vitamin KH2, which will ultimately lead to decreased coagulability of the blood and reduced cleavage of fibrinogen into fibrin."
What is the definition of Phenprocoumon Action Pathway?,"Phenprocoumon is an anticoagulant that inhibits the liver enzyme vitamin K reductase. This leads to the depletion of the reduced form of vitamin K (vitamin KH2). As vitamin K is a cofactor for the gamma-carboxylation and subsequent activation of the vitamin K-dependent coagulation factors (II, VII, IX, and X), this ultimately results in reduced cleavage of fibrinogen into fibrin and decreased coagulability of the blood."
What is the definition of Esomeprazole Action Pathway?,"Esomeprazole is a compound that inhibits gastric acid secretion and is indicated in the treatment of gastroesophageal reflux disease (GERD), the healing of erosive esophagitis, and H. pylori eradication to reduce the risk of duodenal ulcer recurrence. Esomeprazole belongs to a new class of antisecretory compounds, the substituted benzimidazoles, that do not exhibit anticholinergic or H2 histamine antagonistic properties, but that suppress gastric acid secretion by specific inhibition of the H+/K+ ATPase enzyme system at the secretory surface of the gastric parietal cell. Because this enzyme system is regarded as the acid (proton) pump within the gastric mucosa, Esomeprazole has been characterized as a gastric acid-pump inhibitor, in that it blocks the final step of acid production. This effect is dose-related and leads to inhibition of both basal and stimulated acid secretion irrespective of the stimulus."
What is the definition of Omeprazole Action Pathway?,"Omeprazole is a compound that inhibits gastric acid secretion and is indicated in the treatment of gastroesophageal reflux disease (GERD), the healing of erosive esophagitis, and H. pylori eradication to reduce the risk of duodenal ulcer recurrence. Omeprazole belongs to a new class of antisecretory compounds, the substituted benzimidazoles, that do not exhibit anticholinergic or H2 histamine antagonistic properties, but that suppress gastric acid secretion by specific inhibition of the H+/K+ ATPase enzyme system at the secretory surface of the gastric parietal cell. Because this enzyme system is regarded as the acid (proton) pump within the gastric mucosa, omeprazole has been characterized as a gastric acid-pump inhibitor, in that it blocks the final step of acid production. This effect is dose-related and leads to inhibition of both basal and stimulated acid secretion irrespective of the stimulus."
What is the definition of Lansoprazole Action Pathway?,"Lansoprazole belongs to a class of antisecretory compounds, the substituted benzimidazoles, that do not exhibit anticholinergic or histamine H2-receptor antagonist properties, but rather suppress gastric acid secretion by specific inhibition of the (H+,K+)-ATPase enzyme system at the secretory surface of the gastric parietal cell. Because this enzyme system is regarded as the acid (proton) pump within the parietal cell, Lansoprazole has been characterized as a gastric acid-pump inhibitor, in that it blocks the final step of acid production. This effect is dose-related and leads to inhibition of both basal and stimulated gastric acid secretion irrespective of the stimulus."
What is the definition of Pantoprazole Action Pathway?,"Pantoprazole is a proton pump inhibitor (PPI) that suppresses the final step in gastric acid production by forming a covalent bond to two sites of the (H+,K+ )- ATPase enzyme system at the secretory surface of the gastric parietal cell. This effect is dose-related and leads to inhibition of both basal and stimulated gastric acid secretion irrespective of the stimulus."
What is the definition of Rabeprazole Action Pathway?,"Rabeprazole is a drug that belongs to the anti secretory drug class. It is used as an anti-ulcer medication, and helps relieve gastric acid reflux, gastric irritation and gastric pain. It inhibits the proton pump action of ATPase, which blocks the final step of gastric acid secretion. The pathway begins in the parietal cell in the stomach, where rabeprazole and a hydrogen ion use the active metabolite in rabeprazole —rabeprazole thioether — to inhibit potassium-transporting ATPase at the secretory surface of the gastric parietal cell. Now in the gastric endothelial cell, these secretory surfaces are inhibited by rabeprazole and by G-Protein signalling cascade through somatostatin receptor type 4, which is activated by somatostatin. At the same time, potassium-transporting ATPase is activated by the G-protein signalling cascade, through histamine H2 receptor, gastrin/cholecystokinin type B receptor, and muscarinic acetylcholine receptor M3 which are activated by histamine, gastrin and acetylcholine, respectively. The potassium transporting ATPase also converts water and ATP to a phosphate molecule and ADP. Alongside the transporters, potassium is brought into the cell. Carbonic anhydrase 1 uses water and carbon dioxide to create hydrogen carbonate and a hydrogen ion, which are both transported out of the endothelial cell, into the gastric lumen. A chloride ion is transported into the gastric endothelial cell through a chloride anion exchanger and is transported out of the cell through a chloride intracellular channel protein 2, back into the gastric lumen."
What is the definition of Ranitidine Action Pathway?,"Ranitidine is an anti-ulcer agent, that works through antagonizing the histamine H2 receptor. It is used to reduce abdominal pain, heartburn, acid indigestion and acid reflux. The pathway begins in the stomach, where ranitidine inhibits the histamine H2 receptor on the surface of the parietal cell. Now in the gastric endothelial cell, potassium-transporting ATPase units are inhibited by G-Protein signalling cascade through somatostatin receptor type 4, which is activated by somatostatin. At the same time, potassium-transporting ATPase is activated by the G-protein signalling cascade, through histamine H2 receptor which is inhibited by ranitidine, gastrin/cholecystokinin type B receptor, and muscarinic acetylcholine receptor M3 which are activated by histamine, gastrin and acetylcholine, respectively. The potassium transporting ATPase also converts water and ATP to a phosphate molecule and ADP. Alongside the transporters, potassium is brought into the cell. Carbonic anhydrase 1 uses water and carbon dioxide to create hydrogen carbonate and a hydrogen ion, which are both transported out of the endothelial cell, into the gastric lumen. A chloride ion is transported into the gastric endothelial cell through a chloride anion exchanger and is transported out of the cell through a chloride intracellular channel protein 2, back into the gastric lumen."
What is the definition of Famotidine Action Pathway?,"Famotidine (also known as Pepcid) can bind and inhibit histamine H2 receptor on parietal cell's basolateral membrane. Binding of famotidine can effectively inhibit the histamine effects, which lead to reduced nocturnal gastric acid and basal secretion; it can also decrease gastric volume, gastric acid and acidity. "
What is the definition of Cimetidine Action Pathway?,"Cimetidine binds to histamine H2-receptors located on the basolateral membrane of the gastric parietal cell, blocking histamine effects. This competitive inhibition results in reduced gastric acid secretion and a reduction in gastric volume and acidity."
What is the definition of Nizatidine Action Pathway?,"Nizatidine (also known as Axid or Acinon) is a histamine H2 receptor antagonist, that can bind to histamine H2 receptor on gastric basolateral membrane, which can reduce the gastric acid response. Blocking of histamine binding to histamine H2 receptor can reduce the secretion of nocturnal and basal gastric acid."
What is the definition of Pirenzepine Action Pathway?,"Pirenzepine (also known as Gastrozepin) is a selective antagonist (antimuscarinic) that will inhibit the muscarinic acetylcholine receptor M3 inside the stomach. Binding of pirenzepine on the receptor will decrease the level of exertion of gastric acid secretion, and also it can reduce muscle spasms. Therefore, pirenzipine can be used for treating peptic ulcers, prevent motion sickness, vomiting and nausea."
What is the definition of Chlorothiazide Action Pathway?,"Chlorothiazide (also known as Diuril) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Polythiazide Action Pathway?,"Polythiazide (also known as Renese or Drenusil) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Methyclothiazide Action Pathway?,"Methyclothiazide (also known as Enduron or Methyclothiazid) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Bumetanide Action Pathway?,"Bumetanide, trade name Bumex, is a loop diuretic that increases urine production by inhibiting the reabsorption of water in the nephron. In the thick ascending limb of the loop of Henle, the sodium-potassium-chloride cotransporter (NKCC2) is competitively inhibited at the chloride binding site blocking sodium transport from the lumen to the interstitium. This results in the lumen becoming hypertonic and a decreased osmotic gradient thereby reducing the water reabsorption. In the nephron, the think ascending limb reabsorbs 25% of sodium and is a good target for diuretics. "
What is the definition of Bendroflumethiazide Action Pathway?,"Bendroflumethiazide (also known as  bendrofluazide (BAN) or Aprinox) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Quinethazone Action Pathway?,"Quinethazone, also known under the brand-name Hydromox, is a pharmacologically-active small molecule that belongs to a class of drugs called thiazides. Thiazides and thiazide-like drugs are diuretics commonly employed to control hypertension. The short term mechanism of action is relatively well-understood: thiazides inhibit sodium-chloride co-transport into the renal distal convoluted tubule of the nephron and therefore increase fluid loss which decreases extracellular fluid (ECF), plasma volume, and ultimately blood pressure. In the case of quinethazone, it inhibits the sodium-chloride symporter, solute carrier family 12 member 3. Thiazides also inhibit sodium ion transport. However, the long-term mechanism of action isn’t as well-characterized and it is thought that other processes beyond regulating plasma and ECF volumes are involved as these two volumes return to baseline within 4-6 weeks of first use of thiazides."
What is the definition of Ethacrynic Acid Action Pathway?,"Etacrynic acid (also known as ethacrynic acid and Edecrin) is a loop diuretic that can inhibit water reabsorption by binding and inhibiting solute carrier family 12 member 1 (also known as sodium-potassium-chloride cotransporter) in the loop of Henle. Binding of the transporter can prevent import of sodium from lumen from loop of Henle to basolateral interstitium, which lead to more hypertonic environment in lumen than interstitium, and result in prevention of water reabsorption due to diminished osmotic gradient in nephron.  "
What is the definition of Hydrochlorothiazide Action Pathway?,"Hydroflumethiazide (also known as Esidrix or Oretic) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Cyclothiazide Action Pathway?,"Cyclothiazide (also known as Anhydron or Acquirel) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption."
What is the definition of Metolazone Action Pathway?,"Metolazone (also known as Zytanix, Zaroxolyn or Mykrox) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Hydroflumethiazide Action Pathway?,"Hydroflumethiazide (also known as Saluron or Diuredemina) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Indapamide Action Pathway?,"Indapamide (also named as Noranat or Veroxil) is a thiazide-like diuretic drug that can be used to treat hypertension and decompensated heart failure. Indapamide can inhibit sodium-chloride symporter in distal convoluted tubule to prevent sodium reabsorption (5% of total sodium reabsorption), so that the osmotic gradient is decreased which lead to reduced water reabsorption or totally inhibition of water reabsorption in nephron. Sodium-chloride symporter (also known as solute carrier family 12 member 3) can translocate chloride and sodium from lumen to epithelial cell. Sodium-potassium ATPase can export sodium from cell to basolateral interstitium, which lead to increased osmolarity in interstitum for later water reabsorption. "
What is the definition of Furosemide Action Pathway?,"Furosemide (also named Lasix) is a medication that can be used for high blood pressure and fluid build-up which caused by heart failure, liver scarring, or kidney disease. Furosemide can bind and inhibit sodium-potassium-chloride cotransporter (NKCC2/SLC22A1) to prevent the water reabsorption in nephron. Inhibition of sodium-potassium-chloride cotransporter can prevent transportation of sodium from lumen to basolateral interstitium, which lead to more hypertonic in lumen and less hypertonic in basolateral interstitium that will allow water reabsorption through nephron. "
What is the definition of Torsemide Action Pathway?,"Torsemide, also known as torasemide is a pharmacologically-active small molecule that belongs to the drug class of loop diuretics. It is commonly used to manage hypertension and  edema in cases of congestive heart failure as it acts as a diuretic by blocking sodium transporters NKCC2 on the thick ascending limb of the Loop of Henle in the renal tissues. Specifically it acts on solute carrier family 12 member 1. This prevents the reuptake of sodium into the Loop of Henle which consequentially reduces the uptake of water and serves to both increase water loss and reduce blood pressure. Torsemide appears to reduce blood pressure beyond its action in reducing salt uptake in the Loop of Henle; it also seems to be involved in reducing vasoconstriction by blocking the action of angiotensin II."
What is the definition of Trichlormethiazide Action Pathway?,"Trichlormethiazide is a pharmacologically-active small molecule that belongs to a class of drugs called thiazides. Thiazides and thiazide-like drugs are diuretics commonly employed to control hypertension. Trichloromethiazide acts by inhibiting chloride and potentially sodium reabsorption in the ascending loop of Henle, specifically at solute carrier family 12 member 3. This action results in increased fluid loss which ultimately reduces blood volume and pressure. Trichlormethiazide also acts to inhibit sodium uptake and increase potassium excretion which also serves to increase fluid loss. The long-term antihypertensive effects of thiazides and thiazide-like drugs such as trichlormethiazide are not well-characterized but may involve its action on carbonic anhydrases."
What is the definition of Chlorthalidone Action Pathway?,"Chlorthalidone (also known as chlorthalidone or phthalamudine) is an organic compound that used for diuretic. It can inhibit the solute carrier family 12 member 3 (also known as sodium-chloride symporter) in the nephron to prevent water reabsorption. Solute carrier family 12 member 3 is also used for sodium reabsorption that count for 5% of total amount. Solute carrier family 12 member 3 transports chloride and sodium from lumen to epithelial cell, and sodium/potassium ATPases facilitate the export of sodium to basolateral interstitium to provide sodium gradient that will increase the osmolarity in interstitium, which lead to establishment of osmotic gradient for water reabsorption. "
What is the definition of Triamterene Action Pathway?,"Triamterene is a diuretic that belongs to the potassium-sparing class of drugs which are commonly used to manage hypertension and edema. It acts by blocking epithelial sodium channels in the late distal convoluted tubule of the nephron. Specifically, triamterene inhibits amiloride-sensitive sodium channels which are responsible for the reabsorption of sodium in the late distal convoluted tubule in the nephron. This primarily contributes to an increase in sodium excretion and consequentially, fluid excretion which decreases blood volume and blood pressure. Potassium secretion is indirectly affected by the inhibition of sodium reabsorption due to the elimination of the electrochemical gradient that drives potassium loss. This leads to an increase in serum potassium concentration -- a common action for potassium-sparing drugs -- and has the potential to induce hyperkalemia which can potentially lead to severe heart arrhythmias. "
What is the definition of Amiloride Action Pathway?,"Amiloride is a diuretic that inhibits the sodium channels in the late distal convoluted tubule and collecting tube of the nephron where 1-2% of sodium reabsorption occurs. The inhibition of sodium reabsorption results in increased osmolarity in the lumen and decreased osmolarity in the interstitium of the nephron. This decreased osmotic gradient results in a modest diuresis. The drug is also potassium sparing. Potassium is typically excreted due to the electrochemical gradient produced by sodium reabsorption. Therefore, amiloride's inhibition of sodium reabsorption fails to produce an electrochemical gradient and therefore, inhibits potassium excretion. Amiloride causes an increase in sodium excretion and a decrease in potassium secretion. The drug is typically prescribed to patients with depleted potassium. "
What is the definition of Spironolactone Action Pathway?,"Spironolactone is a potassium-sparing diuretic. It acts by competing with aldosterone for its receptor inside the principal cells of the late distal tubule and collecting tubule. Aldosterone increases sodium reabsorption and potassium excretion by up-regulating the expression of basolateral sodium-potassium ATPases as well as luminal (apical) sodium and potassium channels. Sodium in the nephron lumen enters the principal cells through the luminal sodium channels, where it is then actively pumped out into the interstitium by sodium-potassium ATPases. This causes the interstitium to become hyperosmotic and establishes an osmotic gradient, facilitating water reabsorption through aquaporin channels. On the other hand, potassium is actively pumped from the interstitium into the principle cell. It then diffuses from inside the cell into the nephron lumen via potassium channel, driven by an electrochemical gradient established by sodium leaving the lumen. Potassium entering the nephron lumen is subsequently excreted in the urine. Spironolactone inhibits sodium and water reabsorption as well as potassium excretion by blocking the actions of aldosterone as described above."
What is the definition of Eplerenone Action Pathway?,"Eplerenone is a potassium-sparing diuretic. It acts by competing with aldosterone for its receptor inside the principal cells of the late distal tubule and collecting tubule. Aldosterone increases sodium reabsorption and potassium excretion by up-regulating the expression of basolateral sodium-potassium ATPases as well as luminal (apical) sodium and potassium channels. Sodium in the nephron lumen enters the principal cells through the luminal sodium channels, where it is then actively pumped out into the interstitium by sodium-potassium ATPases. This causes the interstitium to become hyperosmotic and establishes an osmotic gradient, facilitating water reabsorption through aquaporin channels. On the other hand, potassium is actively pumped from the interstitium into the principle cell. It then diffuses from inside the cell into the nephron lumen via potassium channel, driven by an electrochemical gradient established by sodium leaving the lumen. Potassium entering the nephron lumen is subsequently excreted in the urine. Eplerenone inhibits sodium and water reabsorption as well as potassium excretion by blocking the actions of aldosterone as described above."
What is the definition of Azithromycin Action Pathway?,"Azithromycin, trade names include Zithromax and Azithrocin, is a semisynthetic azalide derived from erythromycin. Azalides are part of the macrolide antibiotic class. Azithromycin targets protein synthesis of bacteria by binding to the 50S subunit of the bacterial ribosome to inhibit mRNA translation and prevent bacteria growth. Macrolides are broad spectrum antibiotics. It is prescribed to treat bacterial infections including: sexually transmitted infections like chlamydia, pneumonia, strep throat, ear infections, sinusitis and more. "
What is the definition of Clarithromycin Action Pathway?,"Clarithromycin, a semisynthetic macrolide antibiotic derived from erythromycin, is active against a wide range of microorganisms. Clarithromycin inhibits protein synthesis in bacteria by reversibly binding to the 50S ribosomal subunits. This inhibits the translocation of aminoacyl transfer-RNA and prevents peptide chain elongation. Clarithromycin is effective against Mycobacterium avium complex (MAC) and is used for the treatment of Helicobacter pylori-associated peptic ulcer disease, community-acquired pneumonia, sinusitis, and chronic bronchitis. Clarithromycin is also used to treat respiratory tract, sexually transmitted, otitis media, and AIDS-related infections. Clarithromycin is first metabolized to 14-OH clarithromycin. Like other macrolides, it then binds to the 50S subunit of the 70S ribosome of the bacteria, blocking RNA-mediated bacterial protein synthesis. Clarithromycin also inhibits the hepatic microsomal CYP3A4 isoenzyme and P-glycoprotein, an energy-dependent drug efflux pump. "
What is the definition of Clindamycin Action Pathway?,"Clindamycin is a natural antibiotic that produced by Streptomyces lincolnensis, which can be used for treating various bacterial infections by binding and inhibiting 23S portion of 50S subunit of ribosomes. Blocking the portion of ribosome can prevent transpeptidase reaction that will elongate peptide chain. Clindamycin has a bacteriostatic effect. It is used primarily to treat infections caused by susceptible anaerobic bacteria, including infections of the respiratory tract, skin and soft tissue infections, and peritonitis. In patients with hypersensitivity to penicillins, clindamycin may be used to treat infections caused by susceptible aerobic bacteria as well. Clindamycin may also be used in combination with chloroquine and quinine to treat malaria caused by Pasmodium falciparum. It is commonly used as a topical treatment for acne, and can be useful against some methicillin-resistant Staphylococcus aureus (MRSA) infections. Clindamycin may also be used to treat bone and joint infections, particularly those caused by Staphylococcus aureu"
What is the definition of Erythromycin Action Pathway?,"Erythromycin is a bacteriostatic macrolide antibiotic antibiotic that can be used for treating various bacterial infections by inhibiting the bacterial protein synthesis. Erythromycin is produced from Streptomyces erythreus. Erythromycin can bind to 50S ribosomal subunits near the donor site reversibly. Blocking tRNA can prevent the translocation of peptides, which lead to inhibition of bacterial protein synthesis. "
What is the definition of Roxithromycin Action Pathway?,"A member of the semi-synthetic macrolide class of antibiotics, roxithromycin is employed in infections of the respiratory tract, urinary, and soft tissue infections. Its macrocyclic lactone ring and deoxy sugars, defining features of macrolide antibiotics, mediates its mechanism of action as it inhibits peptide translocation by binding to the 50S subunit of the bacterial ribosome. Protein synthesis is thus inhibited by ribosomal binding. It has been demonstrated to have a longer half-life compared to other macrolide antibiotics such as erythromycin and is effective against certain Gram-negative bacteria."
What is the definition of Telithromycin Action Pathway?,"Telithromycin is a semi-synthetic erythromycin derivative. It belongs to the chemical family called ketolides, a group belonging to the macrolide-lincosamide-streptogramin (MLS) class. Telithromycin prevents bacterial growth by inhibiting bacterial protein synthesis. Similar to macrolides, telithromycin directly blocks translation of the bacterial 23S ribosomal RNA; however, unlike macrolides, telithromycin also blocks bacterial ribosomal assembly (mechanism not shown). Telithromycin binds to two sites on the 50S ribosomal subunit, domains II and V of the 23S rRNA, whereas macrolides bind only to domain V. The C11-12 carbamate side chain is thought to contribute to a higher binding affinity of telithromycin compared to erythromycin A. In erythromycin A-susceptible bacteria, telithromycin exhibits 10 times greater affinity than erythromycin. Its relative binding affinity is further increased to 25 times greater in macrolide-resistant bacteria strains. This is likely due to the additional binding site on domain II since macrolide resistance occurs as a result of alterations in the domain V binding site. "
What is the definition of Amikacin Action Pathway?,"Amikacin is an aminoglycoside antibiotic that inhibits bacterial protein synthesis. Amikacin binds irreversibly to the bacterial 30S ribosomal subunit protein and 16S rRNA and prevents the formation of the initiation complex with messenger RNA. More specifically, amikacin binds four nucleotides of the 16S rRNA and a single amino acid of protein S12. This interferes with the decoding site in the vicinity of nucleotide 1400 in 16S rRNA of the 30S subunit. This region interacts with the wobble base of the anticodon of tRNA. This leads to interference with the initiation complex, misreading of mRNA so that incorrect amino acids are inserted into the polypeptide leading to nonfunctional or toxic peptides, and the breakup of polysomes into nonfunctional monosomes. Aminoglycosides are useful in treating infections from mycobacteria such as, tuberculosis, and aerobic Gram-negative bacteria including, Pseudomonas, Acinetobacter and Enterobacter. Aminoglycosides can also treat Gram-positive bacterial infections but are inferior to other available antibiotics. Aminoglycosides may be used in combination with penicillin type antibiotics. Aminoglycosides are not an effective treatment for anaerobic bacteria, fungi and viruses. "
What is the definition of Gentamicin Action Pathway?,"Gentamicin (also known as Garamycin) is an antibiotic that can be used to treat various bacterial infections by inhibiting bacterial protein synthesis. Gentamicin can bind on bacterial 30S ribosomal subunit protein and 16S rRNA irreversibly to inhibit the formation of mRNA. Since the binding site of gentamicin is the region that interacts with wobble base of anticodon of tRNA, hence, binding will cause misreading of mRNA, which lead to incorrect insertion of amino acids to polypeptide so that the polypeptide is non-functional or toxic. This prevents the bacterial protein synthesis which prevent the growth of the bacteria. Gentamicin is a class of aminoglycosides. Aminoglycosides can effectively against aerobic, Gram-negative bacteria, but it is ineffective against anaerobic bacteria, fungi and viruses."
What is the definition of Kanamycin Action Pathway?,"Kanamycin is an aminoglycoside antibiotic that can used for inhibiting protein synthesis of bacteria, which can be used for treating bacterial infections and tuberculosis. Kanamycin can bind to bacterial 30S ribosomal subunit protein and four nucleotides of 16S rRNA irreversibly to inhibit the formation of mRNA. Binding of kanamycin can interfere the vicinity of nucleotide 1400 in 16S rRNA that can interact with wobble base of the anticodon of tRNA, which lead to misreading of mRNA and wrong insertion of amino acids. The result is the nonfunctional or toxic peptides that is generated from the ribosome. Aminoglycosides can be used for treating bacterial infections from aerobic, Gram-negative bacteria and also Gram-postive bacteria. However, aminoglycosides may cause more damage to the host than other antibiotics for Gram-positive bacterial infection. Aminoglycosides are mostly ineffective against anaerobic bacteria, fungi and viruses."
What is the definition of Neomycin Action Pathway?,"Neomycin is a member of the aminoglycoside family of antibiotics. As an aminoglycoside, neomycin can effectively against a wide variety of pathogenic bacteria such as E.coli, Citrobacter sp., etc. Neomycin can also effectively against Hemophilus influenzae, Salmonella sp. and others in vitro. However, netilmicin are ineffective against anaerobic bacteria, fungi and viruses. Neomycin binds irreversibly to the bacterial 30S ribosomal subunit protein and 16S rRNA and prevents the formation of the initiation complex with messenger RNA. More specifically, neomycin binds four nucleotides of the 16S rRNA and a single amino acid of protein S12. This interferes with the decoding site in the vicinity of nucleotide 1400 in 16S rRNA of the 30S subunit. This region interacts with the wobble base of the anticodon of tRNA. Binding of netilmicin can cause misreading of mRNA which result in insertion of incorrect amino acids to polypeptide. This lead to nonfunctional or toxic peptides of protein complex."
What is the definition of Netilmicin Action Pathway?,"Netilmicin is a member of the aminoglycoside family of antibiotics that is produced by fermentation of Micromonospora inyoensis. Netilmicin can effectively against a wide variety of pathogenic bacteria such as E.coli, Citrobacter sp., etc. Netilmicin can also effectively against Hemophilus influenzae, Salmonella sp. and others in vitro. However, netilmicin are ineffective against anaerobic bacteria, fungi and viruses. Netilmicin binds irreversibly to the bacterial 30S ribosomal subunit protein and 16S rRNA and prevents the formation of the initiation complex with messenger RNA. Binding of netilmicin can cause misreading of mRNA which result in insertion of incorrect amino acids to polypeptide. This lead to nonfunctional or toxic peptides of protein complex."
What is the definition of Spectinomycin Action Pathway?,"Spectinomycin (also named Togamycin or Trobicin) is an aminocyclitol antibiotic for the treatment of gonorrhea infections such as penicillin-resistant Neisseria gonorrhoeae (experimental studies shows that spectinomycin equips with bacteriostatic effect against most Neisseria gonorrhoeae strains). It is produced from Streptomyces spectabilis, which is a soil microorganism. Spectinomycin reversibly interferes with the interaction between mRNA and the bacterial 30S ribosomal subunit. It is structurally similar to aminoglycosides, but does not cause misreading of mRNA. It is structurally similar to aminoglycosides, but does not cause misreading of mRNA. "
What is the definition of Streptomycin Action Pathway?,"Streptomycin (also named Gerox or Agrimycin) is an aminoglycoside antibiotic for the treatment of bacteria infections by inhibiting the synthesis of bacterial proteins. Streptomycin reversibly binds to 16S rRNA and the bacterial 30S ribosomal subunit so that the initiation complex with mRNA couldn't be formed. Binding of streptomycin on 16S rRNA's four nocleotides will lead to misreading of mRNA which result in insertion of incorrect amino acids into polypeptide. Nonfunctional or toxic peptides will lead to nonfunctional monosomes. Aminoglycosides are useful primarily in infections involving aerobic, Gram-negative bacteria, such as Pseudomonas, Acinetobacter, and Enterobacter. In addition, some mycobacteria, including the bacteria that cause tuberculosis, are susceptible to aminoglycosides. Infections caused by Gram-positive bacteria can also be treated with aminoglycosides, but other types of antibiotics are more potent and less damaging to the host. In the past the aminoglycosides have been used in conjunction with penicillin-related antibiotics in streptococcal infections for their synergistic effects, particularly in endocarditis. Aminoglycosides are mostly ineffective against anaerobic bacteria, fungi and viruses."
What is the definition of Demeclocycline Action Pathway?,"Demeclocycline is a tetracycline antibiotic that inhibits bacterial cell growth by inhibiting translation. It is lipophilic and can easily pass through cell membranes or passively diffuse through porin channels in bacterial membranes. Demeclocycline is bacteriostatic; it impairs bacterial growth but does not kill bacterial directly. Demeclocycline reversibly binds to the bacterial 30S and to a lesser extent the 50S ribosomal subunits. Binding prevents the amino-acyl tRNA from binding to the A site of the ribosome complex, which subsequently impairs protein synthesis. Demeclocycline may be used against susceptible strains of Rickettsiae (e.g. Rocky Mountain spotted fever, typhus fever, Q fever, rickettsial pox and Brill-Zinsser disease), Chlamydiae (psittacosis, lymphogranuloma venereum, uncomplicated sexually transmitted infections), Mycoplasma pneumoniae (PPLO, Eaton agent), Borrelia burgdorferi (Lyme disease), and some uncommon gram-negative infections caused by Brucella sp., Bartonella sp., Calymmatobacterium granulomatis, Vibrio cholera."
What is the definition of Doxycycline Action Pathway?,"Doxycycline is a long-acting tetracycline derived from oxytetracycline. Like minocycline, it is lipophilic and can diffuse through the lipid bilayer of bacteria. Doxycycline reversibly binds to the bacterial 30S ribosomal subunit and to a lesser extent the 50S subunit, blocking the binding of aminoacyl tRNA to the A site on the ribosome-RNA complex. Binding inhibits bacterial protein synthesis and hence cell growth. Doxycycline may be used to treat treat non-gonococcal urethritis and cervicitis, adult periodontitis, rosacea, inflammatory acne vulgaris and syphilis in patients allergic to penicillin. It may also be used as prophylaxis against chloroquine-resistant and/or mefloquine-resistant  P. falciparum, one of the species of malaria-causing parasites. "
What is the definition of Minocycline Action Pathway?,"Minocycline is the most acitve tetracycline antibiotic that can prevent tRNA binding to 30S ribosomal of bacteria by blocking the 30S ribosomal subunit. Its lipid-solublable property allows it can pass lipid bilayers of membrane directly. Minocycline can also pass the membrane through porin channels in bacterial membrane. Due to blocking of 30S ribosomal subunit, activity of bacterial protein synthesis will be inihibited which lead to inhitation of further growth and colonization of bacteria."
What is the definition of Oxytetracycline Action Pathway?,"Oxytetracycline, the second of the tetracyclines discovered, is a broad-spectrum antibiotic. Oxytetracycline is lipophilic and easily passes through cell membranes or enters bacterial cells via membrane porin channels. Once inside the cell, it binds to the bacterial 30S ribosomal subunit and prevents aminoacyl tRNA from binding to the A site of the ribosome-RNA complex; binding inhibition likely occurs through steric hindrance. The overall effect is inhibition of bacterial protein synthesis and hence growth. "
What is the definition of Tetracycline Action Pathway?,"Tetracycline is a short-acting antibiotic that is semi-synthetically produced from chlortetracycline, a compound derived from Streptomyces aureofaciens. Tetracycline enters bacterial cells by passively diffusing through membrane porin channels. Once inside the cell, tetracycline reversibly binds to the 30S subunit just above the binding site for aminoacyl tRNA. At its primary binding site, interactions with the sugar phosphate backbone of residues in helices 31 and 34 via hydrogen bonds with oxygen atoms and hydroxyl groups on the hydrophilic side of the tetracycline help anchor the drug in position. Salt bridge interactions between the backbone of 16S rRNA and tetracycline are mediated by a magnesium ion in the binding site. Tetracycline prevents incoming aminoacyl tRNA from binding to the A site on the ribosome-RNA complex via steric hindrance. This causes inhibition of protein synthesis and hence bacterial cell growth. "
What is the definition of Lymecycline Action Pathway?,"Lymecycline is a tetracycline antibiotic that inhibits cell growth by inhibiting translation. Lymecycline is lipophilic and can diffuse across bacterial cell membranes or travel through membrane porin channels. Once inside the bacterial cell, it reversibly binds to the bacterial 30S ribosomal subunit and prevents aminoacyl tRNA from binding to the A site of the ribosome-RNA complex; aminoacyl tRNA binding inhibition likely occurs through steric hindrance. This results in inhibition of bacterial protein synthesis and hence cell growth. "
What is the definition of Acebutolol Action Pathway?,"Acebutolol (also known as Sectral or Prent) is a selective β1 adrenergic receptor antagonist (beta blocker), which can be used for treatment of high blood pressure (hypertension) and irregular heartbeats (arrhythmias). Acebutolol also has the ability to mild intrinsic sympathomimetic activity (ISA) with effective range of dosage. Adrenaline (also known as epinephrine) can activate β1 adrenergic receptor so that the heart rate and output will be increased. Renin is a hormone that generated from kidney, which could lead to constriction of blood vessels. Beta blockers could efficiently prohibit renin release.  "
What is the definition of Alprenolol Action Pathway?,"Alprenolol (also known as alfeprol, alpheprol or alprenololum) a beta blocker (non-selective) that block beta-1 adrenergic receptor in heart. Blocking beta-1 adrenergic receptor could prevent the binding of epinephrine and norepinephrine, which could efficiently reduce blood pressure and heart rate. In the juxtaglomerular apparatus, alprenolol can also bind to beta-2 receptors to prevent the production and release of renin (also known as angiotensinogenase). Without renin, angiotensin II and aldosterone could not be produced, which ultimately prevent water retention and vasoconstriction."
What is the definition of Atenolol Action Pathway?,"Atenolol, trade name Tenormin, is a beta blocker prescribed to treat hypertension. Atenolol is a selective beta-1-adrenoceptor antagonist targeting the heart and vascular smooth muscle to inhibit sympathetic activity. Binding of atenolol inhibits the G protein signalling cascade and reduces heart rate, blood pressure, cardiac output and reflex orthostatic hypotension. Beta blockers were once the first line therapy for hypertension, however, current recommendations favour calcium channel blockers and angiotensin converting enzyme inhibitors. "
What is the definition of Betaxolol Action Pathway?,"Betaxolol (also known as Betoptic or Lokren) is a selective beta blocker that can block beta1-adrenergic receptors and beta2-adrenergic receptors. Blocking of beta1-adrenergic receptors in heart and vascular smooth muscle can lead to reduced heart rate, cardiac output, and decreased blood pressure. Blocking of beta(2)-adrenergic receptors can lead to prevention of bronchospasm."
What is the definition of Bisoprolol Action Pathway?,"Bisoprolol (also known as Zebeta) is a selective beta blocker that can block beta1-adrenergic receptors and beta2-adrenergic receptors. Blocking of beta1-adrenergic receptors in heart and vascular smooth muscle can lead to reduced heart rate, cardiac output, and decreased blood pressure. Blocking of beta(2)-adrenergic receptors can lead to prevention of bronchospasm."
What is the definition of Esmolol Action Pathway?,"Similar to other beta-blockers, esmolol blocks the agonistic effect of the sympathetic neurotransmitters by competing for receptor binding sites. Because it predominantly blocks the beta-1 receptors in cardiac tissue, it is said to be cardioselective. In general, so-called cardioselective beta-blockers are relatively cardioselective; at lower doses they block beta-1 receptors only but begin to block beta-2 receptors as the dose increases. At therapeutic dosages, esmolol does not have intrinsic sympathomimetic activity (ISA) or membrane-stabilizing (quinidine-like) activity. Antiarrhythmic activity is due to blockade of adrenergic stimulation of cardiac pacemaker potentials. In the Vaughan Williams classification of antiarrhythmics, beta-blockers are considered to be class II agents."
What is the definition of Metoprolol Action Pathway?,"Metoprolol (also known as Lopressor) is a beta blocker (non-selective) that are used for treat high blood pressure or chest pain. Metoprolol bind to beta1-adrenergic receptors in heart and vascular smooth muscle to block the binding of other adrenergic neurotransmitters such as norepinephrine, which lead to decreased blood pressure, heart rate and cardiac output. "
What is the definition of Nadolol Action Pathway?,"Nadolol (also known as Corgard or Solgol) is a beta blocker (non-selective) that are used for treat high blood pressure or chest pain. Nadolol bind to beta1-adrenergic receptors in heart and vascular smooth muscle to block the binding of other adrenergic neurotransmitters such as norepinephrine, which lead to decreased blood pressure, heart rate and cardiac output. Nadolol can also bind beta-2 adrenergic receptors in juxtaglomerular apparatus and bronchiole smooth muscle. In juxtaglomerular apparatus, nadolol can prevent the production of aldosterone and angiotensin II by inhibiting renin production, which lead to prevention of water retention and vasoconstriction. In bronchiole smooth muscle, binding of nadolol to beta-2 adrenergic receptors can also prevent vasoconstriction."
What is the definition of Oxprenolol Action Pathway?,"Oxprenolol (also known as Trasacor or Trasicor) is a beta blocker (non-selective) that are used for treat high blood pressure or chest pain. Oxprenolol bind to beta1-adrenergic receptors in heart and vascular smooth muscle to block the binding of other adrenergic neurotransmitters such as norepinephrine, which lead to decreased blood pressure, heart rate and cardiac output. Oxprenolol can also bind beta-2 adrenergic receptors in juxtaglomerular apparatus and bronchiole smooth muscle. In juxtaglomerular apparatus, oxprenolol can prevent the production of aldosterone and angiotensin II by inhibiting renin production, which lead to prevention of water retention and vasoconstriction. In bronchiole smooth muscle, binding of oxprenolol to beta-2 adrenergic receptors can also prevent vasoconstriction."
What is the definition of Penbutolol Action Pathway?,"Penbutolol (also known as Levatol or Levatolol) is a beta blocker (non-selective) that are used for treat high blood pressure or chest pain. Penbutolol bind to beta1-adrenergic receptors in heart and vascular smooth muscle to block the binding of other adrenergic neurotransmitters such as norepinephrine, which lead to decreased blood pressure, heart rate and cardiac output. Penbutolol can also bind beta-2 adrenergic receptors in juxtaglomerular apparatus and bronchiole smooth muscle. In juxtaglomerular apparatus, penbutolol can prevent the production of aldosterone and angiotensin II by inhibiting renin production, which lead to prevention of water retention and vasoconstriction. In bronchiole smooth muscle, binding of penbutolol to beta-2 adrenergic receptors can also prevent vasoconstriction."
What is the definition of Pindolol Action Pathway?,"Pindolol (also known as Visken) a beta blocker (non-selective) that block beta-1 adrenergic receptor in heart. Blocking beta-1 adrenergic receptor could prevent the binding of epinephrine and norepinephrine, which could efficiently reduce blood pressure and heart rate. In the juxtaglomerular apparatus, pindolol can also bind to beta-2 receptors to prevent the production and release of renin (also known as angiotensinogenase). Without renin, angiotensin II and aldosterone could not be produced, which ultimately prevent water retention and vasoconstriction."
What is the definition of Propranolol Action Pathway?,"Propranolol, a non-cardioselective beta blocker, inhibits sympathetic stimulation by competing with neurotransmitters like catecholamines to bind beta(1)-adrenergic receptors of the heart and vascular smooth muscle. Propranolol binding reduces resting heart rate, cardiac output, blood pressure and orthostatic hypotension. Propranolol also reduce sympathetic activity to manage hyperthyroidism, anxiety and tremor. Propranolol also competes for beta(2)-adrenergic receptors on bronchial and vascular smooth muscles."
What is the definition of Quinidine Action Pathway?,"This pathway illustrates the quinidine targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cells’ extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Quinidine, a diastereomer of quinine, is a Class 1A antiarrhythmic drug that is isolated from the bark of the Cinchona plant or other related species. This alkaloid dampens the excitability of cardiac and skeletal muscles by blocking sodium and potassium currents across cellular membranes. At low concentrations, it blocks the voltage-gated sodium (I-Na) and rapid delayed rectifying potassium (I-Kr) channels. I-Na is responsible for the rapid upstroke in cell membrane potential observed on the cardiac myocyte action potential. I-Kr is partially responsible for the final repolarization phase of the action potential. By blocking I-Na, quinidine increases the threshold of excitability and decreases automaticity. I-Kr block results in action potential prolongation. At higher concentrations, quinidine also blocks voltage-gated delayed rectifying potassium channel (I-Ks), inward rectifier potassium channel (I-K1), voltage-gated transient outward delayed rectifying potassium channel (I-Kto), and L-type calcium channels (I-CaL). Quinidine also exerts antimuscarinic effects, which increase AV nodal conduction and antagonize alpha-adrenergic effects. Quinidine may be used to maintain sinus rhythm in atrial fibrillation or flutter and prevent recurrence of ventricular fibrillation or tachycardia. The side effects of quinidine include diarrhea and on rare occasions (2-8%) Torsades de Pointes. "
What is the definition of Procainamide (Antiarrhythmic) Action Pathway?,"This pathway illustrates the procainamide targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cells’ extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Procainamide, an analogue of the local anesthetic procaine, is a Class 1A antiarrhythmic drug. It has similar effects to quinidine, but lacks the antimuscarinic and antiadrenergic effects of quinidine. Like other Class 1A drugs, procainamide blocks open sodium channels leading to an increased threshold of excitability. Voltage-gated sodium channels (I-Na) are responsible for the rapid depolarization seen during cardiac contractile cell action potentials. I-Na block results in delayed excitability of the cells. Procainamide also prolongs action potential duration, likely by slowing the final repolarization phase via potassium channel blocking. This drug may be administered intravenously to treat supraventricular and ventricular arrhythmias. It is better tolerated intravenously than quinidine. Oral administration is poorly tolerated long term. "
What is the definition of Disopyramide Action Pathway?,"This pathway illustrates the disopyramide targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cells’ extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Disopyramide is a Class 1A antiarrhythmic drug with similar electrophysiological effects as quinidine. Disopyramide blocks sodium channels in their open state leading to an increased threshold of excitability. Voltage-gated sodium channels (I-Na) are responsible for the rapid depolarization phase of the cardiac contractile cell action potentials. Inhibition of I-Na results in delayed excitability of the cell. Disopyramide also prolongs action potential duration likely through potassium channel blocking. Disopyramide is administered as a racemic mixture. In vitro studies have demonstrated that the S-(+) isomer has pharmacological action similar to quinidine. The R-(-) isomer blocks sodium channels, but does not prolong action potential duration. Disopyramide may be used to maintain rhythm in atrial fibrillation or flutter or to prevent recurrence of ventricular tachycardia or fibrillation. Disopyramide may depress cardiac contractility, which could precipitate heart failure or Torsades de Pointes. "
What is the definition of Fosphenytoin (Antiarrhythmic) Action Pathway?,"This pathway illustrates the fosphenytoin targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cells’ extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Fosphenytoin, an antiepileptic drug that exhibits Class 1B antiarrhythmic effects, is a soluble pro-drug phosphate ester. It is rapidly absorbed intramuscularly and rapidly metabolized in the blood stream by plasma esterases to the active drug, phenytoin. Fosphenytoin was developed to replace parenteral phenytoin sodium for the treatment of epileptic seizures. Parenteral phenytoin sodium was originally prepared in 40% propylene glycol and 10% ethanol at pH 12. This formulation exhibited a range of toxic effects from severe irritation and pain at the injection site to occasional death from rapid injections. Although fosphenytoin is used to treat epileptic seizures, antiarrhythmic effects have also been observed. The active metabolite, phenytoin, preferentially binds to sodium channels (I-Na) in their inactive state. This causes a slight delay in the rapid depolarization phase of cardiac myocyte action potentials. In contrast to Class 1A antiarrhythmic drugs (e.g. quinidine) which prolong action potential duration, fosphenytoin and other Class 1B antiarrhythmics reduce the refractory period or action potential duration due to their membrane stabilizing effects. Phenytoin has been found to be beneficial in the treatment of atrial and ventricular arrhythmias. "
What is the definition of Phenytoin (Antiarrhythmic) Action Pathway?,"This pathway illustrates the phenytoin targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cells’ extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Phenytoin is an antiepileptic drug that exhibits Class 1B antiarrhythmic activity. Although phenytoin is used to treat epileptic seizures, beneficial antiarrhythmic effects have also been observed. Phenytoin preferentially binds to sodium channels (I-Na) in their inactive state. This causes a slight delay in the rapid depolarization phase of cardiac myocyte action potentials. In contrast to Class 1A antiarrhythmic drugs (e.g. quinidine) which prolong action potential duration, phenytoin and other Class 1B antiarrhythmics reduce the refractory period or action potential duration due to their membrane stabilizing effects. Phenytoin has been found to be beneficial in the treatment of atrial and ventricular arrhythmias. "
What is the definition of Lidocaine (Antiarrhythmic) Action Pathway?,"This pathway illustrates the lidocaine targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cells’ extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Lidocaine is a local anaesthetic that is also used to treat ventricular arrhythmias in emergency situations. It is a Class 1B antiarrhythmic drug that binds to sodium channels in their open and closed inactive state. Voltage-gated sodium channels are responsible for the inward sodium current (I-Na) that causes the rapid depolarization phase of cardiac myocyte action potentials. Inhibition of the sodium current increases the threshold of excitability of cells and decreases automaticity. Like other Class 1B antiarrythmics, lidocaine causes a slight decrease in action potential duration due to its membrane stabilizing effects. Lidocaine is not effective for treating atrial arrhythmias. Lidocaine undergoes rapid hepatic metabolism (t1/2 = 15 – 30 minutes) by cytochrome P450 enzymes, CYP2C6 and CYP3A4. As a result, other related drugs with longer half-lives, such as mexiletine and tocainide, were developed. "
What is the definition of Mexiletine Action Pathway?,"This pathway illustrates the mexiletine targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cells’ extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Mexiletine is a Class 1B antiarrhythmic drug with electrophysiological effects similar to lidocaine and tocainide. Mexiletine preferentially binds to voltage-gated sodium channels in their inactive state inhibiting the sodium current (I-Na) responsible for the rapid depolarization phase of the cardiac myocyte action potential. Inhibition of I-Na increases the cells’ threshold of excitability. The membrane-stabilizing effects of mexiletine causes a slight decrease in the action potential duraction. Mexiletine was developed as an alternative to lidocaine, which is subject to rapid hepatic metabolism and has a short half-life of only 15 – 30 minutes. Mexiletine is subject to less first pass metabolism compared to lidocaine and can be administered as chronic oral therapy. Mexiletine may be used to treat ventricular arrhythmias. "
What is the definition of Tocainide Action Pathway?,"This pathway illustrates the tocainide targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cellsŠ—È extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Tocainide, the alpha-methyl analogue of lidocaine, is a Class 1B antiarrhythmic drug. It has similar electrophysiological effects as lidocaine and may be used to treat ventricular arrhythmias. Unlike lidocaine, tocainide may be administered orally and has a long plasma half-life of 12 hours (plasma t1/2 of lidocaine = 15 Š—– 30 minutes). Like other Class 1B antiarrhythmic agents, tocainide preferentially blocks sodium channels in their inactivated state. Voltage-gated sodium channels (I-Na) are responsible for the rapid depolarization phase of cardiac myocyte action potentials. Inhibition of I-Na results in an increased threshold of excitability and decreased automaticity. The membrane stabilizing effects of tocainide also cause a slight decrease in action potential duration. Tocainide is administered as a racemic mixture. The R-isomer is four times more potent than the S-isomer and is cleared faster in anephric patients. "
What is the definition of Flecainide Action Pathway?,"This pathway illustrates the flecainide targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cellsŠ—È extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Flecainide is a Class 1C antiarrhythmic drug. Like other Class 1 antiarrhythmic agents (e.g. quinidine), flecainide blocks sodium ion currents (I-Na) through voltage-gated sodium channels with preferential binding to channels in their open activated state. The therapeutic effects of flecainide are thought to arise from their slow dissociation from sodium channels, which alters the pattern of action potential propagation. Flecainide also blocks potassium currents via the voltage-gated rapid delayed rectifying potassium channel (I-Kr) and blocks the extrusion of calcium ions from the sarcoplasmic reticulum (SR) to the cytosol via the cardiac ryanodine receptor (RYR2) of the SR membrane. Flecainide shortens the action potential duration in Purkinje cells, but prolongs it in ventricular cells. Due to its proarrhythmic effects, flecainide increased mortality in patients recovering from myocardial infarctions in the CAST study. However, in the absence of heart disease, it is still used to maintain sinus rhythm in patients with supraventricular arrhythmias, such as atrial fibrillation, ventricular tachycardia and supraventricular tachycardia. "
What is the definition of Ibutilide Action Pathway?,"This pathway illustrates the ibutilide targets involved in antiarrhythmic therapy. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside the cell is negatively charged relative to the cellsŠ—È extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Ibutilide is a Class III antiarrhythmic drug that blocks potassium current through the voltage-gated rapid delayed rectifying potassium channel (I-Kr). I-Kr is partially responsible for the final repolarization phase of the cardiac myocyte action potential. As such, I-Kr antagonism delays repolarization and increases action potential duration. Ibutilide also activates a slow inward sodium current (not shown) which likely contributes to action potential prolongation. Ibutilide may be used to treat atrial fibrillation or atrial flutter. It may cause Torsades de Pointes in up to 6% of patients. "
What is the definition of Diltiazem Action Pathway?,"Diltiazem is a benzothiazepine calcium channel blocker (CCB) or antagonist, the only drug of this class in clinical use. There are at least five different types of calcium channels in Homo sapiens: L-, N-, P/Q-, R- and T-type. CCBs target L-type calcium channels, the major channel in muscle cells that mediates contraction. Diltiazem is thought to primarily block L-type calcium channels in their open state. It is one of only two clinically used CCBs that are cardioselective. Diltiazem and verapamil, the other cardioselective CCB, shows greater activity against cardiac calcium channels than those of the peripheral vasculature. Other CCBs, such as nifedipine and amlodipine, have little to no effect on cardiac cells (cardiac myocytes and cells of the SA and AV nodes). Due to its cardioselective properties, diltiazem may be used to treat arrhythmias (e.g. atrial fibrillation, atrial flutter and paroxysmal supraventrucular tachycardia) as well as hypertension. The first part of this pathway depicts the pharmacological action of diltiazem on cardiac myocytes and peripheral arterioles and coronary arteries. Diltiazem decreases cardiac myocyte contractility by inhibiting the influx of calcium ions. Calcium ions entering the cell through L-type calcium channels bind to calmodulin. Calcium-bound calmodulin then binds to and activates myosin light chain kinase (MLCK). Activated MLCK catalyzes the phosphorylation of the regulatory light chain subunit of myosin, a key step in muscle contraction. Signal amplification is achieved by calcium-induced calcium release from the sarcoplasmic reticulum through ryanodine receptors. Inhibition of the initial influx of calcium decreases the contractile activity of cardiac myocytes and results in an overall decreased force of contraction by the heart. Diltiazem affects smooth muscle contraction and subsequent vasoconstriction in peripheral arterioles and coronary arteries by the same mechanism. Decreased cardiac contractility and vasodilation lower blood pressure. The second part of this pathway illustrates the effect of calcium channel antagonism on the cardiac action potentials. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside of the cell is negatively charged relative to the cellsŠ—È extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Blocking L-type calcium channels decreases conduction and increases the refractory period. DiltiazemŠ—Ès effects on pacemaker cells enable its use as a rate-controlling agent in atrial fibrillation. "
What is the definition of Nebivolol Action Pathway?,"Nebivolol (also known as Bystolic or Nebivololum) is a β1-receptor blocker (selective β1-receptor antagonist) that can bind and inhibit Beta-1 adrenergic receptor in muscule and heart. Nebivolol competes with epinephrine or other beta-1 adrenergic receptor activator to bind on the receptor, which can reduce the heart rate and blood pressure that could caused by biniding of epinephrine on receptor. Nebivolol can also prevent release of renin (a hormone from kidneys), which can result in reduced level of constriction of blood vessels."
What is the definition of Carvedilol Action Pathway?,"Carvedilol, trade name Coreg, is a nonselective beta-blocker that blocks both alpha and beta receptors of the heart and blood vessels. It is prescribed to treat hypertension, stable angina pectoris and congestive heart failure. Carvedilol also blocks calcium channels. Its activity decreases heart rate, myocardial contractility and oxygen demand and decreases vascular resistance. It also posses a unique feature for a beta-blocker, it has an anti-free-radical effect. This effect may prevent free radical damage to treat chronic heart failure."
What is the definition of Labetalol Action Pathway?,"Labetalol (also known as Albetol or Ibidomide) is an inhibitor/antagonist of beta-1 adrenergic receptor that can be used for treating high blood pressure and reducing cardiac output. Labetalol can bind to beta-1 adrenergic receptor on both vascular smooth muscle, which lead to inhibition of vasoconstriction in peripheral blood vessels and adrenergic stimulation of endothelial cell function. "
What is the definition of Verapamil Action Pathway?,"Verapamil is a phenylalkylamine calcium channel blocker (CCB) or antagonist. There are at least five different types of calcium channels in Homo sapiens: L-, N-, P/Q-, R- and T-type. CCBs target L-type calcium channels, the major channel in muscle cells that mediates contraction. Verapamil, an organic cation, is thought to primarily block L-type calcium channels in their open state by interfering with the binding of calcium ions to the extracellular opening of the channel. It is one of only two clinically used CCBs that are cardioselective. Verapamil and diltiazem and, the other cardioselective CCB, shows greater activity against cardiac calcium channels than those of the peripheral vasculature. Other CCBs, such as nifedipine and amlodipine, have little to no effect on cardiac cells (cardiac myocytes and cells of the SA and AV nodes). Due to its cardioselective properties, verapamil may be used to treat arrhythmias (e.g. atrial fibrillation) as well as hypertension. The first part of this pathway depicts the pharmacological action of verapamil on cardiac myocytes and peripheral arterioles and coronary arteries. Verapamil decreases cardiac myocyte contractility by inhibiting the influx of calcium ions. Calcium ions entering the cell through L-type calcium channels bind to calmodulin. Calcium-bound calmodulin then binds to and activates myosin light chain kinase (MLCK). Activated MLCK catalyzes the phosphorylation of the regulatory light chain subunit of myosin, a key step in muscle contraction. Signal amplification is achieved by calcium-induced calcium release from the sarcoplasmic reticulum through ryanodine receptors. Inhibition of the initial influx of calcium decreases the contractile activity of cardiac myocytes and results in an overall decreased force of contraction by the heart. Verapamil affects smooth muscle contraction and subsequent vasoconstriction in peripheral arterioles and coronary arteries by the same mechanism.  Decreased cardiac contractility and vasodilation lower blood pressure. The second part of this pathway illustrates the effect of calcium channel antagonism on the cardiac action potentials. Contractile activity of cardiac myocytes is elicited via action potentials mediated by a number of ion channel proteins. During rest, or diastole, cells maintain a negative membrane potential; i.e. the inside of the cell is negatively charged relative to the cellsŠ—È extracellular environment. Membrane ion pumps, such as the sodium-potassium ATPase and sodium-calcium exchanger (NCX), maintain low intracellular sodium (5 mM) and calcium (100 nM) concentrations and high intracellular potassium (140 mM) concentrations. Conversely, extracellular concentrations of sodium (140 mM) and calcium (1.8 mM) are relatively high and extracellular potassium concentrations are low (5 mM). At rest, the cardiac cell membrane is impermeable to sodium and calcium ions, but is permeable to potassium ions via inward rectifier potassium channels (I-K1), which allow an outward flow of potassium ions down their concentration gradient. The positive outflow of potassium ions aids in maintaining the negative intracellular electric potential. When cells reach a critical threshold potential, voltage-gated sodium channels (I-Na) open and the rapid influx of positive sodium ions into the cell occurs as the ions travel down their electrochemical gradient. This is known as the rapid depolarization or upstroke phase of the cardiac action potential. Sodium channels then close and rapidly activated potassium channels such as the voltage-gated transient outward delayed rectifying potassium channel (I-Kto) and the voltage-gated ultra rapid delayed rectifying potassium channel (I-Kur) open. These events make up the early repolarization phase during which potassium ions flow out of the cell and sodium ions are continually pumped out. During the next phase, known as the plateau phase, calcium L-type channels (I-CaL) open and the resulting influx of calcium ions roughly balances the outward flow of potassium channels. During the final repolarization phase, the voltage-gated rapid (I-Kr) and slow (I-Ks) delayed rectifying potassium channels open increasing the outflow of potassium ions and repolarizing the cell. The extra sodium and calcium ions that entered the cell during the action potential are extruded via sodium-potassium ATPases and NCX and intra- and extracellular ion concentrations are restored. In specialized pacemaker cells, gradual depolarization to threshold occurs via funny channels (I-f). Blocking L-type calcium channels decreases conduction and increases the refractory period. VerapamilŠ—Ès effects on pacemaker cells enable its use as a rate-controlling agent in atrial fibrillation. "
What is the definition of Amlodipine Action Pathway?,"Amlodipine, trade name Norvasc, is a dihydropyridine calcium channel blocker (CCB) prescribed to treat hypertension and exertion-related angina. The drug acts directly on vascular smooth muscle to cause peripheral vasodilation. Amlodipine inhibits the influx of calcium ions into vascular smooth muscle and cardiac muscle to bind calmodulin. Inhibition of calcium bound calmodulin prevents activation of myosin light chain kinase and phosphorylation of the regulatory light chain subunit of myosin, this inhibits an integral part of muscle contractions. The net effect is decreased contractility of arterial smooth muscle and increased vasodilation resulting in a decrease in blood pressure. Amlodipine has arterial selectivity due to alternative splicing of the channel and has little effect on cardiac muscle. "
What is the definition of Felodipine Action Pathway?,"Felodipine belongs to the dihydropyridine (DHP) class of calcium channel blockers (CCBs), the most widely used class of CCBs.  CCBs target L-type calcium channels, the major channel in muscle cells that mediates contraction.  Similar to other DHP CCBs, felodipine binds directly to inactive calcium channels stabilizing their inactive conformation.  Since arterial smooth muscle depolarizations are longer in duration than cardiac muscle depolarizations, inactive channels are more prevalent in smooth muscle cells.  Alternative splicing of the alpha-1 subunit of the channel gives felodipine additional arterial selectivity.  At therapeutic sub-toxic concentrations, felodipine has little effect on cardiac myocytes and conduction cells.  This pathway depicts the pharmacological action of felodipine on arterial smooth muscle cells.  Felodipine decreases arterial smooth muscle contractility and subsequent vasoconstriction by inhibiting the influx of calcium ions through L-type calcium channels.  Calcium ions entering the cell through these channels bind to calmodulin.  Calcium-bound calmodulin then binds to and activates myosin light chain kinase (MLCK).  Activated MLCK catalyzes the phosphorylation of the regulatory light chain subunit of myosin, a key step in muscle contraction.  Signal amplification is achieved by calcium-induced calcium release from the sarcoplasmic reticulum through ryanodine receptors.  Inhibition of the initial influx of calcium decreases the contractile activity of arterial smooth muscle cells and results in vasodilation.  The vasodilatory effects of felodipine result in an overall decrease in blood pressure.  Felodipine may be used to treat mild to moderate essential hypertension.  . "
What is the definition of Isradipine Action Pathway?,"Isradipine (also known as DynaCirc or Prescal) is a calcium channel blocker within dihydropyridine (DHP) class that can be used for treating high blood pressure and essential hypertension. There are at least 5 different types of calcium channels in human which are L-, N-, P/Q-, R- and T-type. Isradipine only targets the L-type that mediate muscle cell contraction by binding for stabilizing their inactive conformation. Inactivated calcium channel are more frequent in smooth muscle cells because of longer depolarizations. This pathway demonstrates the binding of isradipine on arterial smooth muscle cells inhibits the influx of calcium ions, which lead to decreased arterial smooth muscle contractility and subsequent vasoconstriction. Calcium ion enters the cell and bind to calmodulin,  and then calcium-bound calmodulin binds and activates myosin light chain kinase (MLCK). Activated myosin light chain kinase (MLCK) can phosphorylate subunit of myosin, which is an important step for muscle contraction. Therefore, binding and inhibiting of calcium channels can lead to inhibition of influx of calcium that result in decreased contractile activity (vasodilation). Vasodilatory effects can reduced the blood pressure. "
What is the definition of Nifedipine Action Pathway?,"Nifedipine (also known as Adalat or Procardia) is a dihydropyridine calcium channel blocker that may be used for treatment of hypertension and exertion-related angina in the absence of vasospasm. Nifedipine binds the major channel in muscle cells: L-type calcium channels. Binding of Nifedipine on L-type calcium channels can change channels' confirmation to its inactive form, so that the channel couldn't faciltate the influx of calcium ions, which leads to decreased arterial smooth muscle contractility and subsequent vasoconstriction. Activated mysoin light chain kinase (MLCK) is required for muscle contraction since it can catalyze the phosphorylation of the regulatory light chain subunit of myosin. Without calcium ions in muscle cell, calmodulin couldn't form the calcium-bound calmodulin, which is required for binding and activating MLCK. Lack of initial influx of calcium can also reduce the level of contractile activity of muscle cells and results in vasodilation, which ultimately lead to overall decresing in blood pressure. "
What is the definition of Nimodipine Action Pathway?,"Nimodipine (also known as Nimotop or Periplum) is a dihydropyridine calcium channel blocker that may not be used for treatment of hypertension. Compared to other DHP CCBs, nimodipine is more active in the cerebral vasculature than in the periphery. This may be due to its high lipophilicity and ability to penetrate the blood brain barrier. This unique property of nimodipine led to clinical studies for its use to improve neurological outcomes in patients following subarachnoid hemorrhage from ruptured intracranial aneurysms. While it has been approved as adjunct treatment for this indication, the exact mechanism by which it exerts these effects is unclear. Nimodipine has little effect on cardiac myocytes and conduction cells at therapeutic sub-toxic concentrations. Nimodipine binds the major channel in muscle cells: L-type calcium channels. Binding of Nimodipine on L-type calcium channels can change channels' confirmation to its inactive form, so that the channel couldn't faciltate the influx of calcium ions, which leads to decreased arterial smooth muscle contractility and subsequent vasoconstriction. Activated mysoin light chain kinase (MLCK) is required for muscle contraction since it can catalyze the phosphorylation of the regulatory light chain subunit of myosin. Without calcium ions in muscle cell, calmodulin couldn't form the calcium-bound calmodulin, which is required for binding and activating MLCK. Lack of initial influx of calcium can also reduce the level of contractile activity of muscle cells and results in vasodilation, which ultimately lead to overall decresing in blood pressure."
What is the definition of Nisoldipine Action Pathway?,"Nisoldipine (also known as Sular or Nisocor) is a dihydropyridine calcium channel blocker that may be used for treatment of hypertension, chronic stable angina and Prinzmetal's variant angina. Nisoldipine binds the major channel in muscle cells: L-type calcium channels. Binding of Nisoldipine on L-type calcium channels can change channels' confirmation to its inactive form, so that the channel couldn't faciltate the influx of calcium ions, which leads to decreased arterial smooth muscle contractility and subsequent vasoconstriction. Activated mysoin light chain kinase (MLCK) is required for muscle contraction since it can catalyze the phosphorylation of the regulatory light chain subunit of myosin. Without calcium ions in muscle cell, calmodulin couldn't form the calcium-bound calmodulin, which is required for binding and activating MLCK. Lack of initial influx of calcium can also reduce the level of contractile activity of muscle cells and results in vasodilation, which ultimately lead to overall decresing in blood pressure."
What is the definition of Nitrendipine Action Pathway?,"Nitrendipine (also known as Bayotensin or Nidrel) is a dihydropyridine calcium channel blocker that may be used for treatment of hypertension. Nitrendipine binds the major channel in muscle cells: L-type calcium channels. Binding of nitrendipine on L-type calcium channels can change channels' confirmation to its inactive form, so that the channel couldn't faciltate the influx of calcium ions, which leads to decreased arterial smooth muscle contractility and subsequent vasoconstriction. Activated mysoin light chain kinase (MLCK) is required for muscle contraction since it can catalyze the phosphorylation of the regulatory light chain subunit of myosin. Without calcium ions in muscle cell, calmodulin couldn't form the calcium-bound calmodulin, which is required for binding and activating MLCK. Lack of initial influx of calcium can also reduce the level of contractile activity of muscle cells and results in vasodilation, which ultimately lead to overall decresing in blood pressure. "
What is the definition of Benzocaine Action Pathway?,"Benzocaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Benzocaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore benzocaine preferentially inhibits neurons that are actively firing."
What is the definition of Bupivacaine Action Pathway?,"Bupivacaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Bupivacaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore bupivacaine preferentially inhibits neurons that are actively firing. "
What is the definition of Chloroprocaine Action Pathway?,"Chloroprocaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Chloroprocaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore chloroprocaine preferentially inhibits neurons that are actively firing. "
What is the definition of Cocaine Action Pathway?,"Cocaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Cocaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore cocaine preferentially inhibits neurons that are actively firing. "
What is the definition of Dibucaine Action Pathway?,"Dibucaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Dibucaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore dibucaine preferentially inhibits neurons that are actively firing. "
What is the definition of Levobupivacaine Action Pathway?,"Levobupivacaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Levobupivacaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore levobupivacaine preferentially inhibits neurons that are actively firing. "
What is the definition of Lidocaine (Local Anaesthetic) Action Pathway?,"Lidocaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Lidocaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore lidocaine preferentially inhibits neurons that are actively firing. "
What is the definition of Mepivacaine Action Pathway?,"Mepivacaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Mepivacaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore mepivacaine preferentially inhibits neurons that are actively firing. "
What is the definition of Oxybuprocaine Action Pathway?,"Oxybuprocaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Oxybuprocaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore oxybuprocaine preferentially inhibits neurons that are actively firing. "
What is the definition of Prilocaine Action Pathway?,"Prilocaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Prilocaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore prilocaine preferentially inhibits neurons that are actively firing. "
What is the definition of Procaine Action Pathway?,"Procaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Procaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore procaine preferentially inhibits neurons that are actively firing. "
What is the definition of Proparacaine Action Pathway?,"Proparacaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Proparacaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore proparacaine preferentially inhibits neurons that are actively firing. "
What is the definition of Ropivacaine Action Pathway?,"Ropivacaine exerts its local anaesthetic effect by blocking voltage-gated sodium channels in peripheral neurons. Ropivacaine diffuses across the neuronal plasma membrane in its uncharged base form. Once inside the cytoplasm, it is protonated and this protonated form enters and blocks the pore of the voltage-gated sodium channel from the cytoplasmic side. For this to happen, the sodium channel must first become active so that so that gating mechanism is in the open state. Therefore ropivacaine preferentially inhibits neurons that are actively firing. "
What is the definition of Codeine Action Pathway?,"Opiate receptors are coupled with G-protein receptors and function as both positive and negative regulators of synaptic transmission via G-proteins that activate effector proteins. Binding of the opiate stimulates the exchange of GTP for GDP on the G-protein complex. As the effector system is adenylate cyclase and cAMP located at the inner surface of the plasma membrane, opioids decrease intracellular cAMP by inhibiting adenylate cyclase. Subsequently, the release of nociceptive neurotransmitters such as substance P, GABA, dopamine, acetylcholine and noradrenaline is inhibited. Opioids also inhibit the release of vasopressin, somatostatin, insulin and glucagon. Codeine's analgesic activity is, most likely, due to its conversion to morphine. Opioids close N-type voltage-operated calcium channels (OP2-receptor agonist) and open calcium-dependent inwardly rectifying potassium channels (OP3 and OP1 receptor agonist). This results in hyperpolarization and reduced neuronal excitability."
What is the definition of Morphine Action Pathway?,"Morphine exerts its analgesic by acting on the mu-opioid receptor of sensory neurons. Binding to the mu-opioid receptor activates associated G(i) proteins. These subsequently act to inhibit adenylate cyclase, reducing the level of intracellular cAMP. G(i) also activates potassium channels and inactivates calcium channels causing the neuron to hyperpolarize. The end result is decreased nerve conduction and reduced neurotransmitter release, which blocks the perception of pain signals."
What is the definition of Heroin Action Pathway?,"Heroin is a mu-opioid agonist. It acts on endogenous mu-opioid receptors that are spread in discrete packets throughout the brain, spinal cord and gut in almost all mammals. Heroin, along with other opioids, are agonists to four endogenous neurotransmitters. They are beta-endorphin, dynorphin, leu-enkephalin, and met-enkephalin. The body responds to heroin in the brain by reducing (and sometimes stopping) production of the endogenous opioids when heroin is present. Endorphins are regularly released in the brain and nerves, attenuating pain."
What is the definition of Methadone Action Pathway?,"Methadone exerts its analgesic by acting on the mu-opioid receptor of sensory neurons. Binding to the mu-opioid receptor activates associated G(i) proteins. These subsequently act to inhibit adenylate cyclase, reducing the level of intracellular cAMP. G(i) also activates potassium channels and inactivates calcium channels causing the neuron to hyperpolarize. The end result is decreased nerve conduction and reduced neurotransmitter release, which blocks the perception of pain signals. Methadone further acts as an antagonist at the NMDA receptor, reducting calcium influx and neuronal excitability."
What is the definition of Oxycodone Action Pathway?,"Oxycodone (also known as OxyContin or Dihydrohydroxycodeinone) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of oxycodone will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Hydromorphone Action Pathway?,"Hydromorphone (also known as dihydromorphinone or Dilaudid) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of hydromorphone will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Hydrocodone Action Pathway?,"Hydrocodone (also known as Vicodin or Norco) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of hydrocodone will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Oxymorphone Action Pathway?,"Oxymorphone (also known as Numorphan) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of oxymorphone will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein."
What is the definition of Alfentanil Action Pathway?,"Alfentanil (also known as Alfenta or Rapifen) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of alfentanil will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Carfentanil Action Pathway?,"Carfentanil (also known as carfentanyl or Wildnil) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of carfentanil will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein."
What is the definition of Fentanyl Action Pathway?,"Carfentanil (also known as Phentanyl or Fentora) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of carfentanil will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Remifentanil Action Pathway?,"Remifentanil is a pharmacologically-active, synthetic, small molecule derived from fentanyl and belongs to a class of drugs called opioids. Opioids are therapeutically employed to achieve analgesia. Remifentanial’s rapid mechanism of action primarily involves its agonistic effects on mu-type opioid receptors which are inhibitory G-coupled protein receptors and lead to the inhibition of adenylate cyclase and decrease in cAMP production. Analgesia, anesthesia, and respiratory depression are a function of remifentanial’s action on these mu-type opioid receptors."
What is the definition of Sufentanil Action Pathway?,"Sufentanil is a pharmacologically-active synthetic small molecule derived from fentanyl and belongs to a class of drugs called opioids. Opioids are therapeutically employed to achieve analgesia. Sufentanil’s rapid mechanism of action primarily involves its agonistic effects on mu-type opioid receptors which are inhibitory G-coupled protein receptors and lead to the inhibition of adenylate cyclase and decrease in cAMP production. It also inhibits nociceptive neurotransmitter release and induces membrane hyperpolarization. Analgesia, anesthesia, and respiratory depression are a consequence of remifentanial’s action."
What is the definition of Imipramine Action Pathway?,"Imipramine is a tricyclic antidepressant that exerts its therapeutic effects by inhibiting norepinephrine and serotonin reuptake in the brain. It does so by competing for the same binding site as norepinephrine on the sodium-dependent noradraneline transporter (SLC6A2) and by competing with serotonin for binding to the sodium-dependent serotonin transporter (SLC6A4). This increases the concentrations of both norepinephrine and serotonin in their respective synapses and reverses the state of low concentrations of both neurotransmitters found in depression. Higher concentrations of norepinephrine and serotonin have also been shown to have long-term neuromodulatory effects. Binding of these neurotransmitters to their respective receptors activate adenylate cyclase, which produces cAMP. cAMP activates protein kinase A which activates cAMP-responsive binding protein 1 (CREB-1). CREB-1 enters the nucleus and affects transcription of brain-derived neurotrophic factor (BDNF). BDNF subsequently stimulates neurogenesis, which may contribute to the long-term reversal of depression.  Imipramine is metabolized in the liver mostly through N-demethylation by CYP2C19 into desipramine. Desipramine is an active metabolite and also has similar actions to imipramine on norepinephrine and serotonin reuptake."
What is the definition of Desipramine Action Pathway?,"Desipramine is a tricyclic antidepressant that exerts its therapeutic effects by inhibiting norepinephrine and serotonin reuptake in the brain. It does so by competing for the same binding site as norepinephrine on the sodium-dependent noradraneline transporter (SLC6A2) and by competing with serotonin for binding to the sodium-dependent serotonin transporter (SLC6A4). This increases the concentrations of both norepinephrine and serotonin in their respective synapses and reverses the state of low concentrations of both neurotransmitters found in depression. Higher concentrations of norepinephrine and serotonin have also been shown to have long-term neuromodulatory effects. Binding of these neurotransmitters to their respective receptors activate adenylate cyclase, which produces cAMP. cAMP activates protein kinase A which activates cAMP-responsive binding protein 1 (CREB-1). CREB-1 enters the nucleus and affects transcription of brain-derived neurotrophic factor (BDNF). BDNF subsequently stimulates neurogenesis, which may contribute to the long-term reversal of depression. "
What is the definition of Citalopram Action Pathway?,"Citalopram is a selective serotonin reuptake inhibitor that exerts antidepressive effects by selectively inhibiting serotonin reuptake in the brain. It does so by competing for the same binding site as serotonin on the the sodium-dependent serotonin transporter (SLC6A4). This increases the concentrations of serotonin in the synaptic cleft and reverses the state of low concentration seen in depression. Higher concentration of serotonin has also been shown to have long-term neuromodulatory effects. Binding of serotonin to certain serotonin receptors activate adenylate cyclase, which produces cAMP. cAMP activates protein kinase A which activates cAMP-responsive binding protein 1 (CREB-1). CREB-1 enters the nucleus and affects transcription of brain-derived neurotrophic factor (BDNF). BDNF subsequently stimulates neurogenesis, which may contribute to the long-term reversal of depression. "
What is the definition of Escitalopram Action Pathway?,"Escitalopram is a selective serotonin reuptake inhibitor that exerts antidepressive effects by selectively inhibiting serotonin reuptake in the brain. It does so by competing for the same binding site as serotonin on the the sodium-dependent serotonin transporter (SLC6A4). This increases the concentrations of serotonin in the synaptic cleft and reverses the state of low concentration seen in depression. Higher concentration of serotonin has also been shown to have long-term neuromodulatory effects. Binding of serotonin to certain serotonin receptors activate adenylate cyclase, which produces cAMP. cAMP activates protein kinase A which activates cAMP-responsive binding protein 1 (CREB-1). CREB-1 enters the nucleus and affects transcription of brain-derived neurotrophic factor (BDNF). BDNF subsequently stimulates neurogenesis, which may contribute to the long-term reversal of depression. "
What is the definition of Fluoxetine Action Pathway?,"Fluoxetine is a selective serotonin reuptake inhibitor that exerts antidepressive effects by selectively inhibiting serotonin reuptake in the brain. It does so by competing for the same binding site as serotonin on the the sodium-dependent serotonin transporter (SLC6A4). This increases the concentrations of serotonin in the synaptic cleft and reverses the state of low concentration seen in depression. Higher concentration of serotonin has also been shown to have long-term neuromodulatory effects. Binding of serotonin to certain serotonin receptors activate adenylate cyclase, which produces cAMP. cAMP activates protein kinase A which activates cAMP-responsive binding protein 1 (CREB-1). CREB-1 enters the nucleus and affects transcription of brain-derived neurotrophic factor (BDNF). BDNF subsequently stimulates neurogenesis, which may contribute to the long-term reversal of depression. "
What is the definition of Thioguanine Action Pathway?,"Thioguanine is a purine antimetabolite prodrug closely related to mercaptopurine and similarly inhibits purine metabolism. The thioguanine pathway is shown as a part of the mercaptopurine pathway. Thioguanine exerts cytotoxic effects via incorporation of thiodeoxyguanosine triphosphate into DNA and thioguanosine triphosphate into RNA and inhibition of Ras-related C3 botulinum toxin substrate 1, which induces apoptosis of activated T cells. Once in a cell, thioguanine is converted to thioguanosine monophosphate by hypoxanthine-guanine phosphoribosyltransferase. Thioguanosine monophosphate is then phosphorylated to thioguanosine diphosphate, which is converted via a thiodeoxyguanosine diphosphate intermediate to thiodeoxyguanosine triphosphate. Thiodeoxyguanosine triphosphate is incorporated into DNA causing cytotoxicity. Thioguanosine diphosphate is also converted to thioguanosine triphosphate which is incorporated into RNA. The thioguanosine triphosphate metabolite also inhibits Ras-related C3 botulinum toxin substrate 1, a plasma membrane-associated small GTPase that regulates cellular processes, inducing apoptosis in activated T cells. "
What is the definition of Nicotine Action Pathway?,"Nicotine is a stimulant drug that acts as an agonist at nicotinic acetylcholine receptors. These are ionotropic receptors composed of five homomeric or heteromeric subunits. In the brain, nicotine binds to nicotinic acetylcholine receptors on dopaminergic neurons in the cortico-limbic pathways. This causes the channel to open and allow conductance of multiple cations including sodium, calcium, and potassium. This leads to depolarization, which activates voltage-gated calcium channels and allows more calcium to enter the axon terminal. Calcium stimulates vesicle trafficking towards the plasma membrane and the release of dopamine into the synapse. Dopamine binding to its receptors is responsible the euphoric and addictive properties of nicotine.Nicotine also binds to nicotinic acetylcholine receptors on the chromaffin cells in the adrenal medulla. Binding opens the ion channel allowing influx of sodium, causing depolarization of the cell, which activates voltage-gated calcium channels. Calcium triggers the release of epinephrine from intracellular vesicles into the bloodstream, which causes vasoconstriction, increased blood pressure, increased heart rate, and increased blood sugar."
What is the definition of Disulfiram Action Pathway?,"Disulfiram is a drug used in the treatment of cocaine addiction and chronic alcoholism. With regards to cocaine addiction, cocaine inhibits dopamine reuptake by blocking dopamine transporter 1 (DAT1). This increases dopamine concentrations in the synapse and dopamine binding to its receptors induces euphoria. Disulfiram inhibits dopamine beta-hydroxylase, which metabolizes dopamine into norepinephrine.  This causes more dopamine to accumulate in the axon terminal and more dopamine is released. When used concomitantly with cocaine, this causes an extremely high concentration of dopamine in the synapse that does not increase the euphoric effects of cocaine, but rather induces an unpleasant sensation of anxiety. This serves to discourage the patient from using cocaine while taking disulfiram. Disulfiram can prevent alcohol metabolism by inhibiting acetaldehyde dehydrogenase in mitochondria, which lead to increased level of acetaldehyde, and eventually result in hangover (e.g. flushing, vomiting, headache, etc.) as the main symptoms. Therefore, disulfiram is not suggested to take while patient consuming alcohol."
What is the definition of Nateglinide Action Pathway?,"Nateglinide is a non-sulfonylurea insulin secretagogue used in the treatment of type 2 diabetes. As the name of the drug class suggests, nateglinide acts on pancreatic beta-cells to stimulate insulin secretion. Under physiological conditions, insulin secretion from beta-cells is mediated by elevated glucose concentration in the blood. Glucose enters the cell via GLUT2 (SLC2A2) transporters. Once inside the cell, glucose is metabolized to produce ATP. High concentration of ATP will inhibit ATP-dependent potassium channels (ABCC8), which depolarizes the cell. Depolarization causes opening of voltage-gated calcium channels, allowing calcium to enter cell. High intracellular calcium subsequently stimulate vesicle exocytosis and insulin secretion. Nateglinide stimulate insulin secretion in a glucose-sensitive manner by inhibiting ATP-dependent potassium channels. As a result, there tends to be a lesser likelihood of hypoglycemia with nateglinide therapy compared to sulfonylureas."
What is the definition of Repaglinide Action Pathway?,"Repaglinide is a non-sulfonylurea insulin secretagogue used in the treatment of type 2 diabetes. As the name of the drug class suggests, repaglinide acts on pancreatic beta-cells to stimulate insulin secretion. Under physiological conditions, insulin secretion from beta-cells is mediated by elevated glucose concentration in the blood. Glucose enters the cell via GLUT2 (SLC2A2) transporters. Once inside the cell, glucose is metabolized to produce ATP. High concentration of ATP will inhibit ATP-dependent potassium channels (ABCC8), which depolarizes the cell. Depolarization causes opening of voltage-gated calcium channels, allowing calcium to enter cell. High intracellular calcium subsequently stimulate vesicle exocytosis and insulin secretion. Repaglinide stimulate insulin secretion in a glucose-sensitive manner by inhibiting ATP-dependent potassium channels. As a result, there tends to be a lesser likelihood of hypoglycemia with repaglinide therapy compared to sulfonylureas."
What is the definition of Glibenclamide Action Pathway?,"Glibenclamide is a sulfonylurea drug used in the treatment of type 2 diabetes. Glibenclamide acts on pancreatic beta-cells to stimulate insulin secretion. Under physiological conditions, insulin secretion from beta-cells is mediated by elevated glucose concentration in the blood. Glucose enters the cell via GLUT2 (SLC2A2) transporters. Once inside the cell, glucose is metabolized to produce ATP. High concentration of ATP will inhibit ATP-dependent potassium channels (ABCC8), which depolarizes the cell. Depolarization causes opening of voltage-gated calcium channels, allowing calcium to enter cell. High intracellular calcium subsequently stimulate vesicle exocytosis and insulin secretion. Glibenclamide stimulates insulin secretion by directly inhibiting ATP-dependent potassium channels."
What is the definition of Gliclazide Action Pathway?,"Gliclazide is a sulfonylurea drug used in the treatment of type 2 diabetes. Gliclazide acts on pancreatic beta-cells to stimulate insulin secretion. Under physiological conditions, insulin secretion from beta-cells is mediated by elevated glucose concentration in the blood. Glucose enters the cell via GLUT2 (SLC2A2) transporters. Once inside the cell, glucose is metabolized to produce ATP. High concentration of ATP will inhibit ATP-dependent potassium channels (ABCC8), which depolarizes the cell. Depolarization causes opening of voltage-gated calcium channels, allowing calcium to enter cell. High intracellular calcium subsequently stimulate vesicle exocytosis and insulin secretion. Gliclazide stimulates insulin secretion by directly inhibiting ATP-dependent potassium channels."
What is the definition of Adefovir Dipivoxil  Action Pathway?,"Adefovir dipivoxil is an ester prodrug of adefovir, a nucleotide analogue used in the treatment of chronic hepatitis B. Adefovir dipivoxil is taken up into the liver cell and is cleaved into adefovir by intracellular esterases. Adefovir is subsequently phosphorylated first by adenylate kinases and then by nucleoside diphosphate kinases into adefovir diphosphate. Adefovir diphosphate is an analogue of deoxyadenosine triphosphate (dATP) and competes with dATP for binding to the viral DNA polymerase and subsequent incorporation into the growing DNA strand. Once incorporated into the DNA, adefovir causes chain termination, thus preventing viral replication."
What is the definition of Tenofovir  Action Pathway?,"Tenofovir is a nucleotide analogue used in the treatment of HIV and chronic hepatitis B. It is taken up into the cell and is subsequently phosphorylated first by adenylate kinases and then by nucleoside diphosphate kinases into tenofovir diphosphate. Tenofovir diphosphate is an analogue of deoxyadenosine triphosphate (dATP) and competes with dATP for binding to the viral DNA polymerase and subsequent incorporation into the growing DNA strand. Once incorporated into the DNA, tenofovir causes chain termination, thus preventing viral replication."
What is the definition of Prednisone Action Pathway?,"Prednisone is a synthetic glucocorticoid that is used clinically for its anti-inflammatory properties. Prednisone is converted to the active metabolite prednisolone in the liver. Prednisolone can diffuse passively across the cell membrane, where it binds to glucocorticoid receptors in the cytoplasm. Upon binding, the glucocorticoid receptor (GR) dissociates from heat shock protein 90, and translocate into the nucleus. In the nucleus, GR dimers can bind to glucocorticoid response element (GRE) in the promoter region of anti-inflammatory genes, which activates their transcription. GRs also inhibit transcription of inflammatory mediators by binding to negative GRE (nGRE). GRs further interact with the transcription factors cAMP-responsive element binding protein and NF-kappa-B, and inihibit their activation of inflammatory gene transcription. GRs also recruit histone deacetylase 2 to inflammatory genes, which leads to DNA condensation at those loci, thus suppressing expression of those genes."
What is the definition of Prednisolone Action Pathway?,"Prednisolone is a synthetic glucocorticoid that is used clinically for its anti-inflammatory properties. Prednisolone diffuses passively across the cell membrane, where it binds to glucocorticoid receptors in the cytoplasm. Upon binding, the glucocorticoid receptor (GR) dissociates from heat shock protein 90, and translocate into the nucleus. In the nucleus, GR dimers can bind to glucocorticoid response element (GRE) in the promoter region of anti-inflammatory genes, which activates their transcription. GRs also inhibit transcription of inflammatory mediators by binding to negative GRE (nGRE). GRs further interact with the transcription factors cAMP-responsive element binding protein and NF-kappa-B, and inihibit their activation of inflammatory gene transcription. GRs also recruit histone deacetylase 2 to inflammatory gene loci on DNA, which leads to DNA condensation and suppression of gene expression."
What is the definition of Dopamine Activation of Neurological Reward System?,"In the nervous system, dopamine acts as a neurotransmitter with roles in motor control, motivation, arousal, cognition, and reward. The mesolimbic pathway is the main pathway associated with reward, and the dopaminergic neurons of this pathway are found in the substantia nigra (SNc) and  ventral tegmental area (VTA) of the midbrain. Dopamine acts on different G protein-coupled receptor subtyes. The D1-class (D1 and D5) receptors stimulate cAMP production by activating adenylyl cyclase, which activates the reward pathway. The D2-class (D2, D3, and D4) subtypes act oppositely, inhibiting cAMP production by inhibiting adenylyl cyclase. The differing distributions of the receptor subtypes mean that complex outputs often produce a synergistic effect, despite the receptor subtypes having opposite molecular effects (PMID: 20925949, 21303898)."
What is the definition of Excitatory Neural Signalling Through 5-HTR 4 and Serotonin?,"The 5-HT4 receptor is primarily found in the CNS, GI tract, and PNS. Peripheral receptors have important roles in the function of many organ responses (alimentary tract, urinary bladder, heart, and adrenal gland). Alimentary tract receptors have a role in smooth muscle tone, mucosal electrolyte secretion, and the peristaltic reflex. Urinary bladder receptors control cholinergic/purinergic transmission. Atrial heart receptors produce positive inotropy and tachycardia that can precipitate arrhythmias. This receptor is also thought to have roles in anxiety, appetite, GI motility, learning, memory, mood, and respiration. The 5-HT4 receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response."
What is the definition of Corticotropin Activation of Cortisol Production?,"Corticotropin (ACTH or adrenocorticotropic hormone) is a polypeptide tropic hormone produced and secreted by the anterior pituitary gland. It is produced from the cleavage of pre-pro-opiomelanocortin by various endopeptidases, along with other physiologically active peptide fragments such as β-lipotropin, γ-lipotropin, melanocyte stimulating hormone (MSH), and β-endorphin. It is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological stress. Its principal effects are increased production of androgens and cortisol from the adrenal cortex. The ACTHR receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to androgen and cortisol production."
What is the definition of Excitatory Neural Signalling Through 5-HTR 7 and Serotonin?,"The 5-HT7 receptor is primarily found in the CNS, GI tract, and blood vessels. Serotonin is the primary ligand of the 5-HT7 receptor, which activates G(s) proteins associated with the receptor and leads to the activation of adenylyl cyclase and production of the secondary messenger cyclic adenosine monophosphate (cAMP). cAMP activates protein kinase A, phosphorylating downstream effectors that lead to specific cellular responses which mediate physiological functions such as thermoregulation, circadian rhythm, learning and memory, sleep, and potentially mood. "
What is the definition of Excitatory Neural Signalling Through 5-HTR 6 and Serotonin?,The 5-HT6 receptor is primarily expressed in the brain and is involved in glutamatergic and cholinergic neuronal activity.  The 5-HT6 receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response.
What is the definition of Intracellular Signalling Through Adenosine Receptor A2a and Adenosine?,"A member of the G-coupled protein receptor family, the adenosine A2A receptor regulates blood flow to myocardial tissues through the action of vasodilating the coronary arteries, which can potentially lead to hypotension. The adenosine receptor A2a activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response. This occurs through activation of the MAPK/ERK signaling cascade. The A2A receptor has also been demonstrated to play a role in dopamine and glutamate release in the CNS."
What is the definition of Intracellular Signalling Through Adenosine Receptor A2b and Adenosine?,Adenosine is thought to play a role in the pathophysiology of asthma. Stimulation of A2B can induce production of interleukin-8 mast cells. The adenosine receptor A2b activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates down stream effectors that lead to a specific cellular response. This occurs though activation of the MAPK/ERK signaling cascade.
What is the definition of Vasopressin Regulation of Water Homeostasis?,"The vasopressin V2 receptor is found in the kidneys. It serves a role in maintaining corporal water homeostasis. Malfunction of this receptor can lead to Nephrogenic Diabetes Insipidus.Vasopressin (aka Antidiuretic hormone) activates both follicle-stimulating hormone receptor as well as the V2 receptor G protein complex. From this complex, Guanine nucleotide binding protein G(s) protein reacts with Adenylate Cyclase Type 2, Adeonsine Triphosphate, as well as GTP and magnesium to produce cAMP and Pyrophosphate. cAMP then activates PKA (protein kinase A) which leads to changes in the concentration of water in urine."
What is the definition of Intracellular Signalling Through FSH Receptor and Follicle Stimulating Hormone?,"In the ovary, the FSH receptor is necessary for follicular development and is expressed on the granulosa cells. In the male the FSH receptor has been identified on the Sertoli cells that are critical for spermatogenesis.  The FSH receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response."
What is the definition of Intracellular Signalling Through Histamine H2 Receptor and Histamine?,"Histamine is an organic nitrogenous compound that is involved in local immune responses and it is a neurotransmitter for brain. Histamine can mediate various actions by interacting with histamine receptors (H1, H2, H3 and H4). The H2 receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response."
What is the definition of Intracellular Signalling Through LHCGR Receptor and Luteinizing Hormone/Choriogonadotropin?,"Its activation is necessary for the hormonal functioning during reproduction. LHCGRs are found in the ovary, testis, and many extragonadal tissues.In the ovary, the LHCG receptor is necessary for follicular maturation and ovulation, as well as luteal function. In the male the LHCGR has been identified on the Leydig cells that are critical for testosterone production, and support spermatogenesis. The LHCGRs receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response."
What is the definition of Intracellular Signalling Through PGD2 receptor and Prostaglandin D2?,PGD is the major prostanoid released from human mast cells upon immunological challenge. Prostaglandin D2 (PGD2) can trigger asthmatic responses by acting as a cell-derived mediator in mice. The PGD receptor activates G(s) proteins which lead to the activation of adenylyl cyclase which produces the secondary messenger cAMP. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response.
What is the definition of Intracellular Signalling Through Prostacyclin Receptor and Prostacyclin?,"Cyclooxygenase is the major producer of prostacyclin. Prostacyclin binding to its receptor increases vasodilation and decreases platelet aggregation. The receptor is a G-protein coupled receptor, upon its binding it activates G proteins causing the activation of adenylyl cyclase and production of cAMP messenger molecules. cAMP activates PKA (protein kinase A) which phosphorylates downstream effectors that lead to a specific cellular response.In vasodilation, the PKA activity causes phosphorylation of MLCK, decreasing its activity, resulting in dephosphorylation of MLC of myosin. This leads to smooth muscle relaxation resulting in vasodilation."
What is the definition of Fc Epsilon Receptor I Signaling in Mast Cells?,"Fc epsilon receptor 1 (Fc epsilon RI) is a high-affinity receptor for the Fc region of immunoglobulin E (IgE), an antibody isotope involved in allergies. The antigens of allergens bind to IgE antibodies, which then interact with Fc epsilon RIs on the surface of mast cells. This activates the mast cells and results in degranulation, a process by which preformed granules containing histamine, proteoglycans, and serine proteases, are released. Activated mast cells also synthesize and secrete lipid-derived mediators (such as prostaglandins, leukotrienes, and platelet-activating factor) and cytokines (notably tumor necrosis factor-alpha, interleukin-4, and interleukin-5). The release of these compounds results in the inflammatory response."
What is the definition of Insulin Signalling?,"Insulin is responsible for the regulation of glucose levels in the body. It stimulates the storage of energy and inhibits the breakdown of high energy metabolites. Glycogen and lipid biosynthesis are upregulated, and conversely, glycogen and fatty acid metabolism are down-regulated. Insulin also modulates transcription and translation. Binding of insulin to the insulin receptor (IR) results in the activation of its tyrosine kinase activity leading to IR autophosphorylation. IR then phosphorylates several substrates that lead to the activation of an intracellular signalling cascade. IR activation leads to the activation of H-Ras, MAPK1-3, and PI3-kinase pathways. The activation of these pathways leads to modulation of key proteins in glycogen metabolism/lipid metabolism and transcription/translation."
What is the definition of DNA Replication Fork?,"DNA is composed of two long and complementary strands, with a backbone on the outside and nucleotides in the middle. During replication the two strands of DNA separate; the resulting structure is called the replication fork. The replication fork forms because enzymes called helicases surround the DNA strands and break the hydrogen bonds which hold them together. The result is that two long branches, almost like fork prongs, each of which is a DNA strand. Replication of DNA has two main different processes. Because DNA is replicated in the 5' to 3' direction, and because both DNA strands in the replication fork are negative mirror images of each other, and because the replication fork is created on only one direction down the length of the DNA, two types of replication strands are formed: the leading and the lagging strand. These strands are so named by the way in which DNA polymerase reads the original DNA strand and attaches the complementary nucleotides as it makes its way along the chain. Because the direction of the movement of the replication fork, and the direction of the addition of nucleotides in the leading strand is the same, the process is continuous.That is, a polymerase is able to read the DNA and add the matching nucleotide bases to it continuously. In prokaryotes DNA polymerase III is responsible for creating the leading strand. The lagging strand is oriented in the opposite direction to the leading strand. Thus, replication of the lagging strand occurs in the opposing direction to that of the leading strand and the replication fork. As a result, replication of the lagging strand is a slower and more complicated process than that of the leading strand. Thus it is seen to lag behind the leading strand (hence the name)."
What is the definition of Nucleotide Excision Repair ?,"In order to pass genetic information from one generation to the next, all organisms must accurately replicate their genomes during each cell division. This includes the nuclear genome and mitochondrial and chloroplast genomes. These are normally replicated with high fidelity that is achieved through the action of accurate DNA repair. Nucleotide Excision Repair is one os several mechanisms of DNA repair.  Nucleotide excision repair (NER) operates on base damage caused by exogenous agents (such as mutagenic and carcinogenic chemicals and photoproducts generated by sunlight exposure) that cause alterations in the chemistry and structure of the DNA duplex . Such damage is recognized by a protein called XPC, which is stably bound to another protein called HHRAD23B (R23). The binding of the XPC–HHRAD23 heterodimeric subcomplex is followed by the binding of several other proteins (XPA, RPA, TFIIH and XPG). Of these, XPA and RPA are believed to facilitate specific recognition of base damage. TFIIH is a subcomplex of the RNA polymerase II transcription initiation machinery which also operates during NER. It consists of six subunits and contains two DNA helicase activities (XPB and XPD) that unwind the DNA duplex in the immediate vicinity of the base damage. This local denaturation generates a bubble in the DNA, the ends of which comprise junctions between duplex and single-stranded DNA. The subsequent binding of the ERCC1–XPF heterodimeric subcomplex generates a completely assembled NER multiprotein complex. XPG is a duplex/single-stranded DNA endonuclease that cuts the damaged strand at such junctions 3’ to the site of base damage. Conversely, the ERCC1–XPF heterodimeric protein is a duplex/single-stranded DNA endonuclease that cuts the damaged strand at such junctions 5’ to the site of base damage. This bimodal incision generates an oligonucleotide fragment 27–30 nucleotides in length which includes the damaged base. This fragment is excised from the genome, concomitant with restoring the potential 27–30 nucleotide gap by repair synthesis. Repair synthesis requires DNA polymerases or , as well as the accessory replication proteins PCNA, RPA and RFC. The covalent integrity of the damaged strand is then restored by DNA ligase. Collectively, these biochemical events return the damaged DNA to its native chemistry and configuration. ERCC1, excision repair cross-complementing 1; PCNA, proliferating cell nuclear antigen; POL, polymerase; RFC, replication factor C; RPA, replication protein A; TFIIH, transcription factor IIH; XP, xeroderma pigmentosum."
"What is the definition of Hyperglycinemia, Non-Ketotic?","Nonketotic hyperglycinemia (GCE) is inherited as an autosomal recessive disorder. Most patients with GCE have a defect in the GLDC gene. The defect concerns the enzyme involved in the conversion of glycine to CO2, NH3 and hydroxymethyltetrahydrofolic acid.  Patients also have abnormally low oxalate excretion in the urine. Typical symptoms of GCE present in the first few days of life and are characterized by lethargy, hypotonia, and myoclonic jerks, and progressing to apnea, and often to death. Those who regain spontaneous respiration develop intractable seizures and profound mental retardation.  Nonketotic hyperglycinemia was originally named to distinguish it from ketotic hyperglycinemia, which is now known to be propionic academia"
What is the definition of DOPA-Responsive Dystonia?,"Dopa-responsive dystonia is a disorder that involves involuntary muscle contractions, tremors, and other uncontrolled movements (dystonia). The features of this condition range from mild to severe. This form of dystonia is called dopa-responsive dystonia because the signs and symptoms typically improve with sustained use of a medication known as L-Dopa. Over time, affected individuals often develop a group of movement abnormalities called parkinsonism. These abnormalities include unusually slow movement (bradykinesia), muscle rigidity, tremors, and an inability to hold the body upright and balanced (postural instability). Mutations in the GCH1 gene are the most common cause of dopa-responsive dystonia. Less often, mutations in the TH or SPR gene cause this condition."
What is the definition of Hyperphenylalaninemia Due to Guanosine Triphosphate Cyclohydrolase Deficiency?,"Hyperphenylalaninemia is the high presence of phenylalanine in the system/blood caused by a genetic mutation. In this case a missense error in the gene which encodes GTP cyclohydrolase. Consequently, this form of hyperphenylalaninemia is also called GTP cyclohydrolase I deficiency and/or dopa-responsive dystonia. It is an autosomal recessive mutation.The mutation results in a reduction in the production of BH4 which is a necessary component in the reaction which transforms phenylalanine to other products in the body.Common symptoms include: abnormality of eye mpvement, choreoathetosis, dysphagia, dystonia, excessive salivation, hypekinesis, lethargy, limb hyptertonia, seizures, tremor, among others."
What is the definition of Hyperphenylalaninemia Due to 6-Pyruvoyltetrahydropterin Synthase Deficiency (ptps)?,"BH4-deficient hyperphenylalaninemia has several causes. One such cause is a PTS deficiency resultant from a genetic mutation. (In particular, a mutation in the gene encoding 6-pyruvoyl-tetrahydropterin synthase.)  The mutation is autosomal recessive. Common symptoms include: muscular hypotonia, ataxia, bradykinesia, choreoathetosis, depressivity, dysphagia, hyperkinesis, hypsarrhythmia, myoclonus, and others. BH4 is a cofactor involved in many things and associated with neurotransmitter synthesis. In short, the reduction of levels of BH4 creates issues in the metabolism of phenylalanine. This cascade of reactions produces the aforementioned symptoms."
What is the definition of Hyperphenylalaninemia Due to DHPR-Deficiency?,"Hyperphenylalaninemia due to dihydropteridine reductase deficiency (DHPR) is the high presence of phenylalanine in the system/blood caused by a genetic mutation. More specificially, mutations in the QDPR gene are the root cause of the condition. One observes that such a mutation results in an error encoding a reductase enzyme, and from there a chain reaction of effects lead to the observed effects of the disease. The mutation is autosomal recessive. When tetrahydrobiopterin levels drop, the breakdown of many several amino acids, such as phenylalanine, is reduced and as a result their levels in the blood augment. Symptoms of hyperphenylalaninemia due to dihydropteridine reductase deficiency include: dysphagia, global development delay, microcephaly, and intellectual disability (among others). Treatment consists of BH4 supplements as well as other medical treatments."
What is the definition of Segawa Syndrome?,"Dopa-responsive dystonia (autosomal dominant Segawa syndrome) is caused by heterozygous mutation in the gene encoding GTP cyclohydrolase I. GTP cyclohydrolase I is rate-limiting in the conversion of GTP to tetrahydrobiopterin (BH4), the cofactor for tyrosine hydroxylase, which in turn is the rate-limiting enzyme for dopamine synthesis. Patients are characterized by childhood onset dystonia of the legs, progressing to parkinsonism and pseudo-pyramidal deficits, or in adult life with parkinsonism and pseudo-pyramidal signs.  Treatment with levodopa typically resolves the symptoms."
What is the definition of Sepiapterin Reductase Deficiency?,"Sepiapterin reductase deficiency results from a metabolic disorder; namely, the underproduction of Sepiapterin. The cause of this underproduction is an autosomal recessive genetic mutation in the SPR gene. This gene is responsible for Sepiapterin production, and naturally, when the gene malfunctions the production of this metabolite is altered leading to a range of effects on the body. In this case, some symptoms of Sepiapterin Deficiency are: motor and speech delay, axial hypotonia, dystonia, weakenss microcephaly, dysarthria, autonomic dysfunction, oculogyric crises, drowsiness, among others."
"What is the definition of Carnosinuria, Carnosinemia?",Carnosinemia is a recessive autosomal disorder caused by defects in the enzyme carnosinase. Carnosine is a dipeptide of alanine and histidine.  Patients with this disorder typically secrete large amounts of carnosine and anserine in the urine but low levels of methylhistidine.  Patients also have unusually high concentrations of homocarnosine in the cerebrospinal fluid. The condition causes a progressive neurologic disorder characterized by severe mental defect and myoclonic seizures.
"What is the definition of Tyrosinemia, Transient, of the Newborn?","A transient defect in tyrosine metabolism is a common aminoacidopathy in the premature and full-term human infant. This disorder, termed neonatal tyrosinemia, was first described by Levine and Gordon in 1939. In the intervening years other workers have studied this disorder, and have noted the concurrence of tyrosinemia and tyrosyluria. In a current survey of 15,000 infants, 6 mild tyrosinemia occurred during the first week of life in 10% of full-term infants, and severe tyrosinemia occurred in approximately 30% of premature infants. The enzymatic basis of neonatal tyrosinemia is complex and involves the susceptibility of p-hydroxyphenylpyruvic acid oxidase to inhibition in the presence of its substrate, p-hydroxyphenylpyruvic acid and derivatives. The inhibition is reversible by removal of excess substrate and by reducing agents such as ascorbic acid, 2, 6-dichiorophenolindophenol, and a number of hydroquinone and phenylenediamine compounds."
What is the definition of Galactosemia II (GALK)?,Galactokinase deficiency or Galactosemia type II is caused by mutation in the GALK1 gene on chromosome 17q24. Galactokinase deficiency is an autosomal recessive disorder which causes cataract formation in children not maintained on a lactose-free diet. Cataract formation is the result of osmotic phenomena caused by the accumulation of galactitol in the lens.
What is the definition of Galactosemia III?,"Galactosemia III (GALE deficiency or UDP-Galactose-4-Epimerase deficiency) is caused by homozygous or compound heterozygous mutation in the UDP-galactose-4-epimerase gene (GALE).  Patients with GALE deficiency may be at increased risk for cataracts. Patients also exhibit symptoms similar to classic galactosemia, including jaundice, vomiting, hypotonia, failure to thrive, hepatomegaly, moderate generalized amino aciduria and marked galactosuria. Although a galactose-free diet is recommended in galactokinase deficiency and in classic galactosemia patients with galactose epimerase deficiency cannot utilize the endogenous pathway for synthesis of UDP-galactose, making them dependent on exogenous galactose; thus, a galactose-restricted rather than a galactose-free diet is recommended in the management of this disorder."
What is the definition of Tyrosine Hydroxylase Deficiency?,"Mutations in the Tyrosine hydroxylase (TH) gene cause TH deficiency. The TH gene provides instructions for making the enzyme tyrosine hydroxylase, which takes part in the pathway that produces a group of chemical messengers called catecholamines, namely dopamine, norepinephrine and epinephrine. Dopamine transmits signals to help the brain control physical movement and emotional behavior. Norepinephrine and epinephrine are involved in the autonomic nervous system. Mutations in the TH gene result in reduced activity of the tyrosine hydroxylase enzyme. As a result, the body produces less dopamine, norepinephrine and epinephrine. These catecholamines are necessary for normal nervous system function, and changes in their levels contribute to the abnormal movements, autonomic dysfunction, and other neurological problems seen in people with TH deficiency."
What is the definition of Dopamine beta-Hydroxylase Deficiency?,"Dopamine beta-hydroxylase deficiency (or norepinephrine deficiency) is caused by mutation in the gene encoding dopamine beta-hydroxylase. Clinical features include orthostatic hypotension, ptosis, nasal stuffiness, and a neonatal history of delayed eye opening. Noradrenaline and adrenaline are generally not detectable in plasma, urine, and cerebrospinal fluid, but dopamine is increased 7- to 12-fold in plasma, 4-fold in urine, and 20-fold in CSF. Treatment with dihydroxyphenylserine has been shown to reduce symptoms and signs of postural hypotension and increase plasma levels of noradrenaline."
What is the definition of beta-Mercaptolactate-Cysteine Disulfiduria?,"Metcaptolactate-cysteine disulfiduria (MCDU) is an autosomal disorder that leads to the loss of function of the enzyme mercaptopyruvate sulfurtransferase. The condition is characterized by the urinary excretion of large amounts of a sulfur-containing amino acid, which is beta-mercaptolactate-cysteine disulfide. Patients exhibit a low IQ, grand mal seizures, flattened nasal bridge, and an excessively arched palate."
What is the definition of 5-Oxoprolinase Deficiency?,5-oxoprolinase deficiency can be caused by heterozygous or homozygous mutation in the OPLAH gene (5-Oxoprolinase).  Patients are relatively asymptomatic but they do exhibit high levels of urinary excretion of 5-oxoproline. Patients also exhibit plasma 5-oxoproline levels of about 0.18 mM or higher.  Patients tend to exhibit transient hypoglycemia.
What is the definition of gamma-Glutamyltranspeptidase Deficiency?,"Gamma-glutamyltranspeptidase deficiency is characterized by glutathionemia and glutathionuria. Gamma-glutamyltranspeptidase acts as a glutathionase and catalyzes the transfer of the glutamyl moiety of glutathione to a variety of amino acids and dipeptide acceptors. Patients with this disorder may exhibit mild mental retardation, asthma and easy bruising."
What is the definition of Malonyl-CoA Decarboxylase Deficiency?,"Malonyl CoA decarboxylase deficiency is an autosomal disorder is caused by mutation in the malonyl-CoA decarboxylase gene. The characteristic phenotype of this condition is quite variable, but may include developmental delay in early childhood, seizures, hypotonia, diarrhea, vomiting, metabolic acidosis, hypoglycemia, ketosis, abnormal urinary compounds, lactic acidemia, and hypertrophic cardiomyopathy."
What is the definition of Hypophosphatasia?,"Infantile hypophosphatasia is caused by homozygous or compound heterozygosity mutation in the gene encoding tissue-nonspecific alkaline phosphatase. It is an inborn error of metabolism characterized clinically by defective bone mineralization that can be fatal early in infancy.  Three more or less distinct types can be identified: (1) type 1 with onset in utero or in early postnatal life, craniostenosis, severe skeletal abnormalities, hypercalcemia, and death in the first year or so of life; (2) type 2 with later, more gradual development of symptoms, moderately severe 'rachitic' skeletal changes and premature loss of teeth; (3) type 3 with no symptoms, the condition being determined on routine studies. Heterozygotes excrete phosphoethanolamine in the urine and suffer early loss of teeth. Serum and urinary phosphoethanolamine are typically elevated and serum pyridoxal-PO4 concentrations are often markedly elevated."
"What is the definition of Creatine Deficiency, Guanidinoacetate Methyltransferase Deficiency?","Guanidinoacetate methyltransferase deficiency, also called GAMT deficiency, is an autosomal recessivemetabolic disorder that primarily affects the nervous system and muscles. It is the first observed disorder of creatine metabolism. This disorder usually appears in the first few months of life, when development of new motor and cognitive skills becomes delayed or stops. Eventually, affected children may lose previously acquired skills such as head control or the ability to sit unsupported. (Wikipedia) Guanidinoacetate methyltransferase (GAMT) deficiency is a good candidate disorder for newborn screening because early treatment appears to improve outcomes. (PMID: 23583224) "
What is the definition of Hyperornithinemia with Gyrate Atrophy (HOGA)?,"Gyrate atrophy of the choroid and retina (also called Gyrate atrophy, OAT deficiency, ornithine aminotransferase deficiency, ornithine keto acid aminotransferase deficiency) is an autosomal recessive disorder caused by homozygous or compound heterozygous mutation in the OAT gene (Ornithine aminotransferase).  It is clinically characterized by progressive chorioretinal degeneration, early cataract formation, and type II muscle fiber atrophy.  Ornithine levels are typically 10 to 20 times higher than normal in plasma, urine, spinal fluid, and aqueous humor.  Some cases of OAT deficiency are vitamin B6 (pyridoxine) -responsive."
What is the definition of Hyperornithinemia-Hyperammonemia-Homocitrullinuria [HHH-syndrome]?,"Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is an autosomal recessive disorder caused by a mutation in the SLC25A15 gene, which encodes the mitochondrial ornithine transporter. It is clinically characterized by mental retardation, spastic paraparesis and myoclonic seizures associated with hyperornithinemia, hyperammonemia, and homocitrullinemia. Ornithine supplementation and restricted protein intake appears to be useful in the treatment of HHH syndrome."
What is the definition of L-Arginine:Glycine Amidinotransferase Deficiency?,"Arginine:glycine amidinotransferase deficiency is an inherited disorder that primarily affects the brain. People with this disorder have mild to moderate intellectual disability and delayed speech development. Some affected individuals develop autistic behaviors that affect communication and social interaction. They may experience seizures, especially when they have a fever. Children with arginine:glycine amidinotransferase deficiency may not gain weight and grow at the expected rate (failure to thrive), and have delayed development of motor skills such as sitting and walking. Affected individuals may also have weak muscle tone and tend to tire easily."
What is the definition of Cholesteryl Ester Storage Disease?,"Lysosomal acid lipase deficiency (also known as LIPA deficiency or cholesteryl ester storage disease [CESD] or Wolman disease) is an autosomal recessive disorder caused by homozygous or compound heterozygous mutations in the LIPA gene (lysosomal acid lipase) on chromosome 10q24-q25.  Wolman disease is an early-onset fulminant disorder of infancy with massive infiltration of the liver, spleen, and other organs by macrophages filled with cholesteryl esters and triglycerides.  Death occurs early in life.  CESD is a milder, later-onset disorder with primary hepatic involvement by macrophages engorged with cholesteryl esters.  This slowly progressive visceral disease has a very wide spectrum of involvement ranging from early onset with severe cirrhosis to later onset of more slowly progressive hepatic disease with survival into adulthood. "
What is the definition of Hyper-IgD Syndrome?,"Hyperimmunoglobulinemia D with recurrent fever (commonly abbreviated as HIDS) is a periodic fever syndrome originally described in 1984 by the internist Prof. Jos van der Meer, then at Leiden University Medical Centre. No more than 300 cases have been described worldwide. HIDS is one of a number of periodic fever syndromes. It is characterised by attacks of fever, arthralgia, skin lesions including cyclical mouth ulcers, and diarrhea. Laboratory features include an acute phase response (elevated CRP and ESR) and markedly elevated IgD (and often IgA), although cases with normal IgD have been described. (Wikipedia)"
What is the definition of Mevalonic Aciduria?,"Mevalonate kinase deficiency is a condition characterized by recurrent episodes of fever, which typically begin during infancy. Each episode of fever lasts about 3 to 6 days, and the frequency of the episodes varies among affected individuals. In childhood the fevers seem to be more frequent, occurring as often as 25 times a year, but as the individual gets older the episodes occur less often. Mevalonate kinase deficiency has additional signs and symptoms, and the severity depends on the type of the condition. There are two types of mevalonate kinase deficiency: a less severe type called hyperimmunoglobulinemia D syndrome (HIDS) and a more severe type called mevalonic aciduria (MVA)."
What is the definition of Wolman Disease?,"In Wolman's disease excessive amounts of cholesterol ester in the liver are present mainly in the macrophages of the reticuloendo- thelial system. The livler in Wiolman's disease contains triglyceride at 10 to 20 times the normal concentratlon, most of whilch is present in hepatocytes. The first case of Wolman's disease was published in 1956 by M. Wolman, M.D., reporting a case of a 2 month old girl who had been admitted to the Hadassah University Hospital. Lysosomal   acid   lipase/acid   cholesteryl   ester   hydrolase (LAL/ACEH) plays an important role in cellular processing of plasma lipoproteins and thus contributes to both the homeostatic control of plasma lipoprotein levels and the prevention of cellular lipid overload. Wolman's Disease results from severely reduced levels of the enzyme lysosomal   acid   lipase/acid   cholesteryl   ester   hydrolase."
What is the definition of Xanthinuria Type I?,"Xanthinuria Type I is a condition caused by an autosomal recessive mutation. The condition was discovered (though not diagnosed) in 1817, when stones formed of almost pure xanthine were first identified by Marcet. The symptoms arise because of a malfunction in the production of xanthine oxidase. It is a rare . It is characterized by a loss of oxidase  such as in serum and the uric acid found in peepee. As a result, the opposite is true for the presence of xanthine and hypoxanthine. They will be found in the latter and former in increased quantities. Although the condition can cause a wide range of symptoms including renal xanthine stones, what occurs most of the time is that xanthinuria is asymptomatic and diagnosis is product of chance. "
What is the definition of Xanthinuria Type II?,"Xanthinuria, also known as xanthine oxidase deficiency, is a rare genetic disorder causing the accumulation of xanthine. It is caused by a deficiency of the enzyme xanthine oxidase. Classic xanthinuria is a rare metabolic defect concerning the final reactions of purine catabolism. There are two types of the disorder: type I results from xanthine dehydrogenase (XDH) deficiency, while type II is characterized by lack of both XDH and aldehyde oxidase activity. Both types are clinically similar and are characterized by elevated xanthine concentration in body fluids that can lead to xanthine crystallisation. The most common manifestation of the disease is urolithiasis, but in most cases xanthinuria remains asymptomatic and the diagnosis is accidental. "
What is the definition of gamma-Cystathionase Deficiency (CTH)?,"Cystathioninuria, also called cystathionase deficiency, is an autosomal recessive metabolic disorder that results in an excess of cystathionine in the urine. It is associated with a congenital dysfunction of the enzyme cystathionase, or acquired deficiency of vitamin B6 which is essential for the function of this enzyme. The latter is usually related to an overall deficiency of all the B-complex vitamins."
"What is the definition of Homocystinuria, Cystathionine beta-Synthase Deficiency?","Homocystinuria caused by cystathionine β-synthase (CBS) deficiency is characterized by developmental delay/intellectual disability, ectopia lentis and/or severe myopia, skeletal abnormalities (excessive height and length of the limbs), and thromboembolism. (PMID: 20301697) Classical Homocystinuria, also known as cystathionine beta synthase deficiency or CBS deficiency,[1] is an inherited disorder of the metabolism of the amino acid methionine, often involving cystathionine beta synthase. It is an inherited autosomal recessive trait, which means a child needs to inherit a copy of the defective gene from both parents to be affected. This defect leads to a multisystemic disorder of the connective tissue, muscles, CNS, and cardiovascular system. Homocystinuria represents a group of hereditary metabolic disorders characterized by an accumulation of homocysteine in the serum and an increased excretion of homocysteine in the urine. Infants appear to be normal and early symptoms, if any are present, are vague."
"What is the definition of Adrenoleukodystrophy, X-Linked?","Adrenoleukodystrophy (ALD) is an X-linked recessive transmission disease. Central nervous system signs and symptoms have been consistently more prominent than signs of adrenal involvement. Behavioral changes are the most common initial finding and range from aggressive outbursts to withdrawal. Such behavior is generally accompanied by a gradually failing memory and poor school performance. Loss of vision is an early finding in some patients and is a prominent feature at some stage in most affected individuals. The initial visual loss appears as homonomous hemianopsia in some individuals and is usually associated with intact pupillary reflexes. Optic atrophy is less common as an initial finding but eventually develops in almost all cases. Gait disturbance is also an early finding and as is stiff-legged, unsteady and accompanied by hyperreflexia. In almost all cases there is spastic quadraplegia and a variable degree of decorticate posturing. Hearing loss, dysarthria and dysphagia develop at about the same time as gait disturbance. Seizures are a typical symptom in many affected individuals in the the end stages of the disease progression."
What is the definition of Carnitine-Acylcarnitine Translocase Deficiency?,"Carnitine-acylcarnitine translocase (CACT) deficiency is a condition that prevents the body from using certain fats for energy, particularly during periods without food (fasting). Signs and symptoms of this disorder usually begin soon after birth and may include breathing problems, seizures, and an irregular heartbeat (arrhythmia). Affected individuals typically have low blood sugar (hypoglycemia) and a low level of ketones, which are produced during the breakdown of fats and used for energy. Together these signs are called hypoketotic hypoglycemia. People with CACT deficiency also usually have excess ammonia in the blood (hyperammonemia), an enlarged liver (hepatomegaly), and a weakened heart muscle (cardiomyopathy). Many infants with CACT deficiency do not survive the newborn period. Some affected individuals have a less severe form of the condition and do not develop signs and symptoms until early childhood. These individuals are at risk for liver failure, nervous system damage, coma, and sudden death."
What is the definition of Glucose-6-phosphate Dehydrogenase Deficiency?,"Glucose-6-phosphate dehydrogenase deficiency is a genetic disorder that occurs most often in males. This condition mainly affects red blood cells, which carry oxygen from the lungs to tissues throughout the body. In affected individuals, a defect in an enzyme called glucose-6-phosphate dehydrogenase causes red blood cells to break down prematurely. This destruction of red blood cells is called hemolysis. The most common medical problem associated with glucose-6-phosphate dehydrogenase deficiency is hemolytic anemia, which occurs when red blood cells are destroyed faster than the body can replace them. This type of anemia leads to paleness, yellowing of the skin and whites of the eyes (jaundice), dark urine, fatigue, shortness of breath, and a rapid heart rate. In people with glucose-6-dehydrogenase deficiency, hemolytic anemia is most often triggered by bacterial or viral infections or by certain drugs (such as some antibiotics and medications used to treat malaria). Hemolytic anemia can also occur after eating fava beans or inhaling pollen from fava plants (a reaction called favism). Glucose-6-dehydrogenase deficiency is also a significant cause of mild to severe jaundice in newborns. Many people with this disorder, however, never experience any signs or symptoms."
What is the definition of Ribose-5-phosphate Isomerase Deficiency?,"Ribose-5-phosphate isomerase (RPI) deficiency, is a genetic disorder caused by mutations in the RPIA gene that codes for RPI. RPI is an enzyme that is involved in the pentose phosphate pathway as part of carbohydrate degradation. It reversibly converts D-ribulose 5-phosphate into D-ribose 5-phosphate. In the case of this disorder, RPI functions partially in tissues, because if the gene was simply non-functional, it would likely be lethal. This means that a specific type of mutation needs to occur for this disorder to occur, leading to it being the rarest disease in the world, with only three confirmed cases. In the first known case, the patient had one allele containing a frameshift mutation, which led to a truncated protein, while the other allele contained a missense mutation. This combination meant that activity of RPI was found to vary across tissues and cell types.Characteristics of the RPI deficiency include higher ribitol and arabitol levels in a metabolic profile, as well as differences in polyol profiles. There are other symptoms, including leukoencephalopathy and neuropathy, which may be caused by a toxic accumulation of ribitol and arabitol, or a potential lack of ribose-5-phosphate in RNA synthesis."
What is the definition of Transaldolase Deficiency?,"Transaldolase deficiency, also known as Eyaid syndrome or TALDO deficiency, is a desease caused by homozygous or compound heterozygous mutations in the TALDO1 gene that encodes for transaldolase. The mutation found in one study was a base pair deletion leading to a premature truncation of the protein, preventing its activity in the cell. Other mutations reported in other studies include other deletions or homozygous base pair substitutions that cause a misfolded and non-functional protein.Transaldolase is an enzyme that reversibly converts D-erythrose 4-phosphate and fructose 6-phosphate to D-sedoheptulose 7-phosphate and D-glyceraldehyde 3-phosphate, as a part of the pentose phosphate pathway. Almost all affected patients show hepatosplenomegaly, liver dysfunction, low counts for all blood cell types, cardiac defects, and come from consanguinous families. They also show dysmorphic features, including a triangular face, low set ears, and a wide mouth with thin lips. Other signs include abnormal concentrations of polyols in urine and plasma, as well as ribose-, xylulose-, and ribulose-5-phosphate being elevated in urine."
What is the definition of 3-Hydroxyisobutyric Acid Dehydrogenase Deficiency?,3-Hydroxyisobutyric aciduria  (3-hydroxyisobutyric acid dehydrogenase deficiency) is a rare entity and affected individuals display a range of clinical manifestations including dysmorphic features and neurodevelopmental problems in the majority of patients.
What is the definition of 3-Hydroxyisobutyric Aciduria?,"3-Hydroxyisobutyric aciduria, a disorder of valine metabolism, has been found in a boy in whom the clinical picture was that of a typical organic acidemia with repeated episodes of ketoacidosis requiring admission to hospital and parenteral fluid therapy, along with impressive failure to thrive and chronic lactic acidemia. The excretion of 3-hydroxyisobutyric acid ranged from 170 to 390 mmol/mol of creatinine. The administration of valine increased this to 18,700 mmol/mol of creatinine and reproduced the clinical picture of ketoacidosis. Concentrations of free carnitine were low, and esterified carnitine was elevated. Treatment with carnitine and a diet restricted in protein appeared to be beneficial."
What is the definition of Isobutyryl-CoA Dehydrogenase Deficiency?,"Isobutyryl-CoA dehydrogenase (IBD) deficiency is a condition that disrupts the breakdown of certain proteins. Normally, proteins from food are broken down into parts called amino acids. Amino acids can be further processed to provide energy for growth and development. People with IBD deficiency have inadequate levels of an enzyme that helps break down a particular amino acid called valine. Most people with IBD deficiency are asymptomatic, which means they do not have any signs or symptoms of the condition. A few children with IBD deficiency have developed features such as a weakened and enlarged heart (dilated cardiomyopathy), weak muscle tone (hypotonia), and developmental delay. This condition may also cause low numbers of red blood cells (anemia) and very low blood levels of carnitine, which is a natural substance that helps convert certain foods into energy. The range of signs and symptoms associated with IBD deficiency remains unclear because very few affected individuals have been reported."
What is the definition of Isovaleric Acidemia?,"Isovaleric acidemia is a rare disorder in which the body is unable to process certain proteins properly. It is classified as an organic acid disorder, which is a condition that leads to an abnormal buildup of particular acids known as organic acids. Abnormal levels of organic acids in the blood (organic acidemia), urine (organic aciduria), and tissues can be toxic and can cause serious health problems. Mutations in the IVD gene cause isovaleric acidemia."
What is the definition of Fabry Disease?,"Fabry disease is an inherited disorder that results from the buildup of a particular type of fat, called globotriaosylceramide, in the body's cells. Beginning in childhood, this buildup causes signs and symptoms that affect many parts of the body. Characteristic features of Fabry disease include episodes of pain, particularly in the hands and feet (acroparesthesias); clusters of small, dark red spots on the skin called angiokeratomas; a decreased ability to sweat (hypohidrosis); cloudiness of the front part of the eye (corneal opacity); problems with the gastrointestinal system; ringing in the ears (tinnitus); and hearing loss. Fabry disease also involves potentially life-threatening complications such as progressive kidney damage, heart attack, and stroke. Some affected individuals have milder forms of the disorder that appear later in life and affect only the heart or kidneys. Fabry disease is caused by mutations in the GLA gene. "
What is the definition of Krabbe Disease?,"Krabbe disease (also called globoid cell leukodystrophy) is a degenerative disorder that affects the nervous system. It is caused by the shortage (deficiency) of an enzyme called galactosylceramidase. This enzyme deficiency impairs the growth and maintenance of myelin, the protective covering around certain nerve cells that ensures the rapid transmission of nerve impulses. Krabbe disease is part of a group of disorders known as leukodystrophies, which result from the loss of myelin (demyelination). This disorder is also characterized by the abnormal presence of globoid cells, which are globe-shaped cells that usually have more than one nucleus. The symptoms of Krabbe disease usually begin before the age of 1 year (the infantile form). Initial signs and symptoms typically include irritability, muscle weakness, feeding difficulties, episodes of fever without any sign of infection, stiff posture, and slowed mental and physical development. As the disease progresses, muscles continue to weaken, affecting the infant's ability to move, chew, swallow, and breathe. Affected infants also experience vision loss and seizures."
"What is the definition of Hyperlysinemia I, Familial?","Hyperlysinemia is an inherited condition characterized by elevated blood levels of the amino acid lysine, a building block of most proteins. Hyperlysinemia is caused by the shortage (deficiency) of the enzyme that breaks down lysine. Hyperlysinemia typically causes no health problems, and most people with elevated lysine levels are unaware that they have this condition. Rarely, people with hyperlysinemia have intellectual disability or behavioral problems. It is not clear whether these problems are due to hyperlysinemia or another cause. Mutations in the AASS gene cause hyperlysinemia."
What is the definition of Hyperlysinemia II or Saccharopinuria?,"Saccharopinuria (also known as: saccharopinemia, saccharopine dehydrogenase deficiency, and alpha-aminoadipic semialdehyde synthase deficiency, hyperlysinemia type II) is an autosomal recessive disease characterized by high concentrations of saccharopine in the plasma and urine.It is caused by the deficiency of the enzyme alpha-aminoadipic semialdehyde synthase (AASS). AASS contains a lysine ketoglutarate reductase (LKR) domain which catalyzes the conversion of lysine to saccharopine, and a saccharapine dehydrogenase (SDH) domain which catalyzes the conversion of saccharopine to alpha-aminoadipic semialdehyde. Hyperlysinemia type II is categorized by the loss in SDH activity but the preservation of significant amounts of LKR activity. This leads to the accumulation of saccharopine. The loss of both enyzmatic functions is categorized as hyperlysinemia type I."
What is the definition of D-Glyceric Acidura?,"D-glyceric aciduria is a rare inborn error of serine and fructose metabolism that was first described in 1974. Most affected individuals have presented with neurological symptoms. The molecular basis of D-glyceric aciduria is largely unknown; possible causes that have been discussed are deficiencies of D-glycerate dehydrogenase, triokinase, and D-glycerate kinase. In 1989, van Schaftingen has reported decreased D-glycerate kinase activity in the liver of a single patient with D-glyceric aciduria. Mutations in the GLYCTK gene are reported to be the cause of D-glycerate kinase deficiency. "
What is the definition of Familial Lipoprotein Lipase Deficiency?,"Hyperlipidemia, hyperlipoproteinemia, or hyperlipidaemia (British English) involves abnormally elevated levels of any or all lipids and/or lipoproteins in the blood. It is the most common form of dyslipidemia (which also includes any decreased lipid levels). Hyperlipidemias are divided in primary and secondary subtypes. Primary hyperlipidemia is usually due to genetic causes (such as a mutation in a receptor protein), while secondary hyperlipidemia arises due to other underlying causes such as diabetes. Lipid and lipoprotein abnormalities are common in the general population, and are regarded as a modifiable risk factor for cardiovascular disease due to their influence on atherosclerosis. In addition, some forms may predispose to acute pancreatitis."
"What is the definition of Glycogenosis, Type VII. Tarui Disease?","Glycogen storage disease (GSD, also glycogenosis and dextrinosis) is the result of defects in the processing of glycogen synthesis or breakdown within muscles, liver, and other cell types.[1] GSD has two classes of cause: genetic and acquired. Genetic GSD is caused by any inborn error of metabolism (genetically defective enzymes) involved in these processes. In livestock, acquired GSD is caused by intoxication with the alkaloid castanospermine."
What is the definition of Sulfite Oxidase Deficiency?,"Sulfite oxidase deficiency (SOD) is a disorder, an autosomal recessive disease. In classic SOD, it is usually identified a few days after the birth of an affected individual, and is recognizable through characteristic dysmorphic features, seizures, and other signs of progressive encephalopathy. Patients also have ocular lenses that are dislocated, and usually die within a few months of being born. In late- onset SOD, the disorder is identified only in the later months, usually 6-18 months, of the child’s life by a delay or regression of neurological progress. This disorder is very rare, but the actual prevalence is not known. It can be diagnosed through a sulfite test strip in urine or by a skin fibroblast culture, which will indicate an absence of sulfite oxidase. "
What is the definition of Monoamine Oxidase-A Deficiency (MAO-A)?,"Momoamine oxidase A (MAO-A) deficiency, or Brunner syndrome, is an X-linked recessive genetic disorder caused by a mutation in the MAOA gene that encodes for monoamine oxidase A. As such it is almost exclusively found in men.MAO-A is an enzyme that catalyzes the deamination of amines such as epinephrine, dopamine and tyramine, as part of the tyrosine metabolism pathway. In this disorder, some neurotransmitters such as serotonin and dopamine build up in the brain due to their inability to be properly metabolized. Since serotonin helps to regulate emotions and mood, with epinephrine and norepinephrine regulating stress, the unnecessary presence of the chemicals in the brain can lead to poor impulse control, aggression and other effects. The buildup of chemicals may also damage the brain, leading to a lower IQ in individuals with this disorder. In addition, foods containing the compounds that cannot be broken down, such as tyramine, can cause episodes of increased symptoms in the patients.In the subpathway that converts dopamine to homovanillic acid, there are two instances of MAO-A that are inactivated in this disorder, both in different branches. The first reaction converts dopamine to 3,4-dihydroxyphenylacetaldehyde, while the second converts 3-methoxytyramine to homovanillin. With the inactivation of MAO-A, 3-methoxytyramine builds up as there are no reactions that use it, and both of these paths lead to a decrease in the concentration of homovanillic acid, as there are no other reactions present that produce it. Another reaction, this time converting tyramine to homovanillin, is also prevented by the lack of MAO-A, which leads to an accumulation of tyramine in the body.In another branch of tyrosine metabolism, the absence of MAO-A prevents the oxidation of norepinephrine and epinephrine into 3,4-dihydroxymandelaldehyde. Its absence also prevents the oxidative deamination of metanephrine and normetanephrine into 3-methoxy-4-hydroxyphenylglycolaldehyde. As this is no longer produced, it leads to a decrease in the concentration of vanillylmandelic acid, which is produced from 3-methoxy-4-hydroxyphenylglycolaldehyde in a reaction catalyzed by aldehyde dehydrogenase."
"What is the definition of G(M2)-Gangliosidosis: Variant B, Tay-Sachs Disease?","Tay-Sachs disease is a rare inherited disorder that progressively destroys nerve cells (neurons) in the brain and spinal cord. The most common form of Tay-Sachs disease becomes apparent in infancy. Other forms of Tay-Sachs disease are very rare. Signs and symptoms can appear in childhood, adolescence, or adulthood and are usually milder than those seen with the infantile form. Characteristic features include muscle weakness, loss of muscle coordination (ataxia) and other problems with movement, speech problems, and mental illness. These signs and symptoms vary widely among people with late-onset forms of Tay-Sachs disease. Mutations in the HEXA gene cause Tay-Sachs disease."
What is the definition of Adenine Phosphoribosyltransferase Deficiency (APRT)?,"Adenine phosphoribosyltransferase (APRT) deficiency is an inherited condition that affects the kidneys and urinary tract. The most common feature of this condition is recurrent kidney stones; urinary tract stones are also a frequent symptom. Kidney and urinary tract stones can create blockages in the urinary tract, causing pain during urination and difficulty releasing urine."
What is the definition of Mitochondrial DNA Depletion Syndrome-3?,"Mitochondrial DNA depletion syndromes are a group of autosomal recessive disorders. They are characterized by decreased levels of mitochondrial DNA (mtDNA), resulting in decreased energy production. Mitochondrial DNA depletion syndrome-3 is caused by a mutation in the gene coding for deoxyguanosine kinase (DGUOK). DGUOK aids in maintaining the levels of available deoxyguanosine triphosphate (dGTP), thus the deficiency of DGUOK impairs the synthesis of dGTP. Symptoms of DGUOK deficiency can arise in the form of a multi-system disease in neonates or an isolated hepatic disease in infancy, with the former being more common. The most common cause of death in both forms is progressive hepative disease."
What is the definition of Myoadenylate Deaminase Deficiency?,"Adenosine monophosphate (AMP) deaminase deficiency is a condition that can affect the muscles used for movement (skeletal muscles). People with this condition do not make enough of an enzyme called AMP deaminase. In most people, AMP deaminase deficiency does not cause any symptoms. People who do experience symptoms typically have muscle pain (myalgia) or weakness after exercise or prolonged physical activity. They often get tired more quickly and stay tired longer than would normally be expected. Some affected individuals have more severe symptoms, but it is unclear whether these symptoms are due solely to a lack of AMP deaminase or additional factors. Muscle weakness is typically apparent beginning in childhood or early adulthood. Researchers have proposed three types of AMP deaminase deficiency, which are distinguished by their symptoms and genetic cause."
What is the definition of Carnitine Palmitoyl Transferase Deficiency I?,"Carnitine palmitoyltransferase I (CPT I) deficiency is a condition that prevents the body from using certain fats for energy, particularly during periods without food (fasting). The severity of this condition varies among affected individuals. Signs and symptoms of CPT I deficiency often appear during early childhood. Affected individuals usually have low blood sugar (hypoglycemia) and a low level of ketones, which are produced during the breakdown of fats and used for energy. Together these signs are called hypoketotic hypoglycemia. People with CPT I deficiency can also have an enlarged liver (hepatomegaly), liver malfunction, and elevated levels of carnitine in the blood. Carnitine, a natural substance acquired mostly through the diet, is used by cells to process fats and produce energy. Individuals with CPT I deficiency are at risk for nervous system damage, liver failure, seizures, coma, and sudden death. Mutations in the CPT1A gene cause CPT I deficiency."
What is the definition of Long Chain Acyl-CoA Dehydrogenase Deficiency (LCAD)?,"Very Long Chain Acyl CoA Dehydrogenase Deficiency (VLCADD) is a rare disorder that is inherited through an autosomal recessive trait, and prevents the body from properly metabolizing very long chain fatty acids. This disorder occurs in the mitochondria, where the metabolization of fatty acids takes place. Early-onset VLCADD patients usually begin to exhibit symptoms just days or weeks after birth. Hypoglycemia, lethargy and irritability are symptoms associated with this disorder. Patients will also be at risk for hypertrophic cardiomyopathy and other heart conditions from age two months to two years. It can be diagnosed through a research of family history and generally a urine analysis will reveal that the patient has reduced of absent ketone bodies. To help control acute episodes, treatment includes maintaining a high carbohydrate and low fat diet, and avoiding fasting for more than 12 hours. "
What is the definition of Very-Long-Chain Acyl-CoA Dehydrogenase Deficiency (VLCAD)?,"Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of VLCAD deficiency typically appear during infancy or early childhood and can include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. Affected individuals are also at risk for serious complications such as liver abnormalities and life-threatening heart problems. When symptoms begin in adolescence or adulthood, they tend to be milder and usually do not involve the heart. Problems related to VLCAD deficiency can be triggered by periods of fasting, illness, and exercise. This disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections."
What is the definition of Carnitine Palmitoyl Transferase Deficiency II?,"Carnitine palmitoyltransferase II (CPT II) deficiency is a disorder of long-chain fatty-acid oxidation. The three clinical presentations are: lethal neonatal form, severe infantile hepatocardiomuscular form, and myopathic form that is usually mild and can manifest from infancy to adulthood. While the former two are severe multisystemic diseases characterized by liver failure with hypoketotic hypoglycemia, cardiomyopathy, seizures, and early death, the latter is characterized by exercise-induced muscle pain and weakness, sometimes associated with myoglobinuria. The myopathic form of CPT II deficiency is the most common disorder of lipid metabolism affecting skeletal muscle and is the most frequent cause of hereditary myoglobinuria. Males are more likely to be affected than females."
What is the definition of Medium Chain Acyl-CoA Dehydrogenase Deficiency (MCAD)?,"Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of MCAD deficiency typically appear during infancy or early childhood and can include vomiting, lack of energy (lethargy), and low blood sugar (hypoglycemia). In rare cases, symptoms of this disorder first appear during adulthood. People with MCAD deficiency are at risk for serious complications such as seizures, breathing difficulties, liver problems, brain damage, coma, and sudden death.Problems related to MCAD deficiency can be triggered by periods of fasting or by illnesses such as viral infections. This disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections."
What is the definition of Long-Chain-3-Hydroxyacyl-CoA Dehydrogenase Deficiency (LCHAD)?,"Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency is a rare condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of LCHAD deficiency typically appear during infancy or early childhood and can include feeding difficulties, lack of energy (lethargy), low blood sugar (hypoglycemia), weak muscle tone (hypotonia), liver problems, and abnormalities in the light-sensitive tissue at the back of the eye (retina). Later in childhood, people with this condition may experience muscle pain, breakdown of muscle tissue, and a loss of sensation in their arms and legs (peripheral neuropathy). Individuals with LCHAD deficiency are also at risk for serious heart problems, breathing difficulties, coma, and sudden death. Problems related to LCHAD deficiency can be triggered by periods of fasting or by illnesses such as viral infections. This disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. Mutations in the HADHA gene cause LCHAD deficiency."
What is the definition of Trifunctional Protein Deficiency?,"Trifunctional protein deficiency is a condition caused by mutations in the genes HADHA and HADHB. The enzyme affected is required to metabolize long-chain fatty acids, which makes a patients ability to convert fats to energy very difficult. This is exacerbated by periods without food. The symptoms associated with this disorder differ depending on when they appear in a patient. In infancy, symptoms would include lethargy, hypoglycaemia and hypotonia. Infants are also at higher risk for sudden death and heart problems. Later onset trifunctional protein deficiency symptoms also include hypotonia, but also include breakdown of muscle tissue and peripheral neuropathy. Treatment includes a low-fat, high-carbohydrate diet and avoiding fasting, as this can induce symptoms of this condition. "
What is the definition of Congenital Lactic Acidosis?,"Mitochondrial DNA depletion syndrome-9 is a severe autosomal recessive disorder characterized by infantile onset of hypotonia, lactic acidosis, severe psychomotor retardation, progressive neurologic deterioration, and excretion of methylmalonic acid. Some patients die in early infancy (summary by Rouzier et al., 2010)."
What is the definition of Fumarase Deficiency?,"Fumarase deficiency (or fumaric aciduria), also known as ""Polygamist Down's"", is an autosomal recessive metabolic disorder characterized by a deficiency of the enzyme fumarate hydratase, which is indicated by a build up of fumaric acid in the urine. (Wikipedia) Fumarase deficiency is a severe autosomal recessive metabolic disorder characterized by early-onset hypotonia, profound psychomotor retardation, and brain abnormalities, such as agenesis of the corpus callosum, gyral defects, and ventriculomegaly. Many patients show neonatal distress, metabolic acidosis, and/or encephalopathy (summary by Kerrigan et al., 2000 and Mroch et al., 2012)."
What is the definition of Mitochondrial Complex II Deficiency?,"Mitochondrial complex II deficiency is a rare form of mitochondrial disease, accounting for approximately 2% of all respiratory chain deficiency diagnoses. The succinate dehydrogenase (SDH) genes (SDHA, SDHB, SDHC and SDHD) are autosomally-encoded and transcribe the conjugated heterotetramers of complex II via the action of two known assembly factors (SDHAF1 and SDHAF2). Only a handful of reports describe inherited SDH gene defects as a cause of paediatric mitochondrial disease, involving either SDHA (Leigh syndrome, cardiomyopathy) or SDHAF1 (infantile leukoencephalopathy). However, all four SDH genes, together with SDHAF2, have known tumour suppressor functions, with numerous germline and somatic mutations reported in association with hereditary cancer syndromes, including paraganglioma and pheochromocytoma."
What is the definition of 2-Ketoglutarate Dehydrogenase Complex Deficiency?,"2-Ketoglutarate dehydrogenase complex deficiency is a rare autosomal recessive disease. 2-ketoglutarate dehydrogenase is an enzyme of the Krebs cycle that catalyzes the oxidation of alpha-ketoglutarate to succinyl CoA. The deficiency of 2-Ketoglutarate dehydrogenase complex results in the disorder of Krebs cycle with accumulation of succinyl CoA. The primary manifestations include developmental delay, ataxia, opisthotonus, seizure and other neurological symptoms. "
What is the definition of Pyruvate Dehydrogenase Deficiency (E3)?,"DLD deficiency is an autosomal recessive metabolic disorder characterized biochemically by a combined deficiency of the branched-chain alpha-keto acid dehydrogenase complex (BCKDC), pyruvate dehydrogenase complex (PDC), and alpha-ketoglutarate dehydrogenase complex (KGDC). This is the result of E3 being a common component of all 3 mitochondrial multienzyme complexes. Clinically, affected individuals have lactic acidosis and neurologic deterioration due to sensitivity of the central nervous system to defects in oxidative metabolism. E3 deficiency is often associated with increased urinary excretion of alpha-keto acids, such as pyruvate (summary by Hong et al., 1996). E3 deficiency can also be associated with increased concentrations of branched-chain amino acids, as observed in maple syrup urine disease (MSUD; 248600), and is sometimes referred to as 'MSUD type III,' although patients with E3 deficiency have additional biochemical defects (Chuang and Shih, 2001; Robinson, 2001)."
What is the definition of Pyruvate Dehydrogenase Deficiency (E2)?,"Pyruvate Dehydrogenase (PDH) Deficiency is an X linked disease where individuals have a reduced number of functioning PDH complexes ultimately affecting the mitochondria’s energy metabolism. In a healthy individual, PDH complex catalyzes the conversion of pyruvate to acetyl coenzyme A, therefore PDH deficiency can cause the accumulation of excess pyruvate and lactic acid. PDH deficiency presents itself in a variety of ways, however since the brain obtains most of it’s energy from aerobic oxidation of glucose, all PDH deficient individuals have some degree of neurological impairment. Other symptoms range from fatal lactic acidosis in the newborns, chronic neurodegenerative conditions, brain lesions, cerebral atrophy and much more.Due to the fatal nature of the disease many with this condition do not live past childhood, however there are some that survive to adolescents and adulthood. Treatments have tried to minimize systemic lactic acid accumulation by feeding patients high fat/low carbohydrate diets. However, this does not reverse neurological structural damage already present and therefore does little to influence the end results."
"What is the definition of Glycogenosis, Type III. Cori Disease, Debrancher Glycogenosis?","Glycogen storage disease type III (also known as GSDIII or Cori disease) is an inherited disorder caused by the buildup of a complex sugar called glycogen in the body's cells. The accumulated glycogen is structurally abnormal and impairs the function of certain organs and tissues, especially the liver and muscles. GSDIII is divided into types IIIa, IIIb, IIIc, and IIId, which are distinguished by their pattern of signs and symptoms. GSD types IIIa and IIIc mainly affect the liver and muscles, and GSD types IIIb and IIId typically affect only the liver. It is very difficult to distinguish between the types of GSDIII that affect the same tissues. GSD types IIIa and IIIb are the most common forms of this condition."
"What is the definition of Glycogenosis, Type IV. Amylopectinosis, Anderson Disease?","Glycogen storage disease type IV (GSD IV) is an inherited disorder caused by the buildup of a complex sugar called glycogen in the body's cells. The accumulated glycogen is structurally abnormal and impairs the function of certain organs and tissues, especially the liver and muscles. There are five types of GSD IV, which are distinguished by their severity, signs, and symptoms. Mutations in the GBE1 gene cause GSD IV."
"What is the definition of Glycogenosis, Type VI. Hers Disease?",Glycogen storage disease type VI (also known as GSDVI or Hers disease) is an inherited disorder caused by an inability to break down a complex sugar called glycogen in liver cells. A lack of glycogen breakdown interferes with the normal function of the liver. The signs and symptoms of GSDVI typically begin in infancy to early childhood. The first sign is usually an enlarged liver (hepatomegaly). Affected individuals may also have low blood sugar (hypoglycemia) or a buildup of lactic acid in the body (lactic acidosis) during prolonged periods without food (fasting). The signs and symptoms of GSDVI tend to improve with age; most adults with this condition do not have any related health problems.
What is the definition of Mucopolysaccharidosis VII. Sly Syndrome?,"Mucopolysaccharidosis type VII (MPS VII), also known as Sly syndrome, is a progressive condition that affects most tissues and organs. The severity of MPS VII varies widely among affected individuals. The features of MPS VII include a large head (macrocephaly), a buildup of fluid in the brain (hydrocephalus), distinctive-looking facial features that are described as ""coarse,"" and a large tongue (macroglossia). Affected individuals also frequently develop an enlarged liver and spleen (hepatosplenomegaly), heart valve abnormalities, and a soft out-pouching around the belly-button (umbilical hernia) or lower abdomen (inguinal hernia). MPS VII causes various skeletal abnormalities that become more pronounced with age, including short stature and joint deformities (contractures) that affect mobility. Mutations in the GUSB gene cause MPS VII."
What is the definition of Sucrase-Isomaltase Deficiency?,"Congenital sucrase-isomaltase deficiency is a disorder that affects a person's ability to digest certain sugars. People with this condition cannot break down the sugars sucrose and maltose. Sucrose (a sugar found in fruits, and also known as table sugar) and maltose (the sugar found in grains) are called disaccharides because they are made of two simple sugars. Disaccharides are broken down into simple sugars during digestion. Sucrose is broken down into glucose and another simple sugar called fructose, and maltose is broken down into two glucose molecules. People with congenital sucrase-isomaltase deficiency cannot break down the sugars sucrose and maltose, and other compounds made from these sugar molecules (carbohydrates). Congenital sucrase-isomaltase deficiency usually becomes apparent after an infant is weaned and starts to consume fruits, juices, and grains. After ingestion of sucrose or maltose, an affected child will typically experience stomach cramps, bloating, excess gas production, and diarrhea. These digestive problems can lead to failure to gain weight and grow at the expected rate (failure to thrive) and malnutrition. Most affected children are better able to tolerate sucrose and maltose as they get older."
"What is the definition of Primary Hyperoxaluria II, PH2?",Primary hyperolaria type 2 (PH2) is a rare condition resulting from glyoxylate reductase/hydroxypyruvate reductase (GR/HPR) enzyme deficiency. PH2 results in calcium oxalate (also known as oxalic acid) deposits and end-stage renal disease. These deposits may cause kidney damage or failure. 
What is the definition of Pyruvate Kinase Deficiency?,"Pyruvate kinase deficiency is a genetic disorder. It affects red blood cells in the body. Patients are affected by a condition called chronic hemolytic anemia, which is where red blood cells undergo hemolysis before they are meant to which causes anemia in the patient. Symptoms of this condition can include jaundice, fatigue, dyspnea and splenomegaly. Gallstones are also common to patients with this disorder. This disorder is diagnosed through genetic testing. In mild cases, no treatment is required. Patients with more severe cases may require blood transfusions, and occasionally the spleen is removed to aid with the reduction of red blood cell destruction. "
What is the definition of Phosphoenolpyruvate Carboxykinase Deficiency 1 (PEPCK1)?,"Phosphoenolpyruvate carboxykinase deficiency 1 (pepck1) is a rare congenital metabolic disease caused by mutation of the phosphoenolpyruvate carboxykinase gene. Phosphoenolpyruvate carboxykinase (PEPCK) is an enzyme in the lyase family used in the metabolic pathway of gluconeogenesis. It converts oxaloacetic acid into phosphoenolpyruvate and carbon dioxide. Deficiency of Phosphoenolpyruvate carboxykinase results in metabolic disorder with impaired gluconeogenesis. The clinical characteristics include hypotonia, failure to thrive, hepatomegaly, lactic acidosis and hypoglycemia."
What is the definition of Fructosuria?,"Essential fructosuria is a benign, asymptomatic defect of intermediary metabolism characterized by the intermittent appearance of fructose in the urine (summary by Bonthron et al., 1994). Essential fructosuria caused by a deficiency of the enzyme hepatic fructokinase is a clinically benign condition characterized by the incomplete metabolism of fructose in the liver, leading to its excretion in urine. Essential fructosuria is a genetic condition that is inherited in an autosomal recessive manner.Mutations in the KHK gene, located on chromosome 2p23.3-23.2 are responsible."
"What is the definition of Fructose-1,6-diphosphatase Deficiency?","Fructose-1,6-bisphosphatase (FBPase) deficiency is an autosomal, recessively inherited disease that progresses with severe hypoglycemia, and metabolic attacks result in a defect in gluconeogenesis. If not appropriately treated, and if fructose is not excluded from the diet, the outcome could be fatal."
What is the definition of Triosephosphate Isomerase Deficiency?,"Triosephosphate isomerase deficiency is a genetic disorder caused by a mutation in the TPI1 gene. The mutation of this gene causes the production of enzymes that are unstable or enzymes that have reduced activity. This means that cells have reduced energy supplies as glycolysis is compromised. This disorder causes anemia, movement problems and muscle weakness. As a result of the lack of red blood cells to carry oxygen through the body, patients may experience fatigue and shortness of breath. Movement problems appear in early infancy, typically before the age of 2 in patients with this disorder. Treatment includes blood transfusions. "
"What is the definition of Multiple Carboxylase Deficiency, Neonatal or Early Onset Form?","Holocarboxylase synthetase deficiency is an inherited disorder in which the body is unable to use the vitamin biotin effectively. This disorder is classified as a multiple carboxylase deficiency, a group of disorders characterized by impaired activity of certain enzymes that depend on biotin. The signs and symptoms of holocarboxylase synthetase deficiency typically appear within the first few months of life, but the age of onset varies. Affected infants often have difficulty feeding, breathing problems, a skin rash, hair loss (alopecia), and a lack of energy (lethargy). Immediate treatment and lifelong management with biotin supplements may prevent many of these complications. If left untreated, the disorder can lead to delayed development, seizures, and coma. These medical problems may be life-threatening in some cases."
What is the definition of Aromatase Deficiency?,"Aromatase deficiency is a rare autosomal recessive disorder caused by mutations in the CYP19A1 gene and characterized by lack of conversion of androgens to estrogens. It presents with virilization of pregnant mothers during the antenatal period, and virilization of female fetuses at birth. Affected subjects of either gender later manifest with features of estrogen deficiency and androgen excess."
What is the definition of 17-alpha-Hydroxylase Deficiency (CYP17)?,"Congenital adrenal hyperplasia (CAH) refers to any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of cortisol from cholesterol by the adrenal glands (steroidogenesis). Most of these conditions involve excessive or deficient production of sex steroids and can alter development of primary or secondary sex characteristics in some affected infants, children, or adults."
What is the definition of Succinic Semialdehyde Dehydrogenase Deficiency?,"Succinic Semialdehyde Dehydrogenase (SSADH) deficiency is a rare autosomal recessive inherited disorder affecting the metabolism of γ-aminobutyric acid (GABA). With reduced GABA activity, oxidation of succinic semialdehyde (SSA) to succinic acid is impaired causing a build up of SSA and ultimately it’s downstream metabolite γ-hydroxybutyric acid (GHB). Symptoms of SSADH deficiency are primarily neuropsychiatric including developmental delays, hypotonia, expressive language impairment, seizures, difficulty coordinating movements (ataxia), decreased reflexes (hyporeflexia), and other behavioral issues. Patients with SSADH deficiency have elevated levels of GHB in urine, however this method is not a definitive diagnosis due to the potential volatilization of acidified urine and the use of GHB as a drug. Instead SSADH can be confirmed suing enzyme analysis in leukocytes and molecular genetic analysis of the Aldh5a1 gene at chromosome 6p22."
What is the definition of Short-Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency (SCHAD)?,"3-hydroxyacyl-CoA dehydrogenase deficiency is an inherited condition that prevents the body from converting certain fats to energy, particularly during prolonged periods without food (fasting). Initial signs and symptoms of this disorder typically occur during infancy or early childhood and can include poor appetite, vomiting, diarrhea, and lack of energy (lethargy). Affected individuals can also have muscle weakness (hypotonia), liver problems, low blood sugar (hypoglycemia), and abnormally high levels of insulin (hyperinsulinism). Mutations in the HADH gene cause 3-hydroxyacyl-CoA dehydrogenase deficiency."
What is the definition of Succinyl CoA: 3-Ketoacid CoA Transferase Deficiency?,"Succinyl CoA: 3-Ketoacid CoA Transferase (SCOT) deficiency is a rare inherited metabolic disorder causing reduction of ketone body utilization. In normal functioning patients, ketone bodies such as Acetoacetate (AcAc) and 3‐hydroxybutyrate (3HB) are metabolized inside the liver from free fatty acids. Next, ketone bodies are transported to extrahepatic tissues via the blood stream. Once in extrahepatic tissues, SCOT converts AcAc to acetoacetyl‐CoA and T2 cleaves acetoacetyl‐CoA into acetyl‐CoA. This process is crucial for producing alternative energy sources to glucose in order to maintain blood glucose levels. Patients with SCOT deficiency have this process disturbed and ketoacidosis which is the acidification of the bloodstream due to excess ketone body accumulation, can occur. Current treatments include avoiding actions that could onset ketoacidosis such as fasting and early infusion of glucose.The severity of SCOT deficiency differs from patient to patient. Some exhibit severe genotypes where ketones are always in abundance in the body, while others could have mild genotypes with no preeminent ketosis however both could exhibit ketoacidotic episodes."
"What is the definition of Homocystinuria-Megaloblastic Anemia Due to Defect in Cobalamin Metabolism, cblG Complementation Type?","Homocystinuria and megaloblastic anemia is an autosomal recessive inborn error of metabolism resulting from defects in the cobalamin (vitamin B12)-dependent pathway that converts homocysteine to methionine, which is catalyzed by methionine synthase. Clinical features are somewhat variable, but include delayed psychomotor development, megaloblastic anemia, homocystinuria, and hypomethioninemia, all of which respond to cobalamin supplementation. Methylmalonic aciduria is not present. Two complementation groups have been described based on fibroblast studies: CblE (236270) and CblG (Watkins and Rosenblatt, 1988). Most patients present in early infancy, but some patients with CblG have shown later onset (Outteryck et al., 2012). Cells from patients with CblE fail to incorporate methyltetrahydrofolate into methionine in whole cells, but cell extracts show normal methionine synthase activity in the presence of a reducing agent. Cells from patients with CblG have defects in the methionine synthase enzyme under both conditions (summary by Leclerc et al., 1996). CblE is caused by mutation in the MTRR gene (602568)."
What is the definition of Pyridoxine Dependency with Seizures?,"Pyridoxine-dependent epilepsy is a condition that involves seizures beginning in infancy or, in some cases, before birth. Those affected typically experience prolonged seizures lasting several minutes (status epilepticus). These seizures involve muscle rigidity, convulsions, and loss of consciousness (tonic-clonic seizures). Additional features of pyridoxine-dependent epilepsy include low body temperature (hypothermia), poor muscle tone (dystonia) soon after birth, and irritability before a seizure episode. In rare instances, children with this condition do not have seizures until they are 1 to 3 years old. Anticonvulsant drugs, which are usually given to control seizures, are ineffective in people with pyridoxine-dependent epilepsy. Instead, people with this type of seizure are medically treated with large daily doses of pyridoxine (a type of vitamin B6 found in food). If left untreated, people with this condition can develop severe brain dysfunction (encephalopathy). Even though seizures can be controlled with pyridoxine, neurological problems such as developmental delay and learning disorders may still occur."
What is the definition of Fanconi-Bickel Syndrome?,"Fanconi-Bickel syndrome (FBS) is a rare autosomal recessive disorder of carbohydrate metabolism recently demonstrated to be caused by mutations in Glut2, the gene for the glucose transporter protein 2 expressed in liver, pancreas, intestine and kidney. The disease was first described in a 3-year-old Swiss boy in 1949. "
"What is the definition of Glycogenosis, Type IB?","Glycogen storage disease type I (also known as GSDI or von Gierke disease) is an inherited disorder caused by the buildup of a complex sugar called glycogen in the body's cells. The accumulation of glycogen in certain organs and tissues, especially the liver, kidneys, and small intestines, impairs their ability to function normally. People with GSDI may experience delayed puberty. Beginning in young to mid-adulthood, affected individuals may have thinning of the bones (osteoporosis), a form of arthritis resulting from uric acid crystals in the joints (gout), kidney disease, and high blood pressure in the blood vessels that supply the lungs (pulmonary hypertension). Females with this condition may also have abnormal development of the ovaries (polycystic ovaries). In affected teens and adults, tumors called adenomas may form in the liver. Adenomas are usually noncancerous (benign), but occasionally these tumors can become cancerous (malignant). Researchers have described two types of GSDI, which differ in their signs and symptoms and genetic cause. These types are known as glycogen storage disease type Ia (GSDIa) and glycogen storage disease type Ib (GSDIb). Two other forms of GSDI have been described, and they were originally named types Ic and Id. However, these types are now known to be variations of GSDIb; for this reason, GSDIb is sometimes called GSD type I non-a."
"What is the definition of Glycogenosis, Type IC?","Glycogen storage disease type I (also known as GSDI or von Gierke disease) is an inherited disorder caused by the buildup of a complex sugar called glycogen in the body's cells. The accumulation of glycogen in certain organs and tissues, especially the liver, kidneys, and small intestines, impairs their ability to function normally. People with GSDI may experience delayed puberty. Beginning in young to mid-adulthood, affected individuals may have thinning of the bones (osteoporosis), a form of arthritis resulting from uric acid crystals in the joints (gout), kidney disease, and high blood pressure in the blood vessels that supply the lungs (pulmonary hypertension). Females with this condition may also have abnormal development of the ovaries (polycystic ovaries). In affected teens and adults, tumors called adenomas may form in the liver. Adenomas are usually noncancerous (benign), but occasionally these tumors can become cancerous (malignant)."
What is the definition of 11-beta-Hydroxylase Deficiency (CYP11B1)?,"Congenital adrenal hyperplasia (CAH) due to 11-beta-hydroxylase deficiency is one of a group of disorders (collectively called congenital adrenal hyperplasia) that affect the adrenal glands. The adrenal glands are located on top of the kidneys and produce a variety of hormones that regulate many essential functions in the body. In people with CAH due to 11-beta-hydroxylase deficiency, the adrenal glands produce excess androgens, which are male sex hormones. There are two types of CAH due to 11-beta-hydroxylase deficiency, the classic form and the non-classic form. The classic form is the more severe of the two types."
What is the definition of 21-Hydroxylase Deficiency (CYP21)?,"Congenital adrenal hyperplasia (CAH) refers to any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of cortisol from cholesterol by the adrenal glands (steroidogenesis). 21-hydroxylase deficiency is an inherited disorder that affects the adrenal glands. The adrenal glands are located on top of the kidneys and produce a variety of hormones that regulate many essential functions in the body. In people with 21-hydroxylase deficiency, the adrenal glands produce excess androgens, which are male sex hormones. There are three types of 21-hydroxylase deficiency. Two types are classic forms, known as the salt-wasting and simple virilizing types. The third type is called the non-classic type. The salt-wasting type is the most severe, the simple virilizing type is less severe, and the non-classic type is the least severe form."
What is the definition of Corticosterone Methyl Oxidase I Deficiency (CMO I)?,"Corticosterone methyloxidase type I (CMO-I) deficiency is an autosomal recessively inherited disorder causing congenital hypoaldosteronism due to defects in aldosterone synthase (P450aldo), the enzyme that converts 11-deoxycorticosterone to corticosterone, 18-hydroxycorticosterone, and aldosterone."
What is the definition of Corticosterone Methyl Oxidase II Deficiency (CMO II)?,"CMO type II deficiency is an autosomal recessive disorder caused by a defect in the final biochemical step of aldosterone biosynthesis, the 18-hydroxylation of 18-hydroxycorticosterone (18-OHB) to aldosterone. This enzymatic defect results in decreased aldosterone and salt-wasting associated with an increased serum ratio of 18-OHB to aldosterone. In CMO II deficiency, aldosterone can be low or normal, but at the expense of increased secretion of 18-OHB. These patients have a low ratio of corticosterone to 18-OHB (Portrat-Doyen et al., 1998). The CYP11B2 gene product also catalyzes an earlier step in aldosterone biosynthesis: the 18-hydroxylation of corticosterone to 18-OHB. A defect in that enzymatic step results in CMO type I deficiency (204300), an allelic disorder with an overlapping phenotype but distinct biochemical features. In CMO I deficiency, aldosterone is undetectable, whereas its immediate precursor, 18-OHB, is low or normal (Portrat-Doyen et al., 1998)."
What is the definition of Congenital Disorder of Glycosylation CDG-IId?,"Congenital disorders of glycosylation (CDGs) are a genetically heterogeneous group of autosomal recessive disorders caused by enzymatic defects in the synthesis and processing of asparagine (N)-linked glycans or oligosaccharides on glycoproteins. These glycoconjugates play critical roles in metabolism, cell recognition and adhesion, cell migration, protease resistance, host defense, and antigenicity, among others. CDGs are divided into 2 main groups: type I CDGs (see, e.g., CDG1A, 212065) comprise defects in the assembly of the dolichol lipid-linked oligosaccharide (LLO) chain and its transfer to the nascent protein, whereas type II CDGs refer to defects in the trimming and processing of the protein-bound glycans either late in the endoplasmic reticulum or the Golgi compartments. The biochemical changes of CDGs are most readily observed in serum transferrin (TF; 190000), and the diagnosis is usually made by isoelectric focusing of this glycoprotein (reviews by Marquardt and Denecke, 2003; Grunewald et al., 2002)."
What is the definition of GLUT-1 Deficiency Syndrome?,"GLUT1 deficiency syndrome is a disorder that primarily affects the brain. Affected individuals generally have seizures beginning in the first few months of life. Babies with GLUT1 deficiency syndrome have a normal head size at birth, but growth of the brain and skull is often slow, in severe cases resulting in an abnormally small head size (microcephaly). People with GLUT1 deficiency syndrome may have developmental delay or intellectual disability. They may also have other neurological problems, such as stiffness caused by abnormal tensing of the muscles (spasticity), difficulty in coordinating movements (ataxia), and speech difficulties (dysarthria). Some experience episodes of confusion, lack of energy (lethargy), headaches, muscle twitches (myoclonus), or involuntary irregular eye movements, particularly before meals."
"What is the definition of Glycogenosis, Type IA. Von Gierke Disease?","Glycogen storage disease type I (also known as GSDI or von Gierke disease) is an inherited disorder caused by the buildup of a complex sugar called glycogen in the body's cells. The accumulation of glycogen in certain organs and tissues, especially the liver, kidneys, and small intestines, impairs their ability to function normally. Researchers have described two types of GSDI, which differ in their signs and symptoms and genetic cause. These types are known as glycogen storage disease type Ia (GSDIa) and glycogen storage disease type Ib (GSDIb). Two other forms of GSDI have been described, and they were originally named types Ic and Id. However, these types are now known to be variations of GSDIb; for this reason, GSDIb is sometimes called GSD type I non-a. Mutations in two genes, G6PC and SLC37A4, cause GSDI."
What is the definition of Joubert Syndrome?,"Joubert syndrome is a disorder that affects many parts of the body. The signs and symptoms of this condition vary among affected individuals, even among members of the same family. The hallmark feature of Joubert syndrome is a brain abnormality called the molar tooth sign, which can be seen on brain imaging studies such as magnetic resonance imaging (MRI). This sign results from the abnormal development of regions near the back of the brain called the cerebellar vermis and the brainstem. The molar tooth sign got its name because the characteristic brain abnormalities resemble the cross-section of a molar tooth when seen on an MRI."
What is the definition of Blue Diaper Syndrome?,"Blue diaper syndrome is a rare, autosomal recessive metabolic disorder characterized in infants by bluish urine-stained diapers. It is caused by a defect in tryptophan absorption. Bacterial degradation of tryptophan in the intestine leads to excessive indole production and thus to indicanuria which, on oxidation to indigo blue, causes a peculiar bluish discoloration of the diaper. Symptoms typically include digestive disturbances, fever and visual problems."
What is the definition of Lysinuric Protein Intolerance (LPI)?,"Lysinuric protein intolerance is a disorder caused by the body's inability to digest and use certain protein building blocks (amino acids), namely lysine, arginine, and ornithine. Because the body cannot effectively break down these amino acids, which are found in many protein-rich foods, nausea and vomiting are typically experienced after ingesting protein. Mutations in the SLC7A7 gene cause lysinuric protein intolerance. The SLC7A7 gene provides instructions for producing a protein called y+L amino acid transporter 1 (y+LAT-1), which is involved in transporting lysine, arginine, and ornithine between cells in the body."
What is the definition of Coagulation ?,"Blood coagulation can be initiated by either an extrinsic or an intrinsic pathway, resulting in a cascade of serine protease activation that ultimately leads to the formation of thrombin, which converts soluble fibrinogen to an insoluble fibrin clot. The extrinsic, or tissue factor, pathway is initiated upon vascular injury, when the membrane-bound protein tissue factor (TF) comes into contact with factor VII or VIIa in plasma. The TF-VIIa complex is the strongest known activator of the coagulation cascade, and converts factors IX and X to IXa and Xa, respectively. Factors VII, IX, and X are vitamin-K-dependent proteins produced in the liver. In the intrinsic, or contact, pathway, injury exposes collagen to the bloodstream where is binds to factor XII and activates it to XIIa. Factor XIIa converts prekallikrein to kallikrein and factor XI to XIa. Both the extrinsic and intrinsic pathways result in the activation of factor IX to IXa, which forms the 'tenase' complex with factor VIIIa, calcium and phospholipids. This complex converts factor X to Xa and is important in haemostasis. Factor Xa complexes with factor Va (which functions as a non-enzymatic cofactor), calcium and a phospholipid membrane surface to form what is called the prothrombinase complex, which converts prothrombin to thrombin. Thrombin converts soluble fibrinogen to insoluble fibrin polymer, which is stabilized by cross-linking by coagulation factor XIIIa."
What is the definition of Angiotensin Metabolism?,"Angiotensin is a peptide hormone that is part of the renin-angiotensin system responsible for regulating fluid homeostasis and blood pressure.   It is involved in various means to increase the body's blood pressure, hence why it is a target for many pharmceutical drugs that treat hypertension and cardiac conditions.  Angiotensin II, the primary agent to inducing an increased blood pressure, is formed in the general circulation when it is cleaved from a string of precursor molecules.  Angiotensinogen is converted into angiotensin I with the action of renin, an enzyme secreted from the kidneys.  From there, angiotensin I is converted to the central agent, angiotensin II, with the aid of angiotensin-converting enzyme (ACE) so that it is available in the circulation to act on numerous areas in the body when an increase in blood pressure is needed.  Angiotensin II can act directly on receptors on the smooth muscle cells of the tunica media layer in the blood vessel to induce vasoconstriction and a subsequent increase in blood pressure.  However, it can also influence the blood pressure by aiding in an increase of the circulating blood volume.  Angiotensin II can cause vasopressin to be released, which is a hormone involved in regulating water reabsorption.  Vasopressin is created in the supraoptic nuclei and they travel down the neurosecretory neuron axon to be stored in the neuronal terminals within the posterior pituitary.  Angiotensin II in the cerebral circulation triggers the release of vasopressin from the posterior pituitary gland.  From there, vasopressin enters into the systemic blood circulation where it eventually binds to receptors on epithelial cells in the collecting ducts of the nephron.   The binding of vasopressin causes vesicles of epithelial cells to fuse with the plasma membrane.  These vesicles contain aquaporin II, which are proteins that act as water channels once they have bound to the plasma membrane.  As a result, the permeability of the collecting duct changes to allow for water reabsorption back into the blood circulation.  Angiotensin II also has an effect on the hypothalmus, where it helps trigger a thirst sensation.  Correspondingly, there will be an increase in oral water uptake into the body, which would then also increase the circulating blood volume.  Another way that angiotensin II helps increase the blood volume is by acting on the adrenal cortex to stimulate aldosterone release, which is responsible for increasing sodium reuptake in the distal convoluted tubules and the collecting duct.  It is formed when angiotensin II binds to receptors on the zona glomerulosa cells in the adrenal cortex, which triggers a signaling cascade that eventually activates the steroidogenic acute regulatory (StAR) protein to allow for cholesterol uptake into the mitochondria.  Cholesterol then undergoes a series of reactions during steroidogenesis, which is a process that ultimately leads to the synthesis of aldosterone from cholesterol. Aldosterone then goes to act on the distal convoluted tubule and the collecting duct to make them more permeable to sodium to allow for its reuptake.  Water subsequently follows sodium back into the system, which would therefore increase the circulating blood volume.  In addition, potassium and hydrogen are also being excreted into the urine simultaneously to maintain the electrolyte balance.  "
What is the definition of Striated Muscle Contraction?,"Tubular striated muscle cells (i.e. skeletal and cardiac myocytes) are composed of bundles of rod-like myofibrils. Each individual myofibril consists of many repeating units called sarcomeres. These functional units, in turn, are composed of many alternating actin and mysoin protein filaments that produce muscle contraction.  The muscle contraction process is initiated when the muscle cell is depolarized enough for an action potential to occur. When acetylcholine is released from the motor neuron axon terminals that are adjacent to the muscle cells, it binds to receptors on the sarcolemma (muscle cell membrane), causing nicotinic acetylcholine receptors to be activated and the sodium/potassium channels to be opened. The fast influx of sodium and slow efflux of potassium through the channel causes depolarization.  The resulting action potential that is generated travels along the sarcolemma and down the T-tubule, activating the L-type voltage-dependent calcium channels on the sarcolemma and ryanodine receptors on the sarcoplasmic reticulum. When these are activated, it triggers the release of calcium ions from the sarcoplasmic reticulum into the cytosol. From there, the calcium ions bind to the protein troponin which displaces the tropomysoin filaments from the binding sites on the actin filaments.  This allows for myosin filaments to be able to bind to the actin.  According to the Sliding Filament Theory, the myosin heads that have an ADP and phosphate attached binds to the actin, forming a cross-bridge.  Once attached, the myosin performs a powerstroke which slides the actin filaments together.  The ATP and phosphate are dislodged during this process.  However, ATP now binds to the myosin head, which causes the myosin to detach from the actin.  The cycle repeats once the attached ATP dissociates into ADP and phosphate, and the myosin performs another powerstroke, bringing the actin filaments even closer together.  Numerous actin filaments being pulled together simultaneously across many muscles cells triggers muscle contraction."
What is the definition of Gastric Acid Production?,"Gastric acid plays a key role in the digestion of proteins by activating digestive enzymes to break down long chains of amino acids. In addition, it aids in the absorption of certain vitamins and minerals and also acts as one of the body's first line of defence by killing ingested micro-organisms.  This digestive fluid is formed in the stomach (specifically by the parietal cells) and is mainly composed of hydrochloric acid (HCl).  However, it is also constituted of potassium chloride (KCl) and sodium chloride (NaCl). The main stimulants of acid secretion are histamine, gastrin, and acetylcholine which all, after binding to their respective receptors on the parietal cell membrane, trigger a G-protein signalling cascade that causes the activation of the H+/K+ ATPase proton pump. As a result, hydrogen ions are able to be pumped out of the parietal cell and into the lumen of the stomach.  The hydrogen ions are available inside the parietal cell after water and carbon dioxide combine to form carbonic acid(the reaction is catalyzed by the carbonic anhydrase enzyme) which dissociates into a bicarbonate ion and a hydrogen ion.  Moreover, the chloride and potassium ions are transported into the stomach lumen through their own channels so that hydrogen ions and/or potassium ions can form an ionic bond with chloride ions to form HCl and/or KCl, which are both constituents of stomach acid.  In addition, the peptide hormone somatostatin is the main inhibitor to gastric acid secretion.  Not only does it inhibit the G-protein signalling cascade that leads to proton pump activation, but it also directly acts on the enterochromaffin-like cells and G cells to inhibit histamine and gastrin release, respectively."
What is the definition of Felbamate Metabolism Pathway?,"Felbamate is metabolized in the liver. One route of metabolism consists of the hydroxylation to 2-hydroxyfelbamate or p-hydroxyfelbamate, which is catalyzed by CYP2E1 and CYP3A4. Moreover, felbamate can be transformed to 2-phenyl-2-propanediol monocarbamate. This metabolite is then converted to 3-carbamoyl-2phenylpropionaldehyde via alchol dehydrogenase 1A, which in turn can be transformed into three possible metabolites: atropaldehyde, 3-carbamoyl-2-phenylpropionic acid (catalyzed by the dimeric NADP-preferring aldehyde dehydrogenase), and 4-hydroxy-5-phenyltetrahydro-1,3-oxazin-2-one. The latter is further converted by the alcohol dehydrogenase 1A to 5-phenyl-1,3-oxazinane-2,4-dione, which is subsequently transformed to 3-carbamoyl-2-phenylpropionic acid."
What is the definition of Carbamazepine Metabolism Pathway?,"Carbamazepine is a drug used in the treatment of epilepsy, bipolar disorder, trigeminal neuralgia, and other psychiatric disorders. Carbamazepine is almost entirely metabolized in the liver, with the primary metabolic pathway being conversion to 10,11-epoxycarbamazepine. Ring hydroxylation to 2-hydroxycarbamazepine and 3-hydroxycarbamazepine represent a minor metabolic route, presumably though a carbamazepine 2,3-epoxide intermediate. Potential bioactivation occurs via CYP3A4-mediated secondary oxidation of 2-hydroxycarbamazepine to the potentially reactive carbamazepine iminoquinone and of 3-hydroxycarbamazepine to form other reactive metabolites. Radicals can also be formed from metabolism of 3-hydroxycarbamazepine by myeloperoxidase. Oxcarbazepine, an anticonvulsant used primarily in the treatment of epilepsy, is converted to 10,11-dihydroxycarbamazepine via 10-hydroxycarbazepine."
What is the definition of Valproic Acid Metabolism Pathway?,"Valproic acid (VPA) is metabolized almost entirely in the liver, via at least there routes: glucuronidation, beta oxidation in the mitochondria, and cytochrome P450 mediated oxidation. The glucuronidation of VPA is mediated by UGT1A3, UGT1A4, UGT1A6, UGT1A8, UGT1A9, UGT1A10, UGT2B7 and UGT2B15. The key CYP-mediated reaction of the VPA metabolic pathway is the generation of 4-ene-VPA by CYP2C9, CYP2A6 and CYP2B6. These three enzymes also catalyze the formation of 4-OH-VPA and 5-OH-VPA. Moreover, CYP2A6 mediates the oxidation of VPA to 3-OH-VPA. Inside the mitochondria, the first step of oxidation is the formation of (VPA-CoA) catalyzed by medium-chain acyl-CoA synthase, followed by the conversion to 2-ene-VPA-CoA through 2-methyl-branched chain acyl-CoA dehydrogenase (ACADSB). 2-ene-VPA-CoA is further converted to 3-hydroxyl-valproyl-VPA (3-OH-VPA-CoA) by an enoyl-CoA hydratase, crotonase (ECSH1) and then 3-OH-VPA-CoA is metabolized to 3-keto-valproyl-CoA (3-oxo-VPA-CoA) through the action of 2-methyl-3-hydroxybutyryl-CoA dehydrogenase. Another route of VPA metabolism in the mitochondria includes the conversion of 4-ene-VPA to 4-ene-VPA-CoA ester catalyzed by ACADSB, followed by a beta-oxidation to form 2,4-diene-VPA-CoA ester. The latter metabolite can furthermore be conjugated to glutathione to form thiol metabolites."
What is the definition of Venlafaxine Metabolism Pathway?,"Venlafaxine (also named as Effexor or Elafax) is an antidepressant medication, which belongs to the class of serotonin-norepinephrine reuptake inhibitor (SNRI). Venlafaxine is well absorbed into the circulation system. Venlafaxine is also metabolized to N-desmethylvenlafaxine. The N-demethylation is catalyzed by CYP3A4 and CYP2C19. N-desmethylvenlafaxine is a weaker serotonin and norepinephrine reuptake inhibitor. Both O-desmethylvenlafaxine (as potent a serotonin-norepinephrine reuptake inhibitor) and N-desmethylvenlafaxine are further metabolized by CYP2C19, CYP2D6 and/or CYP3A4 to a minor metabolite N,O-didesmethylvenlafaxine that is further metabolized into N,N,O-tridesmethylvenlafaxine or excreted as N,O-didesmethylvenlafaxine gucuronide. Later on, O-desmethylvenlafaxine is exported without any change in chemical structure. Venlafaxine is exported via two transporters: Multidrug resistance protein 1 and ATP-binding cassette sub-family G member 2. "
What is the definition of Tramadol Metabolism Pathway?,"Tramadol (also named Ultram) is a class of opioid pain medication that used for treating pain. Metabolism of tramadol mainly happened in liver cell. The N-demethylation of tramadol is catalyzed by the cytochrome CYP3A4 and CYP2B6 to form N-Desmethyltramadol, which further metabolized to N,N-Didesmethyltramadol through CYP3A4 and CYP2B6 and to N,O-Didesmethyltramadol through CYP2D6. The O-demethylation of tramadol is catalyzed by the cytochrome CYP2D6 to form O-Desmethyltramadol, which further metabolized to O-Desmethyltramadol glucuronide through UDP-glucuronosyltransferase 2B7 and UDP-glucuronosyltransferase 1-8. O-Desmethyltramadol can also be metabolized to N,O-Didesmethyltramadol through CYP2D6."
What is the definition of Levomethadyl Acetate Metabolism Pathway?,"Levomethadyl Acetate (also known as levacetylmethadol or levo-α-acetylmethadol) (LAAM), is a synthetic opioid structurally similar to methadone. It is an opioid agonist that has been used as an analgesic and to treat opioid dependence. Levomethadyl Acetate is metabolized by cytochrome P450 3A4 in two N-demethylation reactions to nor-levomethadyl acetate (nor-LAAM) and subsequently to dinor-levomethadyl acetate (dinor-LAAM)."
What is the definition of Clomipramine Metabolism Pathway?,"Clomipramine is a dibenzazepine-derivative tricyclic antidepressant. Clomipramine may be used to treat obsessive-compulsive disorder and disorders with an obsessive-compulsive component (e.g. depression, schizophrenia, Tourette's disorder)."
What is the definition of Acetaminophen Metabolism Pathway?,"Acetaminophen (APAP) is metabolized primarily in the liver. Glucuronidation is the main route, accounting for 45-55% of APAP metabolism, and is mediatied by UGT1A1, UGT1A6, UGT1A9, UGT2B15 in the liver and UGT1A10 in the gut. APAP can also by metabolized via sulfation, accounting for 30-35% of the metabolism. In the liver, this step is catalyzed by the sulfotransferases SULT1A1, SULT1A3, SULT1A4, SULT1E1 and SULT2A1. Moreover, APAP can also be activated to form the toxic N-acetyl-p-benzoquinone imine (NAPQI) under the mediation of CYP3A4, CYP2E1, CYP2D6 CYP1A2, CYP2E1 and CYP2A6."
What is the definition of Doxepin Metabolism Pathway?,"Doxepin is a tricyclic antidepressant (TCA) that can be used for treating major depressive disorder, sleep maintenance. Doxepin is metabolized by cytochrome P450 2C19, 1A2, 2C9, 3A4 to form N-desmethyldoxepin, and form (E)-2-hydroxydoxepin by solely cytochrome P450 2D6 in ER of liver."
What is the definition of Nevirapine Metabolism Pathway?,"Nevirapine is used in the treatment of human immunodeficiency virus (HIV) type 1 (HIV-1) infection. It is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that binds to the tyrosines at amino acid residues 181 and 188 of HIV-1 reverse transcriptase. Nevirapine is metabolized in the liver to 2-, 3-, 8-, and 12-hydroxynevirapine by the induction of CYP enzymes, mainly CYP3A4 and CYP2B6. 12-hydroxynevirapine may be further oxidated by ALDH to form 4-carboxynevirapine. These hydroxyl metabolites are glucuronidated by UDP glucuronosyl transferases (UGTs), then exit the cell via the adenosine triphosphate-binding cassette gene ABCC10 for urinary excretion."
What is the definition of Sorafenib Metabolism Pathway?,"Sorafenib is a drug that belongs to the antineoplastics drug class, which is the drug class relating to the treatment of cancer, specifically renal, hepatic and thyroid cancers. This drug works by stopping cancerous tumour progress and stopping therapy replication pf potentially malignant cells. It does this by inhibiting protein synthesis, as we will explore in the pathway. Sorafenib is administered orally, in a tablet form taken twice daily without food. Once ingested, sorafenib finds itself in the endoplasmic reticulum membrane , where it inhibits cytochrome P450 2B6, cytochrome P450 2C8, cytochrome P450 2C9 and UDP-glucuronosyltransferase 1-1. Sorafenib is also catalyzed, with the help uridine diphosphate glucuronic acid and the enzyme UDP-glucuronosyltransferase 1-9 to sorafenib b-D-glucuronide with a by-product of uridine 5’-diphosphate. Sorafenib also undergoes a transformation without the use of catalytic enzymes and becomes sorafenib metabolite M4 and subsequently becomes sorafenib metabolite M5. In another reaction, sorafenib teams up with water and oxygen, using cytochrome P450 3A4 to create sorafenib N-oxide and hydrogen peroxide. Sorafenib N-oxide then undergoes two more reactions, one where it becomes sorafenib N-oxide glucuronide, and another where it becomes sorafenib metabolite M1. Sorafenib metabolite M1 is also attached to another reaction, as sorafenib creates sorafenib metabolite M3, sorafenib metabolite M1 is also created from this metabolite. "
What is the definition of Lamivudine Metabolism Pathway?,"Lamivudine (2'-deoxy-3'-thiacytidine, 3TC) is a pyrimidine analog reverse transcriptase enzyme inhibitor used to treat human immunodeficiency virus type I (HIV-1), HIV-2, and Hepatitis B. When metabolized to its active triphosphate form, it competes with deoxycytidine triphosphate for binding to reverse transcriptase, resulting in chain termination when incorporated into the viral DNA. Lamivudine may enter the cells by passive diffusion or by active transported via SLC22A1, SLC22A2, and SLC22A3. Intracellularly, it is phosphorylated to its active triphosphate from via deoxycytidine kinase (3TC to 3TC-monophosphate), followed by cytidine monophosphate/deoxycytidine monophosphate kinase (3TC-monophosphate to 3TC-diphosphate), then 3'-phosphoglycerate kinase or nucleoside diphosphate kinase (3TC-diphosphate to 3TC-triphosphate). Dephosphorylation can occur via phosphatases or salvage pathways. Lamivudine is actively transported out of cell by efflux transporters ABCB1, ABCC1, ABCC2, ABCC3, ABCC4 and ABCG2 and primarily excreted unchanged in the urine."
What is the definition of Doxorubicin Metabolism Pathway?,"Doxorubicin is an anthracycline antibiotic used as a cancer chemotherapy drug. The major metabolic route of doxorubicin metabolism is two-electron reduction to doxorubicinol. A second route is one-electron reduction resulting in a doxorubicin-semiquinone, which can be undertaken by NADH dehydrogenases in the sarcoplasmic reticulum or mitochondrion, or nitric oxide synthases, NADPH dehydrogenase, or xanthine oxidase. Reactive oxygen species are formed when the semiquinone is re-oxidized back to doxorubicin. The reactive oxygen species are thought by some to be responsible for the drug's effects and cardiotoxicity, and can be deactivated by glutathione peroxidase, catalase, and superoxide dismutase. A third and minor metabolic route involves deglycosidation and results in the formation of doxirubicinol hydroxyaglycone. Approximately 50% of doxorubicin is eliminated unchanged from the body."
What is the definition of Artemether Metabolism Pathway?,"Artemether is a semisynthetic derivative of artemisinin, a phytoconstituent that acts as a short-acting antimalarial agent and is used to treat uncomplicated Plasmodium falciparum malaria. Artemisinin derivatives kill parasites more rapidly than conventional antimalarial drugs, and are active against both the sexual and asexual stages of the parasite cycle. However due to their short half-life (and to prevent resistance development) artemisinin compounds are often combined with long-acting antimalarial drugs. Artemeter is administered orally and as an oil-based intramuscular injection. The antimalarial activity of artemether and other artemisinin derivatives is a result of the peroxide bridge found in the active metabolite dihydroartemisinin. Dihydroartemisinin is formed from the rapid demethylation of artmether via CYP3A4 and CYP3A5. It then undergoes glucuronidation catalyzed by the UDP-glucuronosyltransferases UGT1A9 and UGT2B7 into inactive metabolites that are eliminated in the bile."
What is the definition of Mycophenolic Acid Metabolism Pathway?,"Mycophenolic Acid (MPA) is an immunosuppressive agent that acts as a noncompetitive, selective and reversible inhibitor of inosine monophosphate dehydrogenase (IMPDH). It is available as a prodrug, Mycophenolate mofetil (MMF), which is a 2-morpholinoethyl ester with improved bioavailability. After absorption, MMF is hydrolyzed to MPA and N-(2-carboxymethyl)- morpholine, N-(2-hydroxyethyl)-morpholine, and the N-oxide of N-(2-hydroxyethyl)-morpholine by the carboxylesterases CES-1 (in the liver only) and CES-2 (in the liver and intestine). The morpholine metabolites are excreted in the urine. MPA is glucuronidated by UDP glucuronosyl transferases (UGTs) UGT1A7, UGT1A8, UGT1A9 and UGT1A10 to MPA-7-O-glucuronide, which is excreted in the urine. Other metabolites of MPA include MPA-acyl glucoronide, which is formed by UGT2B7, and 6-O-desmethyl-MPA, which is formed by the CYP enzymes CYP3A4, CYP3A5 and CYP2C8. MPA enters hepatocytes by the organic anion transport proteins (OATPs) SLCO1B1 and SLCO1B3. MPA and its metabolites are excreted in the bile via the ABCC2, ABCG2, and ABCB1 proteins."
What is the definition of Rosiglitazone Metabolism Pathway?,"Rosiglitazone is an anti-diabetic drug in the thiazolidinedione class of drugs. It is extensively metabolized in the liver by the cytochrome p450 enzymes CYP2C8 and CYP2C9 to para-hydroxy rosiglitazon, ortho-hydroxy rosiglitazone and N-desmethyl rosiglitazone. N-desmethyl rosiglitazone is the major metabolite and is further metabolized to N-desmethyl-p-hydroxyrosiglitazone, N-desmethyl glucuronide rosiglitazone and N-desmethyl-O-hydroxy rosiglitazone. Both para-hydroxy rosiglitazon and ortho-hydroxy rosiglitazone are excreted as sulfated or glucuronidated metabolites."
What is the definition of Warburg Effect?,"The Warburg Effect refers to the phenomenon that occurs in most cancer cells where instead of generating energy with a low rate of glycolysis followed by oxidizing pyruvate via the Krebs cycle in the mitochondria, the pyruvate from a high rate of glycolysis undergoes lactic acid fermentation in the cytosol. As the Krebs cycle is an aerobic process, in normal cells lactate production is reserved for anaerobic conditions. However, cancer cells preferentially utilize glucose for lactate production via this “aerobic glycolysis”, even when oxygen is plentiful. The Warburg Effect is thought to be the result of mutations to oncogenes and tumour suppressor genes. It may be an adaptation to low-oxygen environments within tumors, the result of cancer genes shutting down the mitochondria, or a mechanism to aid cell proliferation via increased glycolysis. The Warburg Effect involves numerous pathways, including growth factor stimulation, transcriptional activation, and glycolysis promotion."
What is the definition of Phenindione Action Pathway?,"Phenindione (also known as Dindevan and Fenilin) is an anticoagulant that inhibit the liver enzyme vitamin K reductase, which cause Vitamin K1 2,3-epoxide could not be catalyzed by vitamin K reductase to form vitamin KH2, the reduced form of vitamin K. Vitamin K-dependent coagulation factors (II, VII, IX, and X) requires its cofactor, vitamin K to facilitate the activation and gamma-carboxylation. Inhibition of vitamin K reductase results in reduced concentration of vitamin KH2, which will ultimately lead to decreased coagulability of the blood and reduced cleavage of fibrinogen into fibrin."
What is the definition of Dicoumarol Action Pathway?,"Dicoumarol (also known as bishydroxycoumarin) is an anticoagulant that inhibit the liver enzyme vitamin K reductase, which cause Vitamin K1 2,3-epoxide could not be catalyzed by vitamin K reductase to form vitamin KH2, the reduced form of vitamin K. Vitamin K-dependent coagulation factors (II, VII, IX, and X) requires its cofactor, vitamin K to facilitate the activation and gamma-carboxylation. Inhibition of vitamin K reductase results in reduced concentration of vitamin KH2, which will ultimately lead to decreased coagulability of the blood and reduced cleavage of fibrinogen into fibrin."
What is the definition of Bopindolol Action Pathway?,"Bopindolol (also known as Sandonorm) is a selective β1 adrenergic receptor antagonist (beta blocker), which can be used for treatment of high blood pressure (hypertension) and irregular heartbeats (arrhythmias). Bopindolol also has the ability to mild intrinsic sympathomimetic activity (ISA) with effective range of dosage. Adrenaline (also known as epinephrine) can activate β1 adrenergic receptor so that the heart rate and output will be increased. Renin is a hormone that generated from kidney, which could lead to constriction of blood vessels. Beta blockers could efficiently prohibit renin release.  "
What is the definition of Carteolol Action Pathway?,"Carteolol (also known as Cartrol or Ocupress) is a selective β1 adrenergic receptor antagonist (beta blocker), which can be used for treatment of high blood pressure (hypertension) and irregular heartbeats (arrhythmias). Carteolol also has the ability to mild intrinsic sympathomimetic activity (ISA) with effective range of dosage. Adrenaline (also known as epinephrine) can activate β1 adrenergic receptor so that the heart rate and output will be increased. Renin is a hormone that generated from kidney, which could lead to constriction of blood vessels. Beta blockers could efficiently prohibit renin release.  "
What is the definition of Timolol Action Pathway?,"Timolol is a beta blocker medication, making it part of the antihypertensive drug class. It relieves symptoms such as tachycardia, vascular headaches, hypertension, angina and tremors. Timolol, much like propranolol or oxprenolol, begins its journey by inhibiting the beta-1 adrenergic receptors in the heart. Entering the myocyte, this activates a G-protein signalling cascade, which activates cAMP -dependent protein kinase type 1-alpha regulatory subunit. From there, cAMP-dependent protein kinase catalytic subunit alpha activates outage-dependent L-type calcium channel subunit alpha 1C and 2 other transports which bring calcium into the myocyte from outside of the cell. cAMP-dependent protein kinase catalytic subunit alpha is activated through ryanodine receptor 2, which is also transporting calcium into the myocyte from the the sarcoplasmic reticulum. The calcium and calmodulin then activate myosin light chain kinase, which is located in the smooth vascular muscle. This, paired with the calcium activating a series of troponin enzymes that activate tropomyosin enzymes in the striated muscle, results in a muscle contraction. Then in the cell membrane we have PIP2(16:0/20:3(8Z,11Z,14Z)) catalyzing into DG(14:0/14:1(9Z)/0:0) and inositol 1,4,5-triphosphate with the help of the enzyme 1-phosphatidylinositol 4,5-biphosphate phosphodiesterase beta-1. This enzyme is activated through the G-protein signalling cascade, which stems from the type-1 angiotensin II receptor. Around the cell there are many transports happening through many different transporters, leading in and out of the cell Some of the transports into the cell include sodium and calcium, while transports are also working hard to constantly export potassium from the cell. Returning to the sarcoplasmic reticulum, cardiac phospholamban inhibits the transporter sarcoplasmic/endoplasmic reticulum calcium ATPase 2, which sees water and ATP catalyzed through it to become phosphorus and ADP, while transporting calcium into the sarcoplasmic reticulum."
What is the definition of Sotalol Action Pathway?,"Sotalol is a beta-adrenergic receptor antagonist, which is a treatment regimen for heart failure such as abnormal heart rhythms. Sotalol inhibits response to adrenergic stimuli by competitively blocking β1-adrenergic receptors within the myocardium and β2-adrenergic receptors within bronchial and vascular smooth muscle. The electrophysiologic effects of sotalol may be due to its selective inhibition of the rapidly activating component of the potassium channel involved in the repolarization of cardiac cells."
What is the definition of Epinephrine Action Pathway?,"Epinephrine can be derived from phenylalanine and tyrosine and it is an active sympathomimetic hormone that can be secreted from adrenal medulla. Epinephrine can stimulate alpha-  and beta- adrenergic systems by binding on alpha-1 and beta-1 adrenergic receptors to make gastrointestinal relaxation, stimulates the heart, etc. Epinephrine can also be used to delay absorption of local anesthetics, constrict arterioles in skin and gut while dilating arterioles in leg muscles, increase glycogen hydrolysis to glucose in liver to raise up blood sugar level and breaking down lipids in adipocytes. Epinephrine can also play role as suppressive agent in immune system."
What is the definition of Dobutamine Action Pathway?,"Dobutamine is a type of medication that can be used for treating heart failure and cardiogenic shock. Dobutamine can bind to beta-1 adrenergic receptor on the heart cell which lead to mild chronotropic, arrhythmogenic, hypertensive and vasodilative effects. Dobutamine can also bind to beta-2 or alpha receptors. For patients with cardiac decompensation, dobutamine is required for inotropic support. "
What is the definition of Isoprenaline Action Pathway?,"Isoprenaline (also known as isoproterenol) is a selective beta adrenergic bronchodilator that can be used for treating slow heart rate (bradycardia), heart block, and rarely for asthma. Isoprenaline can bind and inhibit beta-1 adrenergic receptor on both vascular smooth muscle, which lead to inhibition of vasoconstriction in peripheral blood vessels and adrenergic stimulation of endothelial cell function. "
What is the definition of Arbutamine Action Pathway?,"Arbutamine is a synthetic catecholamine used to initiate a cardiac stress response to mimic exercise to detect coronary artery disease. Arbutamine has nonselective beta and weak alpha-1-adrenergic activity which causes increased chronotropic activity (increase in heart rate) and inotropic activity (increase myocardial contractility). These effects mimic the cardiovascular effects of exercise. For patients with cardiovascular artery disease, arbutamine can induce myocardial ischemia. Arbutamine is delivered via a computer controlled closed-loop system. The infusion of arbutamine is based off the heart rate feedback. The system monitors heart rate and blood pressure throughout infusion with alarms for physiological changes or problems. "
What is the definition of Amiodarone Action Pathway?,"Amiodarone, trade name Cordarone and Nexterone, is an antianginal and a class III antiarrhythmic drug prescribed to treat irregular heart rhythms. The drug inhibits Na,K-activated myocardial adenosine triphosphatase, calcium and potassium channels and beta adrenergic receptors causing an increase in ventricular and atrial muscle action duration. This inhibition causes prevents repolarization of the cells causing heart rate to decrease and vascular resistance to decrease. Amiodarone exerts its antiarrhythmic effect by prolonging the duration of myocardial cell-action potentials. Amiodarone is unique to other class III antiarrhythmic drugs due to its effect on beta adrenergic receptors, calcium channels and sodium channels. "
What is the definition of Levobunolol Action Pathway?,"Levobunolol (also known as Betagan) is an ophthalmic beta blocker (non-selective) that can produce cardiovascular effects and systemic pulmonary effects. Levobunolol bind to beta1-adrenergic and beta2-adrenergic receptors in heart and vascular smooth muscle to block the binding of other adrenergic neurotransmitters such as norepinephrine, which lead to decreased blood pressure, heart rate and cardiac output. "
What is the definition of Metipranolol Action Pathway?,"Metipranolol (also known as Betanol or Disorat) is an  beta blocker (non-selective) that can used as an antihypertensive, antiarrhythmic and antiglaucoma agent. Metipranolol binds to beta1-adrenergic and beta2-adrenergic receptors in heart and vascular smooth muscle. Metipranolol demonstrates low intrinsic sympathomimetic activity, and weak local anesthetic (membrane-stabilizing) and myocardial depressant activity. Metipranolol can also reduce the producion of aqueous humor."
What is the definition of Bevantolol Action Pathway?,"Bevantolol hydrocholride, also known as bevantolol, is a cardioselective beta blocker prescribed to treat angina pectoris and hypertension. Bevantolol is an antagonist of beta-1 adrenoreceptors to block the G protein signalling cascade and inhibit epinephrine induced sympathetic activation such as, increased heart rate. It does not have intrinsic sympathomimetic activity therefore does not stimulate beta-adrenergic receptors. This results in a decrease in preload and blood pressure. "
What is the definition of Practolol Action Pathway?,"Practolol (also known as Eraldin or Dalzic) is a beta blocker (non-selective) that are used for treat high blood pressure or chest pain. Practolol bind to beta1-adrenergic receptors in heart and vascular smooth muscle to block the binding of other adrenergic neurotransmitters such as norepinephrine, which lead to decreased blood pressure, heart rate and cardiac output. Practolol can also bind beta-2 adrenergic receptors in juxtaglomerular apparatus and bronchiole smooth muscle. In juxtaglomerular apparatus, practolol can prevent the production of aldosterone and angiotensin II by inhibiting renin production, which lead to prevention of water retention and vasoconstriction. In bronchiole smooth muscle, binding of practolol to beta-2 adrenergic receptors can also prevent vasoconstriction. "
What is the definition of Bupranolol Action Pathway?,"Bupranolol is a nonselective beta-blocker with structural similarity to propanolol. Both drugs do not have intrinsic sympathomimetic activity. It competes with catecholamines for binding beta-1 adrenergic receptors in the heart to inhibit sympathetic activation. This inhibition causes decreased heart rate, cardiac output, blood pressure "
What is the definition of Tramadol Action Action Pathway?,"Tramadol is an analgesic drug consisting of two enantiomer forms (+)-Tramadol and (-)-Tramadol. Both contribute to pain relief by inhibiting pain transmission in the spinal cord via different mechanisms. (+)-Tramadol is a selective agonist of the mu receptor (OP3) inhibiting serotonin reuptake, while (-)-Tramadol inhibits norepinephrine reuptake in the central nervous system. Although tramadol is structurally related to codeine and morphine, it’s affinity for the mu receptor compared to other opioids is significantly less. Therefore tramadol is used when treatment with strong opioids is not necessary since it’s pharmacodynamic and pharmacokinetic properties suggest the low likelihood of patients becoming dependent."
What is the definition of Propoxyphene Action Pathway?,"Propoxyphene is an analgesic in the opioid category. It primarily acts on the G protein coupled receptors, OP3. Propoxyphene binding to OP3 causes GTP exchange for GDP and inhibit adenylate cyclase causing decreased intracellular cAMP. This leads to the inhibition of nociceptive neurotransmitters such as: substance P, GABA, dopamine, acetylcholine and noradrenaline. Opioids inhibit vasopressin, somatostatin, insulin and glucagon release. Propoxyphene also causes the closure of voltage-gated calcium channels and opens potassium channels causing the hyperpolarization of the membrane and decreasing neuronal excitability. This further reduces the feeling of pain. "
What is the definition of Levorphanol Action Pathway?,"Levorphanol (also known as  Levo-Dromoran) is an opioid medication that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of levorphanol will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Therefore, levorphanol can reduce nerve conduction and decrease neurotransmitter release; so that perception of pain signals can be blocked."
What is the definition of Anileridine Action Pathway?,"Anileridine (also known as Leritine) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of anileridine will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Diphenoxylate Action Pathway?,"Diphenoxylate (also known as Difenossilato or Lomotil) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of diphenoxylate will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Dezocine Action Pathway?,"Dezocine (also known as Dalgan) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of dezocine will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Levomethadyl Acetate Action Action Pathway?,"Levomethadyl acetate (also known as LAAM) is a synthetic synthetic opioid analgesic with multiple actions quantitatively similar to those as morphine, the most prominent of which involve the central nervous system and organs composed of smooth muscle. However, levomethadyl acetate is more active and more toxic than morphine. Levomethadyl acetate can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of levomethadyl acetate will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Therefore, methadyl acetate can reduce nerve conduction and decrease neurotransmitter release; so that perception of pain signals can be blocked. Levomethadyl acetate can also open calcium-dependent inwardly rectifying potassium channels (OP1 receptor agonist) to reduce neuronal excitability as well as lead to hyperpolarization."
What is the definition of Methadyl Acetate Action Pathway?,"Methadyl Acetate (also known as Acetylmethadol) is a synthetic opioid analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of methadyl acetate will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Therefore, methadyl acetate can reduce nerve conduction and decrease neurotransmitter release; so that perception of pain signals can be blocked."
What is the definition of 3-Methylthiofentanyl Action Pathway?,"Methadyl Acetate  (also known as Acetylmethadol) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of methadyl acetate  will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Dimethylthiambutene Action Pathway?,"Dimethylthiambutene (also known as Ohton or Aminobutene) is an opioid analgesic and substrate for mu-type opioid receptor which can be used for relieving  pain. Dimethylthiambutene can act on mu-opiod receptor on neurons located at central nervous system. Binding of dimethylthiambutene on mu-type opioid receptor can activate associated G(i) proteins, which inhibits adenylate cyclase and reduce intracellular cAMP level. G(i) protein can also open potassium channels and close calcium channels to result in hyperpolarize on neuron. Binding of dimethylthiambutene on mu-type opioid receptor will eventually relieving the pain by reducing nerve conduction and neurotransmitter release."
What is the definition of Ethylmorphine Action Pathway?,"Ethylmorphine (also known as codethyline and dionine) is an opioid analgesic. Ethylmorphine can be metabolized to form morphine by cytochrome P450 2D6 (CYP2D6). Morphine can bind the mu-type opioid receptor on central nervous system (CNS) to reduce the pain. Morphine can also bind and inhibit gamma-Aminobutyric acid (GABA) inhibitory interneurons. These interneurons can inhibit the descending pain inhibition pathway; therefore, without the interneurons, pain modulation will go downstream. "
What is the definition of Leucine Stimulation on Insulin Signaling?,"The branched chain amino acid (BCAA) leucine is able to signal transduction pathways that modulate translation initiation for protein synthesis in skeleton muscles. In the presence of leucine, hyperphosphorylation of 4E-BP1 causes its affinity for eIF4E to be lowered. This allows eIF4F protein complexes to recognize, unfold and guide the mRNA to the 43S preinitiation complex thereby increasing translation initiation. In addition, leucine has a transient affect on the release of insulin and/or enhances sensitivity of muscle cells to insulin. A culmination of both signals at the mammalian target of rapamycin (mTOR) and perhaps other signaling, such as PKCδ, are needed for maximum translation initiation to occur. "
What is the definition of Levallorphan Action Pathway?,"Levallorphan (also known as Lorfan and Naloxifan) is a type of medication that can be used for treating drug overdoses and respirotry depression. Levallorphan can bind to mu-type opioid receptor and kappa-type opioid receptor on neuron of central nerves system (CNS). Effects of opioids such as respiratory depression, hypotension and sedation can be prevented or reversed by levallorphan. Levallorphan can also be used for treating pentazocine which is a type of psychotomimetic and dysphoric effects of agonist-antagonists."
What is the definition of Buprenorphine Action Pathway?,"Buprenorphine, trade name subutex, suboxone, zubsolv and bunavail, is a partial agonist of mu-opioid receptors and a kappa-opioid receptor antagonist and is prescribed for opioid addiction to prevent cravings and symptoms of withdrawal. The binding of these receptors causes hyperpolarization and decreased neuronal excitability. Buprenorphine has a longer duration of action due to its slow dissociation from the receptor. This long rate of action causes a long clinical effect and decreases physical dependence. Buprenorphine can also prevent opioid use by inhibiting exogenous opioid effects. This elimination of the rush from the opioid can block the reinforcing behaviour of the drug and may treat opioid addiction. Buprenorphine is available on its own or in combination with naloxone. "
What is the definition of Alvimopan Action Pathway?,"Alvimopan is prescribed to treat patient opioid-induced constipation, a common side effect of opioid therapy. This side effect results in delayed discharge for hospitalized patients following surgery. Alvimopan helps to increase gastrointestinal recovery following surgery for a shorter hospital stay. Opioids bind opioid receptors in the gut causing inhibition of gut motility which results in constipation. Alvimopan is a peripherally acting mu-opioid antagonist. The drug acts in the gastrointestinal tract by competing to bind the mu-opioid receptor. Alvimopan differs from other peripherally acting mu-receptor antagonists such as, methylnaltrexone, by the presence of a quaternary amine.  "
What is the definition of Pentazocine Action Pathway?,"Pentazocine (also known as Talwin) is a type of medication that can relieve moderate to severe pain. Pentazocine can bind to mu-type opioid receptor and kappa-type opioid receptor on neuron of central nerves system (CNS). Binding of pentazocine on mu-type opioid receptor and kappa-type opioid receptor can lead to decreased level of neuronal excitability and hyperpolarization. After binding to the receptor, pentazocine will slowly dissociate. "
What is the definition of Naltrexone Action Pathway?,"Naltrexone (also known as ReVia and Vivitrol) is a competitive antagonist of mu-type opioid receptor in the central nervous system (CNS). Naltrexone is also a type of medication that are used for manage opioid or alcohol dependence. Binding of naltrexone can prevent the effects that caused by endogenous opioids, which results in antagonization of effects of opiates such as respiratory depression or drug craving."
What is the definition of Naloxone Action Pathway?,"Naloxone (also known as Narcan) is a competitive antagonist of mu-type opioid receptor in the central nervous system (CNS). Naloxone is also a type of medication that are used for manage opioid or alcohol dependence. Binding of naloxone can prevent the effects that caused by endogenous opioids, which results in antagonization of effects of opiates such as respiratory depression or drug craving. In recent study, naloxone shows that it can also bind to kappa and gamma-opioid receptors."
What is the definition of Dihydromorphine Action Pathway?,"Dihydromorphine (also known as Paramorfan or Paramorphan) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of dihydromorphine acetate  will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Ketobemidone  Action Pathway?,"Ketobemidone (also known as Ketogan) is analgesic that can bind to mu-type opioid receptor to activate associated G-protein in the sensory neurons of central nervous system (CNS), which will reduce the level of intracellular cAMP by inhibiting adenylate cyclase. The binding of ketobemidone acetate  will eventually lead to reduced pain because of decreased nerve conduction and release of neurotransmitter. Hyperpolarization of neuron is caused by inactivation of calcium channels and activation of potassium channels via facilitated by G-protein. "
What is the definition of Nalbuphine Action Pathway?,"Nalbuphine (also known as Rubuphine and Nubain) is a competitive antagonist of mu-type and kappa-type opioid receptor in the central nervous system (CNS). Nalbuphine is also a type of medication that are mainly used for treat pain. Binding of nalbuphine can prevent the effects that caused by endogenous opioids, which results in antagonization of effects of opiates such as respiratory depression or drug craving. "
What is the definition of Antipyrine Action Pathway?,"Antipyrine (also named Fenazone or Phenazone) is often used for testing the effect of other drugs on drug-metabolizing enzymes in the liver. Antipyrine can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of antipyrine. "
What is the definition of Antrafenine Action Pathway?,"Antrafenine (also named Stakane) acts as an anti-inflammatory and analgesic drug. It is not widely used as it has largely been replaced by newer drugs. Antrafenine can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of antrafenine. "
What is the definition of Carprofen Action Pathway?,"Carprofen (also named Rimadyl or Imadyl) is a nonsteroidal anti-inflammatory drug that can treat various joint pain or post-operative pain. Carprofen can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of Carprofen. "
What is the definition of Etoricoxib Action Pathway?,"Etoricoxib (also named as Arcoxia) is a COX-2 selective inhibitor. It can be used to treat fever, pain, swelling, inflammation, and platelet aggregation. Etoricoxib can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. "
What is the definition of Fenoprofen Action Pathway?,"Fenoprofen (also named Nalfon) is a nonsteroidal anti-inflammatory drug. Fenoprofen can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of Fenoprofen."
What is the definition of Flurbiprofen Action Pathway?,"Flurbiprofen (also named Ansaid or Froben) is a nonsteroidal anti-inflammatory drugs. It is used for treatment of moderate pain. Flurbiprofen can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of flurbiprofen."
What is the definition of Magnesium Salicylate Action Pathway?,"Magnesium Salicylate is a nonsteroidal anti-inflammatory drug. It can be used to treat mild to moderate muscular pain such as headaches, general back pain and other joint pain. Magnesium Salicylate can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of Magnesium Salicylate."
What is the definition of Lumiracoxib Action Pathway?,"Lumiracoxib (also named Prexige) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used as the mediators of certain kinds of intraocular inflammation. Lumiracoxib can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. "
What is the definition of Lornoxicam Action Pathway?,"Lornoxicam (also named Chlortenoxicam or Xefocam) is a nonsteroidal anti-inflammatory drug. It can be used to treat moderate pain such as pain relieving. It can also treat swelling and fever reducing. Lornoxicam can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of Lornoxicam."
What is the definition of Phenylbutazone Action Pathway?,"Phenylbutazone (also named fenilbutazona or butazolidin or bute) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat the pain and fever in animal. However, Phenylbutazone is not approved in United State and United Kingdom for human use anymore because of severe adverse effects. Phenylbutazone can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of phenylbutazone."
What is the definition of Nepafenac Action Pathway?,"Nepafenac (also named nevanac or ilevro or amfenac amide)  is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat pain and inflammation that is associated with cataract surgery. Nepafenac can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of nepafenac."
What is the definition of Trisalicylate-Choline Action Pathway?,"Trisalicylate-Choline (also named Choline Magnesium Trisalicylate) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat pain and fever. Trisalicylate-Choline can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of trisalicylate-choline."
What is the definition of Tolmetin Action Pathway?,"Tolmetin (also named Tolectin) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to reduce pain, swelling, tenderness, and stiffness. Tolmetin can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of tolmetin."
What is the definition of Tiaprofenic Acid Action Pathway?,"Tiaprofenic Acid (also named tiaprofensaeure and surgam) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat pain (especially arthritic pain). Tiaprofenic can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of tiaprofenic."
What is the definition of Tenoxicam Action Pathway?,"Tenoxicam (also named mobiflex and tilcotil) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to reduce inflammation, swelling, stiffness, and pain that are associated with various diseases such as tendinitis, bursitis and etc. Tenoxicam can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of tenoxicam."
What is the definition of Salsalate Action Pathway?,"Salsalate (also named Salflex, Disalcid or Salsitab) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used to treat pain, fever and inflammation. Salsalate can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of salsalate."
What is the definition of Salicylate-Sodium Action Pathway?,"Salicylate-sodium (also named salsonin or clin) is a nonsteroidal anti-inflammatory drug (NSAID). It can be used for relieving pain and reducing fever. Salicylate-sodium can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of salicylate-sodium."
What is the definition of Salicylic Acid Action Pathway?,"Salicylic acid (also named rutranex or salonil) is a nonsteroidal anti-inflammatory drug. Salicylic acid is also an important active metabolite of aspirin (acetylsalicylic acid). It can be used to reduce pain and fever. Salicylic acid can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of Salicylic acid."
What is the definition of Acetaminophen  Action Pathway?,"Acetaminophen (also named paracetamol or APAP) is not a Nonsteroidal anti-inflammatory drugs (NSAIDs). However, it still can be used to treat pain and fever. Acetaminophen can block prostaglandin synthesis by the action of inhibition of prostaglandin G/H synthase 1 and 2. Prostaglandin G/H synthase 1 and 2 catalyze the arachidonic acid to prostaglandin G2, and also catalyze prostaglandin G2 to prostaglandin H2 in the metabolism pathway. Decreased prostaglandin synthesis in many animal model's cell is caused by presence of acetaminophen."
What is the definition of Tobramycin Action Pathway?,"Tobramycin (also named aktob or tobi) is an aminoglycoside antibiotic that can be used to treat various gram-negative bacterial infections such as the species of Pseudomonas. Bacterial 30S ribosomal subunit protein and four nucleotides of 16S rRNA will be bound with tobramycin irreversibly to cause misreading of mRNA; so that formation of mRNA could be prevented because of incorrect insertion of amino acids to polypeptide will result nonfunctional or toxic peptides. Therefore, there is no protein synthesis for bacteria."
What is the definition of Tigecycline Action Pathway?,"Tigecycline is a glycylcycline, a class of antibiotics derived from tetracycline. Tigecycline has broad spectrum antibacterial abilities and is not susceptible to traditional tetracycline resistance mechanisms such as ribosomal protection and efflux by tetracycline-specific pumps. Tigecycline inhibits bacterial protein synthesis by binding to the A site of the 16s rRNA on the 30S ribosomal subunit. By binding to the A site, tigecycline prevents tRNA from docking onto the 16S rRNA with it’s codon ultimately halting the addition of amino acids to elongate peptide chains used in protein structures."
What is the definition of Arbekacin Action Pathway?,"Arbekacin, trade name Habekacin, is an aminoglycoside antibiotic derived from dibekacin that inhibits bacterial protein synthesis. Arbekacin is prescribed to patients with sepsis and pneumonia resulting from MRSA. Arbekacin binds the bacterial 50S and 30S ribosomal subunit proteins and prevents the formation of the initiation complex with messenger RNA. More specifically, Arbekacin binds four nucleotides of the 16S rRNA and a single amino acid of protein S12. This interferes with the decoding site in the vicinity of nucleotide 1400 in 16S rRNA of the 30S subunit. This region interacts with the wobble base of the anticodon of tRNA. This causes interference of the initiation complex, misreading of mRNA so that incorrect amino acids are inserted into the polypeptide leading to nonfunctional or toxic peptides, and the breakup of polysomes into nonfunctional monosomes. Arbekacin is effective at treating Gram-positive bacteria like Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative bacteria such as Pseudomonas aeruginosa. "
What is the definition of Paromomycin Action Pathway?,"Paromomycin (also known as Aminosidin) is an antimicrobial that can be used for treatment of various parasitic infections. By binding to the A site of ribosomal RNA complexes, paramomycin can lead to production of incorrect polypeptide chain in bacteria, which cause incorrect protein production and eventually, the death of bacteria. Therefore, paramomycin can kill bacteria by inhibiting their protein synthesis that lead to bacterial death."
What is the definition of Methylhistidine Metabolism?,"Methylhistidine is a modified amino acid that is produced in myocytes during the methylation of actin and myosin. It is also formed from the methylation of L-histidine, which takes the methyl group from S-adenosylmethionine and forms S-adenosylhomocysteine as a byproduct.After its formation in the myocytes, methylhistidine enters the blood stream and travels to the kidneys, where it is excreted in the urine.Methylhistidine is present in the blood and urine in higher concentrations after skeletal muscle protein breakdown, which can occur due to disease or injury. Because of this, it can be used to judge how much muscle breakdown is occurring. Methylhistidine levels are also affected by diet, and may differ between vegetarian diets and those containing meats."
What is the definition of Thyroid Hormone Synthesis?,"Thyroid hormone synthesis is a process that occurs in the thyroid gland in humans that results in the production of thyroid hormones which regulate many different processes in the body, such as metabolism, temperature regulation and growth/development. Thyroid hormone synthesis begins in the nucleus of a thyroid follicular cell, as thyroglobulin synthesis occurs here and is transported to the endoplasmic reticulum. From there, thyroglobulin transported through endocytosis into the intracellular space, and then transported through exocytosis to the follicle colloid. There, thyroglobulin is joined by iodide that has been transported from the blood, through the thyroid follicular cell and arrived in the the follicle colloid using pendrin, and hydrogen peroxide to be catalyzed by thyroid peroxidase, creating thyroglobulin + iodotyrosine. Then, iodide, hydrogen peroxide and thyroidperoxidase create thyroglobulin + 3,5-diiodo-L-tyrosine. Thyroglobulin+3,5-diiodo-L-tyrosine then joins with hydrogen peroxide and thyroid peroxidase to create thyroglobulin + 2-aminoacrylic acid and thyroglobulin+liothyronine. Thyroglobulin + liothyronine then goes through two processes, the first being its transportation into the cell and undergoing of proteolysis, which is followed by liothyronine being transported into the bloodstream. The second process is thyroglobulin + liothyronine being catalyzed by thyroid peroxidase and resulting in the production of thyroglobulin + thyroxine. Thyroglobulin + thyroxine is then transported back into the cell, undergoes proteolysis, and thyroxine alone is transported back out of the cell and into the bloodstream. "
What is the definition of Apparent Mineralocorticoid Excess Syndrome?,"Apparent mineralocorticoid excess (AME) is an autosomal recessive form of low-renin hypertension associated with low aldosterone, metabolic alkalosis, hypernatremia, and hypokalemia. The disorder is due to a congenital defect in 11-beta-hydroxysteroid dehydrogenase type II (HSD11B2) activity, resulting in decreased conversion of biologically active cortisol to inactive cortisone; this defect allows cortisol to act as a ligand for the mineralocorticoid receptor, resulting in sodium retention and volume expansion. There is a favorable therapeutic response to spironolactone (review by Ferrari, 2010)."
What is the definition of 3-beta-Hydroxysteroid Dehydrogenase Deficiency?,"3-beta (β)-hydroxysteroid dehydrogenase (HSD) deficiency is an inherited disorder that affects hormone-producing glands including the gonads (ovaries in females and testes in males) and the adrenal glands.Mutations in the HSD3B2 gene cause 3β-HSD deficiency. The HSD3B2 gene provides instructions for making the 3β-HSD enzyme. This enzyme is found in the gonads and adrenal glands. The 3β-HSD enzyme is involved in the production of many hormones, including cortisol, aldosterone, androgens, and estrogen. Cortisol has numerous functions such as maintaining energy and blood sugar levels, protecting the body from stress, and suppressing inflammation."
What is the definition of 2-Aminoadipic 2-Oxoadipic Aciduria?,"It is a metabolic disorder characterized by increased levels of 2-oxoadipate and 2-hydroxyadipate in the urine.  Patients can have mild to severe intellectual disability, muscular hypotonia, developmental delay, ataxia, and epilepsy.  Most cases are asymptomatic. "
What is the definition of 27-Hydroxylase Deficiency?,"Sterol 27-hydroxylase is a mitochondrial cytochrome P-450 species (CYP27) that catalyzes the first step in the degradation of steroid side chain in cholesterol to produce bile acids in the liver. When there are low concentrations of 27-Hydroxylase, patients will exhibit cerebrotendinous xanthomatosis, an autosomal recessive disorder characterized by the accumulation of cholestanol and cholesterol due to the inability to break down the lipids. The formation of xanthomas (deposits of lipids) in the nervous system and tendons will cause symptoms such as dementia, ataxia, and cataracts. Other symptoms may include damaged liver cells and body tissues."
What is the definition of 3-Phosphoglycerate Dehydrogenase Deficiency?,"3-Phosphoglycerate dehydrogenase deficiency is a disorder of L-serine biosynthesis that is characterized by congenital microcephaly, psychomotor retardation, and seizures.The disorder is caused by homozygous or compound heterozygous or homozygous mutation in the gene encoding phosphoglycerate dehydrogenase on chromosome 1p12. Defects in the gene lead to a decrease of Glycine and Serine."
"What is the definition of Cystinosis, Ocular Nonnephropathic?","Cystinosis, ocular nonnephropathic, a variant of the classic nephropathic type of cystinosis, is an autosomal recessive lysosomal storage disorder characterized by photophobia due to corneal cystine crystals but absence of renal disease (summary by Anikster et al., 2000). It is caused by mutation in the gene encoding cystinosin, which maps to chromosome 17p13."
What is the definition of Cystinuria?,"Cystinuria is an autosomal disorder characterized by impaired epithelial cell transport of cystine and dibasic amino acids (lysine, ornithine, and arginine) in the proximal renal tubule and gastrointestinal tract. The impaired renal reabsorption of cystine and its low solubility causes the formation of calculi in the urinary tract, resulting in obstructive uropathy, pyelonephritis, and, rarely, renal failure (summary by Barbosa et al., 2012). Cystinuria can be caused by mutation in the SLC3A1 amino acid transporter gene, which encodes the heavy subunit of the renal amino acid transporter and is located on chromosome 2p, and/or by mutation in the SLC7A9 gene, which encodes the light subunit and is located on chromosome 19."
"What is the definition of Folate Malabsorption, Hereditary?","Hereditary folate malabsorption is an autosomal recessive disorder characterized by signs and symptoms of folate deficiency that appear within a few months after birth. Infants exhibit low blood and cerebrospinal fluid folate levels with megaloblastic anemia, diarrhea, immune deficiency, infections, and neurologic deficits. Treatment with folate supplementation results in resolution of the signs and symptoms. The disorder is caused by impaired intestinal folate absorption and impaired transport of folate into the central nervous system (summary by Qiu et al., 2006). hereditary folate malabsorption is caused by homozygous or compound heterozygous mutation in the SLC46A1 gene on chromosome 17q11."
"What is the definition of Fructose Intolerance, Hereditary?","Fructose intolerance becomes apparent in infancy at the time of weaning, when fructose or sucrose is added to the diet. Clinical features include recurrent vomiting, abdominal pain, and hypoglycemia that may be fatal. Long-term exposure to fructose can result in liver failure, renal tubulopathy, and growth retardation. Older patients who survive infancy develop a natural avoidance of sweets and fruits. Hereditary fructose intolerance is caused by a mutation in the gene encoding aldolase B (also known as fructose-bisphosphate aldolase B or liver-type aldolase) which results in an accumulation of fructose-1-phosphate. The fructose bisphosphate aldolase class of enzymes catalyze two reactions: (1) the cleavage of 6-carbon fructose 1,6-bisphosphate (FBP) into the 3-carbon products dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (G3P) and (2) the cleavage of 6-carbon fructose 1-phosphate (F1P) the 3-carbon products glyceraldehyde and DHAP. Aldolase B, unlike the other aldolase isoenzymes, is preferentially expressed in the liver and catalyzes both reactions (showing no preference for either). Aldolases A and C both prefer FBP as a substrate molecule (PMID: 11679716). "
What is the definition of Rolitetracycline Action Pathway?,"Rolitetracycline is a broad spectrum second antibiotic formed by the N-aminomethylation of the carboxamide function of tetracycline. Classified as a second generation tetracycline due to it’s semi-synthesis, rolitetracycline like tetracycline inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit. This prevents tRNA from interacting with the ribosome ultimately halting the addition of amino acids to peptide chains used in protein synthesis."
What is the definition of Methacycline Action Pathway?,"Methacycline is a type of tettracycline antibiotic, which can inhibiting the aminoacyl-tRNA bind to mRNA-ribosome complex (16S part of 30S ribosomal subunit). Binding og mRNA-ribosome complex can prevent translation of RNA to protein which result in inhibtion of cell growth. "
What is the definition of Lincomycin Action Pathway?,"Lincomycin is a lincosamid antibiotic that can effectively aganist aerobic gram-positive cocci, aerobic gram-positive bacilli as well as anaerobic gram-positive sporeforming bacilli in vitro. Lincomycin is derived from yeast Streptomyces lincolnensis. Lincomycin can bind and inhibit 50S subunits of bacterial ribosomes to prevent protein synthesis, which result in cell death."
What is the definition of Chloramphenicol Action Pathway?,"Chloramphenicol, trade names Pentamycetin and Chloromycetin, is a broad spectrum antibiotic originally derived from Streptomyces venezuelae. It inhibits protein synthesis by binding the 50S ribosomal subunit to prevent bacterial growth. Bacterial resistance has occurred through decreased uptake or permeability, ribosomal mutation and inactivation by acetylation. Adverse side effects such as aplastic anemia, bone-marrow suppression or Gray syndrome in neonates and infants have resulted in limited use.  However, due to ampicillin-resistance bacterial meningitis there has been a renewed interest in the drug. "
What is the definition of Troleandomycin Action Pathway?,"Troleandomycin is a macrolide antibiotic that is similar to erythromycin. It is active in vitro against the following gram-positive organisms: Streptococcus pyogenes and Diplococcus pneumoniae. Troleandomycin acts by penetrating the bacterial cell membrane and reversibly binding to the 50 S subunit of bacterial ribosomes or near the ""P"" or donor site so that binding of tRNA (transfer RNA) to the donor site is blocked. Translocation of peptides from the ""A"" or acceptor site to the ""P"" or donor site is prevented, and subsequent protein synthesis is inhibited."
What is the definition of Josamycin Action Pathway?,"Josamycin is a macrolide antibiotic that is synthesized from Streptomyces narbonensis which can against various pathogens. Josamycin inhibits protein biosynthesis of bacteria by binding to ribosomal 50S subunit reversibly, which lead to inhibition of translocation of peptidyl tRNA. This action is mainly bacteriostatic, but can also be bactericidal in high concentrations. Macrolides can be accumulated within leukocytes, and transport into infection site later on."
What is the definition of Roxatidine Acetate Action Pathway?,"Roxatidine acetate is an anti-ulcer agent, that works through antagonizing the histamine H2 receptor. It is used to reduce abdominal pain, heartburn, acid indigestion and acid reflux. The pathway begins in the stomach, where roxatidine acetate inhibits the histamine H2 receptor on the surface of the parietal cell. Now in the gastric endothelial cell, potassium-transporting ATPase units are inhibited by G-Protein signalling cascade through somatostatin receptor type 4, which is activated by somatostatin. At the same time, potassium-transporting ATPase is activated by the G-protein signalling cascade, through histamine H2 receptor which is inhibited by ranitidine, gastrin/cholecystokinin type B receptor, and muscarinic acetylcholine receptor M3 which are activated by histamine, gastrin and acetylcholine, respectively. The potassium transporting ATPase also converts water and ATP to a phosphate molecule and ADP. Alongside the transporters, potassium is brought into the cell. Carbonic anhydrase 1 uses water and carbon dioxide to create hydrogen carbonate and a hydrogen ion, which are both transported out of the endothelial cell, into the gastric lumen. A chloride ion is transported into the gastric endothelial cell through a chloride anion exchanger and is transported out of the cell through a chloride intracellular channel protein 2, back into the gastric lumen."
What is the definition of Metiamide Action Pathway?,Metiamide is a histamine H2-receptor antagonist that can bind and inhibit histamine H2-receptor to prevent the histamine effects on basolateral memrbane in gastric parietal cell. Binding and inhibition of histamine H2-receptor can lead to decreased gastric acid secretion so that lowering gastric volume as well as acidity.
What is the definition of Betazole Action Pathway?,"Betazole, also known as ametazole and Histalog, is a histamine H2 agonist that causes an increase in gastric acid secretion. Betazole is commonly used to evaluate acid production. Betazole binds to the H2 receptor to enhance the G protein signaling cascade to increase gastric secretion into the lumen. Gastric acid digests protein and absorbs calcium, iron and vitamin B12. Gastric acidity may also interfere with medication bioavailability. Measuring gastric acid secretion is useful to manage diseases involving acid production such as gastroesophageal reflux disease. "
What is the definition of Abacavir Action Pathway?,"Abacavir (also known as Ziagen or Epzicom) is an antiviral agent that is used for treating HIV/AID. Cellular enzyme converts abacavir to its activate metabolite, carbovir triphosphate, for inhibiting HIV-1 reverse transcriptase (RT) by competing with dGTP, which is the natural substrate of RT. Without HIV-1 reverse transcriptase, complementary DNA (cDNA) could not be generated; therefore, viral DNA couldn't be completed."
What is the definition of Delavirdine Action Pathway?,"Delavirdine (also known as Rescriptor) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that can be used for treating HIV-1. Delavirdine can bind and inhibit the reverse transcriptase so that the DNA polymerase activities can be prevented, which lead to disruption of the enzyme's catalytic site and eventually lead to prevention of cell growth."
What is the definition of Didanosine Action Pathway?,"Didanosine (ddl) can be metabolized into dideoxyadenosine triphosphate (ddATP) by series of reaction. Dideoxyadenosine triphosphate can bind and inhibit HIV reverse transcriptase enzyme competitively against natural dATP. Dideoxyadenosine triphosphate will terminate the viral DNA chain to make it missing 3'-OH group so that formation of 5' to 3' phosphodiester could be prevented, which 5' to 3' phosphodiester is required for DNA chain elongation and result in terminated DNA growth."
What is the definition of Efavirenz Action Pathway?,"Efavirenz (also known as Sustiva) is a nucleoside reverse transcriptase inhibitor (NRTI) for treating HIV infection by inhibiting the transcriptase reversibly. Efavirenz is phosphorylated to its active triphosphorylated form so that it can compete with deoxycytidine 5'-triphosphate to inhibit HIV-1 reverse transcriptase, which lead to early chain termination. "
What is the definition of Emtricitabine Action Pathway?,"Emtricitabine (also known as FTC) is a nucleoside reverse transcriptase inhibitor (NRTI) for treating HIV infection by inhibiting the transcriptase reversibly. Emtricitabine is phosphorylated to form emtricitabine 5'-triphosphate so that emtricitabine 5'-triphosphate can compete with deoxycytidine 5'-triphosphate to inhibit HIV-1 reverse transcriptase, which lead to early chain termination. Emtricitabine 5'-triphosphate can also incorporate into viral DNA to inhibit the activity of HIV-1 reverse transcriptase (RT)."
What is the definition of Lamivudine  Action Pathway?,"Lamivudine (also known as 3TC) is an antiretroviral drug that can be used to treat HIV/AIDS. Lamivudine is phosphorylated to lamivudine triphosphate (L-TP), which is its active metabolite. Lamivudine triphosphate (L-TP) can bind and inhibit the HIV reverse transcriptase as well as HBV polymerase, which lead to DNA chain termination. "
What is the definition of Nevirapine  Action Pathway?,"Nevirapine (also named as Viramune or BIRG587) is a medication that are used for the treatment of HIV/AIDS (especially HIV-1). Nevirapine binds and inhibits reverse transcriptase to create interruption on catalytic site of enzyme so that it can prevent the activities of RNA-dependent and DNA-dependent DNA polymerase, which lead to no complementary DNA (cDNA) produced."
What is the definition of Rilpivirine Action Pathway?,"Rilpivirine, sold as Edurant, is an antiretroviral drug that works as a non-nucleoside reverse transcriptase inhibitor (NNRTI) to treat HIV infections.NNRTI drugs work by entering the cell that HIV is present in, and binding to HIV's reverse transcriptase protein. This inactivates it, preventing HIV from being able to produce cDNA from its RNA genome, effectively stopping it from replicating its genome and spreading. While NNRTIs are able to prevent HIV from replicating, it does not destroy the virus, and it is only useful to help slow down the progression of the disease, not curing it."
What is the definition of Stavudine Action Pathway?,"Acquired immunodeficiancy syndrome (AIDS) is generally accepted to be a consequence of infection with the retrovirus designated as human immunodeficiency virus (HIV-l). Stavudine is a potent and selective inhibitor of HIV-replication and of cytopathic effects in a variety of mammalian cells, and is relatively non-toxic to the uninfected human T-cell line H9. Stavudine, phosphorylates cellular enzymes to the mono-, di-, and triphosphates and is ultimately incorporated into the DNA of growing cells. A significant amount of radioactivity appears in the alkaline labile fraction of cells which are treated with Stavudine, due to terminal addition of Stavudine to DNA and the resultant chain termination."
What is the definition of Zalcitabine Action Pathway?,"Zalcitabine (ddc) is a dideoxynucleoside antiretroviral drug that when used in combination with zidovudine improves the viral load and CD4+ cell count of patients infected with Human Immunodeficiency Virus Type 1 (HIV-1). Zalcitabine is phosphorylated to it’s active form metabolite 2′,3′-dideoxycytidine 5′-triphosphate (ddCTP) in both healthy and infected cells. ddCTP competes with deoxycytidine triphosphate inhibiting the enzyme reverse transcriptase from using the substrates to elongate the viral DNA strand ultimately halting HIV replication."
What is the definition of Zidovudine Action Pathway?,"The discovery of AIDS prompted the search for agents that block the HIV replication process. Zidovudine (AZT) is a nucleoside analogue of thymidine, and was shown to reduce considerably the mortality of patients with AIDS. Zidovudine is toxic to the hemtopoietic system, causing anemia and neutropenia. It is clear, however, that disease progression can occur during continued administration of zidovudine. Moreover, zidovudine is not effective in treating Kaposi sarcoma, a common complication of HIV infection. Zidovudine therapy is also associated with a high incidence of toxicity, primarily bone marrow suppression, that requires dosage reduction or discontinuation of the therapy."
What is the definition of Activation of PKC Through G Protein-Coupled Receptor?,"G protein-coupled receptors sense stimuli outside the cell and transmit signals across the plasma membrane. Activation of protein kinase C (PKC) is one of the common signaling pathways. When a class of GPCRs are activated by a ligand, they activate Gq protein to bind GTP instead of GDP. After the Gq becomes active, it activates phospholipase C (PLC) to cleave the membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol 1,4,5-trisphosphate (IP3) and diacyl glycerol (DAG). IP3 can bind Ins3P receptor to open calcium channel by diffusion from cytoplasm to ER. Activated calcium channel will release the calcium from ER into cytoplasm. Calcium can activate the kinase activity of PKC."
"What is the definition of 2,3-Dihydroxybenzoate Biosynthesis?","2,3-Dihydroxybenzoate is synthesized from chorismate via isochorismate and 2,3-dihydroxy-2,3-dihydrobenzoate. Chorismate is a key intermediate and branch point in the biosynthesis of many aromatic compounds. The biosynthesis of 2,3-dihydroxybenzoate from chorismate is catalyzed by three enzymes: EntC, EntB, and EntA. EntC catalyzes the conversion of chorismate to isochorismate. The N-terminal isochorismate lyase domain of EntB hydrolyzes the pyruvate group of isochorismate to produce 2,3-dihydro-2,3-dihydroxybenzoate. The conversion of this latter compound to 2,3-dihydroxybenzoate is catalyzed by the EntA dehydrogenase."
What is the definition of Nitrogen Metabolism?,"Nitrogen and nitrogen cycle play an important role in biological process for many microorganisms as catalyzing different reactions. For example, nitrate reduction is used for conversion into ammonia and denitrification, where denitrification is an important cellular respiration process. Nitrogenase enzyme in prokaryotes can fix the atmospheric nitrogen by catalyzing nitrogen fixation (i.e. reduction of nitrogen to ammonia). Nitrate can be introduced into the cytoplasm through a nitrate:nitrite antiporter NarK or a nitrate/nitrite transporter NarU. Nitrate is then reduced by a nitrate reductase resulting in the release of water, an acceptor, and a nitrite. Nitrite can also be introduced into the cytoplasm through a nitrate:nitrite antiporter NarK. Nitrite can be reduced by an NADPH-dependent nitrite reductase resulting in water, NAD, and ammonia. Nitrite can interact with a hydrogen ion and ferrocytochrome c through a cytochrome c-552 ferricytochrome resulting in the release of ferricytochrome c, water, and ammonia. Another process by which ammonia is produced is by a reversible reaction of hydroxylamine with a reduced acceptor through a hydroxylamine reductase. This results in an acceptor, water, and ammonia. Water and carbon dioxide react through a carbonate dehydratase resulting in carbamic acid. This compound reacts spontaneously with hydrogen ion resulting in the release of carbon dioxide and ammonia. Carbon dioxide can interact with water through a carbonic anhydrase resulting in hydrogen carbonate. This compound interacts with cyanate and hydrogen ion through a cyanate hydratase resulting in a carbamic acid. Ammonia can be metabolized by reacting with L-glutamine and ATP-driven glutamine synthetase resulting in ADP, phosphate, and L-glutamine. The latter compound reacts with oxoglutaric acid and hydrogen ion through an NADPH-dependent glutamate synthase resulting in the release of NADP and L-glutamic acid. L-Glutamic acid reacts with water through an NADP-specific glutamate dehydrogenase resulting in the release of oxoglutaric acid, NADPH, hydrogen ion, and ammonia."
What is the definition of Fatty Acid Oxidation?,"Fatty acid oxidation is also known as beta-oxidation. Fatty acids are an important energy source because they are anhydrous and can be reduced. Fatty acids are good sources of energy as they yield more energy than carbohydrates. The fatty acid oxidation pathway degrades fatty acids into acetyl-CoA under anaerobic and aerobic conditions. Enzymes of this pathway can process short and long chain fatty acids. The first step in the pathway is the conversion of acyl-CoA to enoyl-CoA. The pathway continues in a cycle, each turn removing two carbon atoms from the input acyl-CoA to produce acetyl-CoA. Each turn also produces NADH. "
What is the definition of Biosynthesis of Siderophore Group Nonribosomal Peptides?,"2,3-Dihydroxybenzoate is synthesized from chorismate via isochorismate and 2,3-dihydroxy-2,3-dihydrobenzoate. The biosynthesis of 2,3-dihydroxybenzoate starts from chorismate being synthesized into isochorismate through isochorismate synthase entC. EntC catalyzes the conversion of chorismate into isochorismate. The N-terminal isochorismate lyase domain of EntB hydrolyzes the pyruvate group of isochorismate to produce 2,3-dihydro-2,3-dihydroxybenzoate. The conversion of this latter compound to 2,3-dihydroxybenzoate is catalyzed by the EntA dehydrogenase. This compound then interacts with L-serine and ATP through the enterobactin synthase protein complex resulting in the production of enterobactin. Enterobactin is exported into the periplasmic space through the enterobactin exporter entS. The compound is then exported into the environment through the outer membrane protein TolC. In the environment, enterobactin reacts with iron to produce ferric enterobactin. This compound is imported into the periplasmic space through a ferric enterobactin outer membrane transport complex. The compound then enters the cytoplasm through a ferric enterobactin ABC transporter. Once inside the cytoplasm, ferric enterobactin spontaneously releases the iron ion from the enterobactin. Alternatively, it can react with water through an enterochelin esterase resulting in the release of 2,3-dihydroxybenzoylserine, Fe3+, and hydrogen ions."
What is the definition of Biotin Metabolism?,"Biotin (vitamin H or vitamin B7) is the essential cofactor of biotin-dependent carboxylases, such as pyruvate carboxylase and acetyl-CoA carboxylase. In E. coli and many organisms, pimelate thioester is derived from malonyl-ACP. The pathway starts with a malonyl-[acp] interacting with S-adenosylmethionine through a biotin synthesis protein BioC resulting in an S-adenosylhomocysteine and a malonyl-[acp] methyl ester. The latter compound is then involved in the synthesis of a 3-ketoglutaryl-[acp] methyl ester through a 3-oxoacyl-[acyl-carrier-protein] synthase. The compound 3-ketoglutaryl-[acp] methyl ester is reduced by a NADPH-mediated 3-oxoacyl-[acyl-carrier-protein] reductase resulting in a 3R-hydroxyglutaryl-[acp] methyl ester. This compound is then dehydrated through a (3R)-hydroxymyristoyl-[acp] dehydratase producing an enoylglutaryl-[acp] methyl ester. This compound is then reduced through an NADPH mediated enoyl-acp-reductase [NADH] resulting in a glutaryl-[acp] methyl ester. This compound interacts with a malonyl-[acp] through a 3-oxoacyl-[acp] synthase 2 resulting in a 3-ketopimeloyl [acp] methyl ester. This compound is then reduced through an NADPH 3-oxoacyl [acp] reductase producing a 3-hydroxypimeloyl-[acp] methyl ester and then dehydrated by (3R)-hydroxymyristoyl-[acp] dehydratase to produce an enoylpimeloyl-[acp] methyl ester. This compound is then reduced by an NADPH-dependent enoyl-[acp]reductase resulting in a pimeloyl-[acp] methyl ester. This compound then reacts with water through a carboxylesterase resulting in a pimeloyl-[acp] and a methanol. The pimeloyl-acp reacts with L-alanine through an 8-amino-7-oxononanoate synthase resulting in 8-amino-7-oxononanoate which in turn reacts with S-adenosylmethionine through a 7,8-diaminonanoate transaminase resulting in an S-adenosyl-4-methylthio-2-oxobutanoate and 7,8-diaminononanoate. The latter compound is then dephosphorylated through a dethiobiotin synthetase resulting in a dethiobiotin. This compound interacts with a sulfurated[sulfur carrier), a hydrogen ion, and an S-adenosylmethionine through a biotin synthase to produce biotin and releasing L-methionine and a 5-deoxyadenosine. Biotin is then metabolized by a bifunctional protein resulting in pyrophosphate and biotinyl-5-AMP which in turn reacts with the same protein (bifunctional protein birA resulting in a biotin carboxyl carrying protein. This product then enters fatty acid biosynthesis."
What is the definition of D-Alanine Metabolism?,"L-Alanine is an essential component of protein and peptidoglycan. The latter also contains about three molecules of D-alanine for every L-alanine. Only about 10 percent of the total alanine synthesized flows into peptidoglycan. Please refer to L-alanine metabolism (pathway PW000788 or SMP0000810). In this pathway, D-amino acid dehydrogenase degrades D-alanine to form pyruvate, which the later will serve as source of carbon for central metabolism. D-alanine can be formed by either biosynthetic alanine racemase or catabolic alanine racemase. D-alanine is required for forming the cell wall peptidoglycan (murein). D-alanine is metabolized by ATP driven D-alanine ligase A and B resulting in D-alanyl-D-alanine. This product is incorporated into peptidoglycan biosynthesis."
What is the definition of D-Glutamine and D-Glutamate Metabolism?,"L-Glutamine is transported into the cytoplasm through a glutamine ABC transporter. Once inside, L-glutamine is metabolized with glutaminase to produce an L-glutamic acid. This process can be reversed through a glutamine synthetase resulting in L-glutamine. L-glutamic acid can also be transported into the cytoplasm through various methods: a glutamate/aspartate:H+ symporter GltP, a glutamate:sodium symporter, or a glutamate/aspartate ABC transporter. L-Glutamic acid can proceed to L-glutamate metabolism or it can undergo a reversible reaction through a glutamate racemase resulting in D-glutamic acid. This compound can also be obtained from D-glutamine interacting with a glutaminase. D-Glutamic acid reacts with UDP-N-acetylmuramoyl-L-alanine through an ATP-driven UDP-N-acetylmuramoylalanine-D-glutamate ligase resulting in a UDP-N-acetylmuramoyl-L-alanyl-D-glutamate which is then integrated into peptidoglycan biosynthesis. UDP-N-acetylmuramoyl-L-alanine comes from the amino sugar and nucleotide sugar metabolism product, UDP-N-acetylmuraminate which reacts with L-alanine through an ATP-driven UDP-N-acetylmuramate-L-alanine ligase."
What is the definition of Lipoic Acid Metabolism?,"Lipoic acid metabolism starts with caprylic acid being introduced into the cytoplasm, however, no transporter has been identified yet. Once caprylic acid is in the cytoplasm, it can react with a holo-acp through an ATP-driven 2-acylglycerophosphoethanolamine acyltransferase/acyl-ACP synthetase resulting in pyrophosphate, AMP, and octanoyl-[acp]. The latter compound can also be obtained from palmitate biosynthesis. Octanoyl-acp interacts with a lipoyl-carrier protein L-lysine through an octanoyltransferase resulting in a hydrogen ion, a holo-acyl-acp, and an N6-(octanoyl)lysine. The latter compound reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier], and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and protein N6-(octanoyl)lysine. Caprylic acid can also interact with ATP and a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, pyrophosphate, hydrogen ion, and protein N6-(octanoyl)lysine. The latter compound reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier] and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and a protein N6-(octanoyl)lysine. R-Lipoic acid can be absorbed from the environment, as seen in studies by Morris TW. In this pathway, the lipoyl-protein ligase LplA utilizes pre-existing lipoate that has been imported from outside the cell, and thus catalyzes a salvage pathway. Lipoic acid interacts with ATP and hydrogen ion through a lipoyl-protein ligase A, resulting in a pyrophosphate and a lipoyl-AMP (lipoyl-adenylate). This compound then interacts with a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, a hydrogen ion, and a protein N6-(lipoyl) lysine. It has been suggested that the conversion of octanoylated-domains into lipoylated ones described in this pathway may be a type of a repair pathway, activated only if the other lipoate biosynthetic pathways are malfunctioning."
What is the definition of Lysine Biosynthesis?,"Lysine is biosynthesized from L-aspartic acid. L-Aspartic acid can be incorporated into the cell through various methods: C4 dicarboxylate/orotate:H+ symporter, glutamate/aspartate:H+ symporter GltP, dicarboxylate transporter, C4 dicarboxylate/C4 monocarboxylate transporter DauA, and glutamate/aspartate ABC transporter. L-Aspartic acid is phosphorylated by an ATP-driven aspartate kinase resulting in ADP and L-aspartyl-4-phosphate. L-Aspartyl-4-phosphate is then dehydrogenated through an NADPH-driven aspartate semialdehyde dehydrogenase resulting in a release of phosphate, NADP, and L-aspartic 4-semialdehyde (involved in methionine biosynthesis). L-Aspartic 4-semialdehyde interacts with a pyruvic acid through a 4-hydroxy-tetrahydrodipicolinate synthase resulting in a release of hydrogen ion, water, and (2S,4S)-4-hydroxy-2,3,4,5-tetrahydrodipicolinate. The latter compound is then reduced by an NADPH-driven 4-hydroxy-tetrahydrodipicolinate reductase resulting in a release of water, NADP, and (S)-2,3,4,5-tetrahydrodipicolinate, This compound interacts with succinyl-CoA and water through a tetrahydrodipicolinate succinylase resulting in a release of coenzyme A and N-succinyl-2-amino-6-ketopimelate. This compound interacts with L-glutamic acid through an N-succinyldiaminopimelate aminotransferase resulting in oxoglutaric acid and N-succinyl-L,L-2,6-diaminopimelate. The latter compound is then desuccinylated by reacting with water through an N-succinyl-L-diaminopimelate desuccinylase resulting in a succinic acid and L,L-diaminopimelate. This compound is then isomerized through a diaminopimelate epimerase resulting in a meso-diaminopimelate (involved in peptidoglycan biosynthesis I). This compound is then decarboxylated by a diaminopimelate decarboxylase resulting in a release of carbon dioxide and L-lysine. L-Lysine is then incorporated into the lysine degradation pathway. Lysine also regulates its own biosynthesis by repressing dihydrodipicolinate synthase and also by repressing lysine-sensitive aspartokinase 3. Diaminopielate is a precursor for lysine as well as other cell wall components. Synthesis of lysine starts by converting L-aspartic acid (L-aspartate) to L-Aspartyl-4-phosphate by aspartate kinase. L-Aspartyl-4-phosphate transforms to form L-aspartic 4-semialdehyde (L-aspartate semialdehyde) by aspartate semialdehyde dehydrogenase with NADPH. L-aspartic 4-semialdehyde can start the metabolic pathway of synthesis of methionine as well as synthesis of threonine. Aspartate kinase can be regulated by its end product: L-Lysine."
What is the definition of Lysine Degradation I?,"Lysine is an essential amino acid that used for protein synthesis. Lysine can be transported into the cell by probable cadaverine (also known as lysine antiporter), or lysine can also be produced during lysine biosynthesis (from aspartic acid). Inside the cell, lysine is decarboxylated by lysine decarboxylase to cadaverine. Cadaverine can be transported out of cell through  probable cadaverine in later."
What is the definition of Taurine Metabolism?,"Taurine is incorporated into the cytoplasm through a taurine ABC transporter. Once inside the cytoplasm, taurine interacts with an oxoglutaric acid and an oxygen through a taurine dioxygenase resulting in the release of succinic acid, sulfite, aminoacetaldehyde, and carbon dioxide."
What is the definition of TCA Cycle?,"The citric acid cycle (also named tricarboxylic acid (TCA) cycle or the Krebs cycle), is a collection of 9 enzyme-catalyzed chemical reactions that occur in all living cells undergoing aerobic respiration. The citric acid cycle itself was officially identified in 1937 by Hans Adolf Krebs, who received the Nobel Prize for this discovery in 1953. In eukaryotes, the citric acid cycle occurs in the mitochondria. In prokaryotes, the TCA cycle occurs in the cytoplasm. The TCA cycle starts with acetyl-CoA, which is the “fuel” for the entire cycle. This important molecule comes from the breakdown of glycogen (a stored form of glucose), fats, and many amino acids. At beginning, acetyl-CoA first transfers its 2-carbon acetyl group to the 4-carbon acceptor compound called oxaloacetate to form the 6-carbon compound (citrate) for which the cycle is named. The resulting citrate will have numbers of chemical transformations, whereby it loses one carboxyl group (leading to the 5-carbon compound called alpha-ketoglutarate) and then a second carboxyl group (leading to the 4-carbon compound called succinate). Succinate molecule is further oxidized to fumarate, then malate and finally oxaloacetate. The regeneration of the 4-carbon oxaloacetate, allows the TCA cycle to continue. Oxidation step generates energy that is transferring energy-rich electrons for NAD+ to form NADH in TCA cycle. Each acetyl group will generate 3 NADH in TCA cycle."
What is the definition of Glycolysis and Pyruvate Dehydrogenase?,"Fructose metabolism begins with the transport of beta-D-glucose 6-phosphate through a glucose PTS permease. This compound is isomerized by a glucose-6-phosphate isomerase resulting in fructose 6-phosphate. This compound can be phosphorylated by two different enzymes: a pyridoxal phosphatase/fructose 1,6-bisphosphatase or an ATP-driven 6-phosphofructokinase-1, resulting in fructose 1,6-biphosphate. This compound can either react with a fructose bisphosphate aldolase class 1 resulting in D-glyceraldehyde 3-phosphate and dihydroxyacetone phosphate or through a fructose biphosphate aldolase class 2 resulting in D-glyceraldehyde 3-phosphate. This compound can then either react in a reversible triosephosphate isomerase resulting in dihydroxyacetone phosphate or react with a phosphate through an NAD-dependent glyceraldehyde 3-phosphate dehydrogenase resulting in glyceric acid 1,3-biphosphate. This compound is dephosphorylated by a phosphoglycerate kinase resulting in 3-phosphoglyceric acid. This compound, in turn, can either react with a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase or a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in 2-phospho-D-glyceric acid. This compound interacts with an enolase resulting in a phosphoenolpyruvic acid and water. Phosphoenolpyruvic acid can react either through an AMP-driven phosphoenoylpyruvate synthase or an ADP-driven pyruvate kinase protein complex resulting in pyruvic acid. The pyruvic acid reacts with CoA through an NAD-driven pyruvate dehydrogenase complex resulting in carbon dioxide and an acetyl-CoA which gets incorporated into the TCA cycle pathway."
What is the definition of Inner Membrane Transport?,"This pathway is a compilation of Escherichia coli inner membrane transport complexes that transport compounds from the periplasmic space into the cytosol. Many compound classes are carried by these inner membrane transport complexes including sugars, amino acids, and lipids."
What is the definition of Aspartate Metabolism?,"Aspartate is synthesized from and broken down to oxaloacetate, a TCA cycle intermediate, via a reversible transamination reaction with glutamate. This reaction is catalyzed by the aminotransferase AspC or TyrB. Aspartate is a component of proteins and is involved in many biosyntheses pathways like NAD biosynthesis and beta-alanine metabolism. Aspartate can also be synthesized from fumaric acid through an aspartate ammonia lyase. Aspartate also participates in the synthesis of L-asparagine through two different methods, either through aspartate ammonia ligase or asparagine synthetase B. Aspartate is also a precursor of fumaric acid. Again it has two possible ways of synthesizing it. First set of reactions follows an adenylo succinate synthetase that yields adenylsuccinic acid and then adenylosuccinate lyase  in turns leads to fumaric acid. The second way is through argininosuccinate synthase that yields argininosuccinic acid and then argininosuccinate lyase in turns leads to fumaric acid."
What is the definition of L-Alanine Metabolism?,"L-alanine is an essential component of proteins and peptidoglycan. The latter also contains about three molecules of D-alanine for every L-alanine. Only about 10 percent of the total alanine synthesized flows into peptidoglycan.There are at least 3 ways to begin the biosynthesis of alanine. The first method for alanine biosynthesis begins with L-cysteine produced from L-cysteine biosynthesis pathway. L-cysteine reacts with an [L-cysteine desulfurase] L-cysteine persulfide through a cysteine desulfurase resulting in a release of [L-cysteine desulfurase] l-cysteine persulfide and L-alanine. The second method starts with pyruvic acid reacting with L-glutamic acid through a glutamate-pyruvate aminotransferase resulting in a oxoglutaric acid and L-alanine.The third method starts with L-glutamic acid interacting with Alpha-ketoisovaleric acid through a valine transaminase resulting in an oxoglutaric acid and L-valine. L-valine reacts with pyruvic acid through a valine-pyruvate aminotransferase resulting Alpha-ketoisovaleric acid and L-alanine. This first step of the pathway, which can be catalyzed by either of two racemases( biosynthetic or catabolic), also serves an essential role in biosynthesis because its product, D-alanine, is an essential component of cell wall peptidoglycan (murein).  The first step of pathway is utilized by either biosynthetic alanine racemase (prodeminate) or catabolic alanine racemase, which convert L-alanine to D-alanine, an important component of cell wall peptidoglycan (murein). D-alanine  is metabolized  by an ATP driven D-alanine ligase A and B resulting in D-alanyl-D-alanine. This product is incorporated into the peptidoglycan biosynthesis. L-alanine is metabolized with alanine racemase, either catabolic or metabolic resulting in a D-alanine. This compound reacts with water and a quinone through a D-amino acid dehydrogenase  resulting in Pyruvic acid, hydroquinone and ammonium, thus entering the central metabolism and thereby can serve as a total source of carbon and energy. The role of the dadX racemase is degradative and dadX racemase can be induced by alanine and is subject to catabolite repression."
What is the definition of L-Glutamate Metabolism?,"There are various ways by which glutamate enters the cytoplasm in E.coli. through a glutamate:sodium symporter, glutamate / aspartate : H+ symporter GltP or aglutamate / aspartate ABC transporter. There are various ways by which E. coli synthesizes glutamate from L-glutamine or oxoglutaric acid. L-glutamine, introduced into the cytoplasm by glutamine ABC transporter, can either interact with glutaminase resulting in ammonia and L-glutamic acid, or react with oxoglutaric acid, and hydrogen ion through an NADPH driven glutamate synthase resulting in L-glutamic acid. L-glutamic acid is metabolized into L-glutamine  by reacting with ammonium through a ATP driven glutamine synthase. L-glutamic acid can also be metabolized into L-aspartic acid by reacting with oxalacetic acid through an aspartate transaminase  resulting in n oxoglutaric acid and L-aspartic acid. L-aspartic acid is metabolized into fumaric acid through an aspartate ammonia-lyase. Fumaric acid can be introduced into the cytoplasm through 3 methods: dicarboxylate transporter, C4 dicarboxylate / C4 monocarboxylate transporter DauA, and C4 dicarboxylate / orotate:H+ symporter."
What is the definition of Arginine Metabolism?,"The metabolism of L-arginine starts with the acetylation of L-glutamic acid resulting in a N-acetylglutamic acid while releasing a coenzyme A and a hydrogen ion. N-acetylglutamic acid is then phosphorylated via an ATP driven acetylglutamate kinase which yields a N-acetyl-L-glutamyl 5-phosphate. This compound undergoes a NDPH dependent reduction resulting in N-acetyl-L-glutamate 5-semialdehyde. This compound reacts with L-glutamic acid through a acetylornithine aminotransferase / N-succinyldiaminopimelate aminotransferase to produce  a N-acetylornithine which is then deacetylated through a acetylornithine deacetylase which yield an ornithine.L-glutamine is used to synthesize carbamoyl phosphate through the interaction of L-glutamine, water, ATP, and hydrogen carbonate. This reaction yields ADP, L-glutamic acid, phosphate, and hydrogen ion. Carbamoyl phosphate and ornithine are used to catalyze the production of citrulline through an ornithine carbamoyltransferase. Citrulline reacts with L-aspartic acid through an ATP dependent enzyme, argininosuccinate synthase to produce pyrophosphate, AMP and argininosuccinic acid. Argininosussinic acid is then lyase to produce L-arginine and fumaric acid.L-arginine can be metabolized into succinic acid by two different sets of reactions:1. Arginine reacts with succinyl-CoA through a arginine N-succinyltransferase resulting in N2-succinyl-L-arginine while releasing CoA and Hydrogen Ion. N2-succinyl-L-arginine is then dihydrolase to produce a N2-succinyl-L-ornithine through a N-succinylarginine dihydrolase. This compound in turn reacts with oxoglutaric acid through succinylornithine transaminase resulting in L-glutamic acid and N2-succinyl-L-glutamic acid 5-semialdehyde. This compoud in turn reacts with a NAD dependent dehydrogenase resulting in N2-succinylglutamate while releasing NADH and hydrogen ion. N2-succinylglutamate reacts with water through a succinylglutamate desuccinylase resulting in  L-glutamic acid and a succinic acid. The succinic acid is then incorporated in the TCA cycle2.Argine reacts with carbon dioxide and a hydrogen ion through a biodegradative arginine decarboxylase, resulting in Agmatine. This compound is then transformed into putrescine by reacting with water and an agmatinase, and releasing urea. Putrescine can be metabolized by reaction with either l-glutamic acid or oxoglutaric acid. If putrescine reacts with L-glutamic acid, it reacts through an ATP mediated gamma-glutamylputrescine producing a hydrogen ion, ADP, phosphate and gamma-glutamyl-L-putrescine. This compound is reduced by interacting with oxygen, water and a gamma-glutamylputrescine oxidoreductase resulting in ammonium, hydrogen peroxide and 4-gamma-glutamylamino butanal. This compound is dehydrogenated through a NADP mediated reaction  lead by gamma-glutamyl-gamma-aminobutaryaldehyde dehydrogenase resulting in  hydrogen ion, NADPH and 4-glutamylamino butanoate. In turn, the latter compound reacts with water through a gamma-glutamyl-gamma-aminobutyrate hydrolase resulting in L-glutamic acid and Gamma aminobutyric acid. On the other hand, if putrescine reacts with oxoglutaric acid through a putrescine aminotransferase, it results in L-glutamic acid, and a 4-aminobutyraldehyde. This compound reacts with water through a NAD dependent gamma aminobutyraldehyde dehydrogenase resulting in hydrogen ion, NADH and gamma-aminobutyric acid.Gamma Aaminobutyric acid reacts with oxoglutaric acid through 4-aminobutyrate aminotransferase resulting in L-glutamic acid and succinic acid semialdehyde. This compound in turn can react with with either NADP  or NAD to result in the production of succinic acid through succinate-semialdehyde dehydrogenase or aldehyde dehydrogenase-like protein yneI respectively. Succinic acid can then be integrated in the TCA cycle. L-arginine is eventua lly metabolized into succinic acid which then goes to the TCA cycle"
What is the definition of Ornithine Metabolism?,"In the ornithine biosynthesis pathway of E. coli, L-glutamate is acetylated to N-acetylglutamate by the enzyme N-acetylglutamate synthase, encoded by the argA gene. The acetyl donor for this reaction is acetyl-CoA. N-acetylglutamic acid is then phosphorylated via an ATP driven acetylglutamate kinase which yields a N-acetyl-L-glutamyl 5-phosphate. This compound undergoes a NADPH dependent reduction resulting in N-acetyl-L-glutamate 5-semialdehyde. This compound reacts with L-glutamic acid through a acetylornithine aminotransferase / N-succinyldiaminopimelate aminotransferase to produce  a N-acetylornithine which is then deacetylated through a acetylornithine deacetylase which yield an ornithine. Ornithine interacts with hydrogen ion  through a Ornithine decarboxylase resulting in a carbon dioxide release and a putrescine. Putrescine can be metabolized by reaction with either l-glutamic acid or oxoglutaric acid. If putrescine reacts with L-glutamic acid, it reacts through an ATP mediated gamma-glutamylputrescine producing a hydrogen ion, ADP, phosphate and gamma-glutamyl-L-putrescine. This compound is reduced by interacting with oxygen, water and a gamma-glutamylputrescine oxidoreductase resulting in ammonium, hydrogen peroxide and 4-gamma-glutamylamino butanal. This compound is dehydrogenated through a NADP mediated reaction  lead by gamma-glutamyl-gamma-aminobutaryaldehyde dehydrogenase resulting in  hydrogen ion, NADPH and 4-glutamylamino butanoate. In turn, the latter compound reacts with water through a gamma-glutamyl-gamma-aminobutyrate hydrolase resulting in L-glutamic acid and Gamma aminobutyric acid. On the other hand, if putrescine reacts with oxoglutaric acid through a putrescine aminotransferase, it results in L-glutamic acid, and a 4-aminobutyraldehyde. This compound reacts with water through a NAD dependent gamma aminobutyraldehyde dehydrogenase resulting in hydrogen ion, NADH and gamma-aminobutyric acid. Gamma Aaminobutyric acid reacts with oxoglutaric acid through 4-aminobutyrate aminotransferase resulting in L-glutamic acid and succinic acid semialdehyde. This compound in turn can react with with either NADP  or NAD to result in the production of succinic acid through succinate-semialdehyde dehydrogenase or aldehyde dehydrogenase-like protein yneI respectively. Succinic acid can then be integrated in the TCA cycle."
What is the definition of Ascorbate Metabolism?,"E. coli is able to utilize L-ascorbate (vitamin C) as the sole source of carbon under anaerobic and aerobic conditions.Ascorbic acid in the cytoplasm is processed through a spontaneous reaction with a hydrogen ion and hydrogen peroxide, producing water, dehydroascorbic acid and ascorbic acid. Dehydroascorbic acid reacts with water spontaneously producing an isomer, dehydroascorbate (bicyclic form). The compound then loses a hydrogen ion resulting in a 2,3-Diketo-L-gulonate. This compound is then reduced through a NADH dependent 2,3 diketo-L-gulonate reductase, releasing a NAD and 3-Dehydro-L-gulonate.This compound is phosphorylated through an ATP mediated L-xylulose/3-keto-L-gulonate kinase resulting in an ADP, hydrogen ion and a 3-Keto-L-gulonate 6 phosphate.L-ascorbate can also be imported and converted to L-ascorbate-6-phosphate by the L-ascorbate PTS transporter. L-ascorbate-6-phosphate reacts with a probable L-ascorbate-6-phosphate lactonase ulaG, resulting in a 3-keto-L-gulonate 6-phosphate.  The compound 3-keto-L-gulonate 6-phosphate can be processed aerobically or anaerobically.Aerobic:3-keto-L-gulonate 6-phosphate is decarboxylated by a 3-keto-L-gulonate-6-phosphate decarboxylase ulaD, releasing carbon dioxide and L-xylulose-5-phosphate. This compound in turn is changed into an isomer by L-ribulose-5-phosphate 3-epimerase ulaE, resulting in L-ribulose 5-phosphate. This compound again changes into a different isomer through a L-ribulose-5-phosphate 4-epimerase ulaF resulting in Xylulose 5-phosphate. This compound can then be part of the pentose phosphate pathway.Anaerobic:3-keto-L-gulonate 6-phosphate is decarboxylated by 3-keto-L-gulonate 6-phosphate decarboxylase sgbH, releasing carbon dioxide and L-xylulose-5-phosphate. This compound in turn is changed into an isomer by predicted L-xylulose 5-phosphate 3-epimerase, resulting in L-ribulose 5-phosphate. This compound again changes into a different isomer through a  L-ribulose-5-phosphate 4-epimerase resulting in Xylulose 5-phosphate. This compound can then be part of the pentose phosphate pathway.Expression of the ula regulon is regulated by the L-ascorbate 6-phosphate-binding repressor UlaR and by cAMP-CRP.Under aerobic conditions, metabolism of L-ascorbate is hindered by the special reactivity and toxicity of this compound in the presence of oxygen."
What is the definition of Proline Metabolism?,"The biosynthesis of L-proline in E. coli involves L-glutamic acid being phosphorylated through an ATP driven glutamate 5-kinase resulting in a L-glutamic acid 5-phosphate. This compound is then reduced through a NADPH driven gamma glutamyl phosphate reductase resulting in the release of a phosphate, a NADP and a L-glutamic gamma-semialdehyde. L-glutamic gamma-semialdehyde is dehydrated spontaneously, resulting in a release of water,hydrogen ion and 1-Pyrroline-5-carboxylic acid. The latter compound is reduced by an NADPH driven pyrroline-5-carboxylate reductase  which is subsequently reduced to L-proline. L-proline works as a repressor of the pyrroline-5-carboxylate reductase enzyme and glutamate 5-kinase. In E. coli, the biosynthesis of L-proline from L-glutamate is governed by three genetic loci namely proB, proA and proC. The first reaction in the pathway is catalyzed by γ-glutamyl kinase, encoded by proB . The second reaction, NADPH-dependent reduction of γ-glutamyl phosphate to glutamate-5-semialdehyde, in the pathway is catalyzed by glutamate-5-semialdehyde dehydrogenase, encoded by proA . These two enzymes aggregate into a multimeric bi-functional enzyme complex known as γ-glutamyl kinase-GP-reductase multienzyme complex. It is believed that the complex formation serves to protect the highly labile glutamyl phosphate from the hostile nucleophilic and aqueous environment found in the cell . The final step in the pathway, the reduction of pyrroline 5-carboxylate to L-proline, is catalyzed by an NADPH-dependent pyrroline-5-carboxylate reductase encoded by proC. Proline is  metabolized by being converted back to L-glutamate, which is further degraded to α-ketoglutarate, an intermediate of the TCA cycle. Curiously, L-glutamate, the obligate intermediate of the proline degradation pathway, cannot itself serve as a total source of carbon and energy for E. coli, because glutamate transport supplies exogenous glutamate at an inadequate rate. The process by which proline is turned into L-glutamate starts with L-proline interacting with ubiquinone through a bifunctional protein putA resulting in an ubiquinol, a hydrogen ion and a 1-pyrroline-5-carboxylic acid. The latter compound is then hydrated spontaneously resulting in a L-glutamic gamma-semialdehyde. This compound is then processed by interacting with water through an NAD driven bifunctional protein putA resulting in a hydrogen ion, NADH and L-glutamic acid."
What is the definition of D-Glucarate and D-Galactarate Degradation?,"Galactarate is a naturally occurring dicarboxylic acid analog of D-galactose. E. coli can use both diacid sugars galactarate and D-glucarate as the sole source of carbon for growth. The initial step in the degradation of galactarate is its dehydration to 5-dehydro-4-deoxy-D-glucarate(2--) by galactarate dehydratase. Glucaric acid can also be dehydrated by a glucarate dehydratase resulting in water and 5-dehydro-4-deoxy-D-glucarate(2--). The  5-dehydro-4-deoxy-D-glucarate(2--)  is then metabolized by a alpha-dehydro-beta-deoxy-D-glucarate aldolase resulting in pyruvic acid and a tartonate semialdehyde. Pyruvic acid interacts with coenzyme A through a NAD driven Pyruvate dehydrogenase complex resulting in a carbon dioxide, an NADH and an acetyl-CoA. The tartronate semialdehyde interacts with a hydrogen ion through a NADPH driven tartronate semialdehyde reductase resulting in a NADP and a glyceric acid. The glyceric acid is phosphorylated by an ATP-driven glycerate kinase 2 resulting in an ADP, a hydrogen ion and a 2-phosphoglyceric acid. The latter compound is dehydrated by an enolase resulting in the release of water and a phosphoenolpyruvic acid. The phosphoenolpyruvic acid interacts with a hydrogen ion through an ADP driven pyruvate kinase resulting in an ATP and a pyruvic acid. The pyruvic acid then interacts with water and an ATP through a phosphoenolpyruvate synthetase resulting in the release of a hydrogen ion, a phosphate, an AMP and a Phosphoenolpyruvic acid."
What is the definition of Fatty Acid Metabolism?,"Fatty acids constitute a large energy source for the body.  The cellular membrane is also made up of fatty acids.  Fatty acid metabolism is also known as beta-oxidation.  During metabolism, acetyl CoA is produced that can then enter the citric acid cycle.  When ATP is needed, ATP may be generated by increasing fatty acid metabolism.  Fatty acid metabolism is essentially the reverse reaction of fatty acid synthesis.  . "
What is the definition of Palmitate Biosynthesis ?,"Palmitate is synthesized by stepwise condensation of C2 units to a growing acyl chain. Each elongation cycle results in the addition of two carbons to the acyl chain, and consists of four separate reactions.The pathway starts with acetyl-CoA interacting with hydrogen carbonate through an ATP driven acetyl-CoA carboxylase resulting in a phosphate, an ADP , a hydrogen ion and a malonyl-CoA. The latter compound interacts with a holo-[acp] through a malonyl-CoA-ACP transacylase resulting in a CoA and a malonyl-[acp]. This compound interacts with hydrogen ion, acetyl-CoA through a  KASIII resulting in a CoA, carbon dioxide and an acetoacetyl-[acp]. The latter compound interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxybutanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a crotonyl-[acp](2).The crotonyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a butyryl-[acp](3).The butyryl-[acp] interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-hexanoyl-[acp](4).The  3-oxo-hexanoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxyhexanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans hex-2-enoyl-[acp](2).The  trans hex-2-enoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a hexanoyl-[acp](3).The hexanoyl-[acp] interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-octanoyl-[acp](4).The 3-oxo-octanoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxyoctanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans oct-2-enoyl-[acp](2).The trans oct-2-enoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a octanoyl-[acp](3).The octanoyl-[acp] interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-decanoyl-[acp](4).The 3-oxo-decanoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxydecanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans-delta2-decenoyl-[acp](2).The a trans-delta2-decenoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a decanoyl-[acp](3).The decanoyl-[acp] interacts with a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-dodecanoyl-[acp](4).The 3-oxo-dodecanoyl-[acp ]interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxydodecanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans dodec-2-enoyl-[acp](2).The  trans dodec-2-enoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a dodecanoyl-[acp](3). This compound can either react with water  spontaneously resulting in a hydrogen ion, a holo-[acp] and a dodecanoic acid or  it interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-myristoyl-[acp](4).The 3-oxo-myristoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (3R) 3-Hydroxymyristoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans tetradec-2-enoyl-[acp](2).This compound interacts with a hydrogen ion, through a NADH-driven KASI resulting in a NAD and a myristoyl-[acp].Myristoyl-[acp] with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-palmitoyl-[acp](4).The 3-oxo-palmitoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (3R) 3-Hydroxypalmitoyl-[acp](1).This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans hexadecenoyl-[acp](2).The  trans hexadecenoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a palmitoyl-[acp](3). Palmitoyl then reacts with water spontaneously resulting in a hydrogen ion, a holo-[acp] and palmitic acid.No integral membrane protein required for long chain fatty acid uptake has been identified in E. coli. The transport of long chain fatty acids across the cytoplasmic membrane is dependent on fatty acyl-CoA synthetase. An energised membrane is necessary for fatty acid transport and it has been suggested that uncharged fatty acids flip across the inner membrane by diffusion."
What is the definition of Fatty Acid Elongation (Saturated)?,"The fatty acid elongation pathway shows an elongation cycle of an acyl-ACP chain by adding two carbons. Acetoacetyl-acp is produced from interaction of 3-oxoacyl-acp synthase 3 with malonyl-acp and Acetyl-CoA, and then Acetoacetyl-acp produce a 3-oxoacyl acp spontaneously. 3-oxoacyl acp will undergo the cycles of the elongation. The first step is converting the oxoacyl acp into a (3R) 3-hydroxyacyl(acp) through a 3-oxoacyl[acp] reductase.This second step converts the hydroxyacyl into a trans 2 enoyl acp through a protein complex conformed of a hydroxomyristoyl dehydratase and a hydroxydecanoyl dehydratase. The third step can be reached through two different reactions with a enoyl-acp reductase, involving NADPH or NADH. This leads to the production of a 2,3,4-saturated fatty acyl acp. For the final step the 2,3,4 fatty acyl acp is turned into a oxoacyl acp through a 3-oxoacyl acp synthase protein complex. The products of multiple of the elongation cycle are phospholipids, lipoproteins (saturated fatty acids), lauric and other fatty acid-containing compounds."
What is the definition of tRNA Charging?,"This pathway is a compilation of Escherichia coli tRNA charging reactions involving amino acids transported into the cell. The aminoacyl-tRNA synthetase is an enzyme that attaches the appropriate amino acid onto its tRNA by catalyzing the esterification of a specific cognate amino acid or its precursor to one of all its compatible cognate tRNAs to form an aminoacyl-tRNA, which plays an important role in RNA translation. 20 different Aminoacyl-tRNA synthetases can make 20 different types of aa-tRNA for each amino acid according to the genetic code.  This process is called ""charging"" or ""loading"" the tRNA with amino acid. Ribosome can transfer the amino acid from tRNA to a growing peptide after the tRNA is charged. "
What is the definition of Cysteine Biosynthesis ?,The pathway of cysteine biosynthesis is a two-step conversion starting from L-serine and yielding L-cysteine. L-serine biosynthesis is shown for context. L-cysteine can also be synthesized from sulfate derivatives. The process through L-serine involves a serine acetyltransferase that produces a O-acetylserine which reacts together with hydrogen sulfide through a cysteine synthase complex in order to produce L-cysteine and acetic acid. Hydrogen sulfide is produced from a sulfate. Sulfate reacts with sulfate adenylyltransferase to produce adenosine phosphosulfate. This compound in turn is phosphorylated through a adenylyl-sulfate kinase into a phosphoadenosine phosphosulfate which in turn reacts with a phosphoadenosine phosphosulfate reductase to produce a sulfite. The sulfite reacts with a sulfite reductase to produce the hydrogen sulfide. This pathway shows the second step of cysteine biosynthesis (at genetic level).  Both cysteine synthase isozymes undergo the positive control by the cysteine-responsive transcription factor CysB. Only cysteine synthase A (CysK) forms a complex with serine acetyltransferase and it is the only cysteine synthase that is required for cell viability with cysteine-free medium. Cysteine synthases may also work as the sulfur scavenging systemfor sulfur starvation by taking sulfur off of L-cysteine. 
What is the definition of tRNA Charging 2?,"This pathway is a compilation of Escherichia coli tRNA charging reactions involving biosynthesized amino acids. The aminoacyl-tRNA synthetase is an enzyme that attaches the appropriate amino acid onto its tRNA by catalyzing the esterification of a specific cognate amino acid or its precursor to one of all its compatible cognate tRNAs to form an aminoacyl-tRNA, which plays an important role in RNA translation. 20 different Aminoacyl-tRNA synthetases can make 20 different types of aa-tRNA for each amino acid according to the genetic code.  This process is called ""charging"" or ""loading"" the tRNA with amino acid. Ribosome can transfer the amino acid from tRNA to a growing peptide after the tRNA is charged. "
What is the definition of Tyrosine Biosynthesis?,"The tyrosine biosynthesis pathways is connected with the chorismate biosynthesis pathway. Chorismate biosynthesis produce the chorismate, which further be converted to prephenate by T-protein. Combined with cofactor, NAD, prephenate has been further converted to 4-Hydroxyphenylpyruvic acid by T-protein with generated NADH and carbon dioxide. Tyrosine aminotransferase catalyzes 4-Hydroxyphenylpyruvic acid to tyrosine, and also convert glutamic acid to oxoglutaric acid. Tyrosine will be further catalyzed into various molecules such as 2-iminoacetate, p-Cresol, 5'Deoxyadenosine and L-Methionine; or it will be exported from cell via lysine exporter. "
What is the definition of Phenylalanine Biosynthesis?,"The phenylalaline biosynthesis pathways is connected with the chorismate biosynthesis pathway. Chorismate biosynthesis produce the chorismate, which further be converted to prephenate by P-protein. Combined with cofactor, H+, prephenate has been further converted to phenylpyruvic acid by P-protein with generated water and carbon dioxide. Phenylalanine transaminase catalyzes phenylpyruvic acid to phenylalaline, and also convert glutamic acid to oxoglutaric acid. Phenylalaline will be further used in phenylalaline metabolism."
What is the definition of Glycine Biosynthesis?,"One step pathway for glycine biosynthesis dependent on L-serine, is a major source of one-carbon units in the form of 5,10-methylene tetrahydrofolate. L-serine is enters cell through transporters (serine / threonine:H+ symporter TdcC, serine/threonine: Na symporter , serine:H+ symporter SdaC )  and then proceeds through reversible reaction with a tetrahydrofolic acid through a serine hydroxymethyltransferase enzyme in order to produce glycine, 5,10-methylene tetrahydrofolate and water"
What is the definition of Serine Biosynthesis and Metabolism?,"Serine biosynthesis is a major metabolic pathway in E. coli. Its end product, serine, is not only used in protein synthesis, but also as a precursor for the biosynthesis of glycine, cysteine, tryptophan, and phospholipids. In addition, it directly or indirectly serves as a source of one-carbon units for the biosynthesis of various compounds. The biosynthesis of serine starts with 3-phosphoglyceric acid being metabolized by a NAD driven D-3-phosphoglycerate dehydrogenase / α-ketoglutarate reductase resulting in the release of a NADH, a hydrogen ion and a phosphohydroxypyruvic acid. The latter compound then interacts with an L-glutamic acid through a 3-phosphoserine aminotransferase / phosphohydroxythreonine aminotransferase resulting in oxoglutaric acid and DL-D-phosphoserine.The DL-D-phosphoserine can also be imported into the cytoplasm through a phosphonate ABC transporter. The DL-D-phosphoserine is dephosphorylated by interacting with a water molecule through a phosphoserine phosphatase resulting in the release of a phosphate and an L-serineL-serine is then metabolized by being dehydrated through either a L-serine dehydratase 2 or a L-serine dehydratase 1 resulting in the release of a water molecule, a hydrogen ion and a 2-aminoacrylic acid. The latter compound is an isomer of a 2-iminopropanoate which reacts spontaneously with a water molecule and a hydrogen ion resulting in the release of Ammonium and pyruvic acid. Pyruvic acid then interacts with a coenzyme A through a NAD driven pyruvate dehydrogenase complex resulting in the release of a NADH, a carbon dioxide and an acetyl-CoA."
What is the definition of Histidine Biosynthesis?,"Histidine biosynthesis starts with a product of PRPP biosynthesis pathway, phosphoribosyl pyrophosphate which interacts with a hydrogen ion through an ATP phosphoribosyltransferase resulting in an pyrophosphate and a phosphoribosyl-ATP. This compound interacts with water through a phosphoribosyl-AMP cyclohydrolase / phosphoribosyl-ATP pyrophosphatase resulting in the release of pyrophosphate, hydrogen ion and a phosphoribosyl-AMP. This enzyme proceeds to interact with phosphoribosyl-AMP and water resulting in a 1-(5'-Phosphoribosyl)-5-amino-4-imidazolecarboxamide. This compound is then isomerized by a N-(5'-phospho-L-ribosyl-formimino)-5-amino-1-(5'-phosphoribosyl)-4-imidazolecarboxamide isomerase resulting in a PhosphoribosylformiminoAICAR-phosphate. This compound reacts with L-glutamine through an imidazole glycerol phosphate synthase resulting in a L-glutamic acid, hydrogen ion, 5-aminoimidazole-4-carboxamide and a D-erythro-imidazole-glycerol-phosphate. This compound reacts with a imidazoleglycerol-phosphate dehydratase / histidinol-phosphatase, dehydrating the compound and resulting in a imidazole acetol-phosphate.This compound interacts with L-glutamic acid through a histidinol-phosphate aminotransferase, releasing oxoglutaric acid and L-histidinol-phosphate. The latter compound interacts with water and a imidazoleglycerol-phosphate dehydratase / histidinol-phosphatase resulting in L-histidinol and phosphate. L-histidinol interacts with a NAD-driven histidinol dehydrogenase resulting in a Histidinal. This in turn reacts with water in a NAD driven histidinal dehydrogenase resulting in L-Histidine.L-Histidine then represses ATP phosphoribosyltransferase, regulation its own biosynthesis."
What is the definition of Leucine Biosynthesis?,"Leucine biosynthesis involves a five-step conversion process starting with the valine precursor 2-keto-isovalerate interacting with acetyl-CoA and water through a 2-isopropylmalate synthase resulting in Coenzyme A, hydrogen Ion and 2-isopropylmalic acid. The latter compound reacts with isopropylmalate isomerase which dehydrates the compound resulting in a Isopropylmaleate. This compound reacts with water through a isopropylmalate isomerase resulting in 3-isopropylmalate. This compound interacts with a NAD-driven D-malate / 3-isopropylmalate dehydrogenase results in 2-isopropyl-3-oxosuccinate. This compound interacts spontaneously with hydrogen resulting in the release of carbon dioxide and ketoleucine. Ketoleucine interacts in a reversible reaction with L-glutamic acid through a branched-chain amino-acid aminotransferase resulting in Oxoglutaric acid and L-leucine. L-leucine can then be exported outside the cytoplasm through a transporter: L-amino acid efflux transporter. In the final step, ketoleucine can be catalyzed to form L-leucine by branched-chain amino-acid aminotransferase (IlvE) and tyrosine aminotransferase (TryB). L-Glutamic acid can also be transformed into oxoglutaric acid by these two enzymes. Tyrosine aminotransferase can be suppressed by lecuine, and inhibited by 2-keto-isovarlerate and its end product, tyrosine. 2-ketoisocaproate can not be introduced if 2-keto-isovarlerate inhibit TyrB and IlvE is absent."
What is the definition of Valine Biosynthesis?,"The pathway of valine biosynthesis starts with pyruvic acid interacting with a hydrogen ion through a acetolactate synthase / acetohydroxybutanoate synthase or a acetohydroxybutanoate synthase / acetolactate synthase resulting in the release of carbon dioxide and (S)-2-acetolactate. The latter compound then interacts with a hydrogen ion through an NADPH driven acetohydroxy acid isomeroreductase resulting in the release of a NADP and an (R) 2,3-dihydroxy-3-methylvalerate. The latter compound is then dehydrated by a dihydroxy acid dehydratase resulting in the release of water and isovaleric acid. Isovaleric acid interacts with an L-glutamic acid through a Valine Transaminase resulting in a oxoglutaric acid and an L-valine. L-valine is then transported into the periplasmic space through a L-valine efflux transporter."
What is the definition of Asparagine Biosynthesis?,"In E.coli, L-asparagine can be synthesized from L-aspartic acid by either utilizing asparagine synthetase B with L-glutamine or ammonia. Both reactions are driven by ATP. The reaction with ammonia utilize both asparagine synthetase B and aspartate-ammonia ligase. The role of asparagine is the constituent of protein for E.coli."
What is the definition of Methionine Biosynthesis?,"This pathway shows the biosynthesis of methionine, which is an energy-costly process. Lysine biosynthesis produces L-Aspartate-semialdehyde, which later on is catalyzed to L-homoserine by bifunctional aspartokinase (also named homoserine dehydrogenase) 1 and 2. Homoserine is then activated by O-succinylation to form O-succinyl-L-homoserine via homoserine O-succinyltransferase (metA). Combining with L-cysteine, O-succinyl-L-homoserine form L-cystathionine and succinic acid by cystathionine gamma-synthase (metB). Cleavage of L-cystathionine by cystathionine beta-lyase (metC) or Protein MalY(as ) generates two small molecules: homocysteine and 2-aminoprop-2-enoate. Methionine synthase(MetH) or 5-methyltetrahydropteroyltriglutamate--homocysteine methyltransferase(MetE) will catalyzehomocysteine to form the final product: methionine. In E.coli, MetH can only function with existence of cobalamin (Vitamin B12), which can be available in the guy; without cobalamin, MetE will not be repressed so that it will catalyze the methionine. Methionine can be transported out of cell (into periplasmic space) by leucine efflux transporter. "
What is the definition of Tryptophan Metabolism?,"The biosynthesis of L-tryptophan begins with L-glutamine interacting with a chorismate through a anthranilate synthase which results in a L-glutamic acid, a pyruvic acid, a hydrogen ion and a 2-aminobenzoic acid. The aminobenzoic acid interacts with a phosphoribosyl pyrophosphate through an anthranilate synthase component II resulting in a pyrophosphate and a N-(5-phosphoribosyl)-anthranilate. The latter compound is then metabolized by an indole-3-glycerol phosphate synthase / phosphoribosylanthranilate isomerase resulting in a 1-(o-carboxyphenylamino)-1-deoxyribulose 5'-phosphate. This compound then interacts with a hydrogen ion through a indole-3-glycerol phosphate synthase / phosphoribosylanthranilate isomerase resulting in the release of carbon dioxide, a water molecule and a  (1S,2R)-1-C-(indol-3-yl)glycerol 3-phosphate. The latter compound then interacts with a D-glyceraldehyde 3-phosphate and an Indole. The indole interacts with an L-serine through a tryptophan synthase, β subunit dimer resulting in a water molecule and an L-tryptophan.The metabolism of L-tryptophan starts with L-tryptophan being dehydrogenated by a tryptophanase / L-cysteine desulfhydrase resulting in the release of a hydrogen ion, an Indole and a 2-aminoacrylic acid. The latter compound is isomerized into a 2-iminopropanoate. This compound then interacts with a water molecule and a hydrogen ion  spontaneously resulting in the release of an Ammonium and a pyruvic acid. The pyruvic acid then interacts with a coenzyme A through a NAD driven pyruvate dehydrogenase complex resulting in the release of a NADH, a carbon dioxide and an Acetyl-CoA"
What is the definition of Chorismate Biosynthesis?,"Chorismate is an intermediate in tyrosine, phenylalanine and tryptophan synthesis and a precursor for folic acid, ubiquinone, enterochelin and menaquinone. Three enzymes catalyze the first step in chorismate biosynthesis. Synthesis may be reduced by feedback inhibition of tyrosine, phenylalanine and tryptophan to the enzymes. The biosynthesis of chorismate starts with D-Erythrose-4-phosphate getting transformed into 3-deoxy-D-arabino-heptulosonate-7-phosphate through a phospho-2-dehydro-3-deoxyheptonate aldolase. This is followed by a 3-dehydroquinate synthase converting the 3-deoxy-D-arabino-heptulosonate-7-phosphate into a 3-dehydroquinate which in turn is conveted to 3-dehydroshikimate through a 3-dehydroquinate dehydratase. A this point  3-dehydroshikimate can be turned into Shikimic acid through 2 different reactions involving Quinate/shikimate dehydrogenase and shikimate dehydrogenase 2. Shikimic acid is phosphorylated by Shikimate kinase 2 into shikimate 3-phosphate. Shikimate 3- phophate and  a phosphoenolpyruvic acid are then joined through a 3-phosphoshikimate 1-carboxyvinyltransferase to produce a 5-enoylpyruvyl-shikimate 3-phosphate while releasing a phosphate. This in turns produces our final product Chorismate through a chorismate synthase. "
What is the definition of Threonine Biosynthesis?,"The biosynthesis of threonine starts with oxalacetic acid interacting with an L-glutamic acid through an aspartate aminotransferase resulting in a oxoglutaric acid and an L-aspartic acid. The latter compound is then phosphorylated by an ATP driven Aspartate kinase resulting in an a release of an ADP and an L-aspartyl-4-phosphate. This compound interacts with a hydrogen ion through an NADPH driven aspartate semialdehyde dehydrogenase resulting in the release of a phosphate, an NADP and a L-aspartate-semialdehyde.The latter compound interacts with a hydrogen ion through a NADPH driven aspartate kinase / homoserine dehydrogenase resulting in the release of an NADP and a L-homoserine. L-homoserine is phosphorylated through an ATP driven homoserine kinase resulting in the release of an ADP, a hydrogen ion and a O-phosphohomoserine. The latter compound then interacts with a water molecule threonine synthase resulting in the release of a phosphate and an L-threonine. "
What is the definition of Isoleucine Biosynthesis?,"Isoleucine biosynthesis begins with L-threonine from the threonine biosynthesis pathway. L-threonine interacts with a threonine dehydratase biosynthetic releasing water, a hydrogen ion and (2Z)-2-aminobut-2-enoate. This compound is isomerized into a 2-iminobutanoate which interacts with water and a hydrogen ion spontaneously, resulting in the release of ammonium and 2-ketobutyric acid. This compound reacts with pyruvic acid and hydrogen ion through an acetohydroxybutanoate synthase / acetolactate synthase 2 resulting in carbon dioxide and (S)-2-Aceto-2-hydroxybutanoic acid. The latter compound is reduced by an NADPH driven acetohydroxy acid isomeroreductase releasing NADP and acetohydroxy acid isomeroreductase. The latter compound is dehydrated by a dihydroxy acid dehydratase resulting in  3-methyl-2-oxovaleric acid.This compound reacts in a reversible reaction with L-glutamic acid through a Branched-chain-amino-acid aminotransferase resulting in oxoglutaric acid and L-isoleucine.L-isoleucine can also be transported into  the cytoplasm through two different methods:  a branched chain amino acid ABC transporter or a branched chain amino acid transporter BrnQy."
What is the definition of Gluconeogenesis from L-Malic Acid?,"Gluconeogenesis from L-malic acid starts from the introduction of L-malic acid into cytoplasm either through a C4 dicarboxylate / orotate:H+ symporter or a dicarboxylate transporter (succinic acid antiporter). L-malic acid is then metabolized through 3 possible ways: NAD driven malate dehydrogenase resulting in oxalacetic acid, NADP driven malate dehydrogenase B resulting pyruvic acid or malate dehydrogenase, NAD-requiring resulting in pyruvic acid. Oxalacetic acid is processed by phosphoenolpyruvate carboxykinase (ATP driven) while pyruvic acid is processed by phosphoenolpyruvate synthetase resulting in phosphoenolpyruvic acid. This compound is dehydrated by enolase resulting in an 2-phosphoglyceric acid. This compound is then isomerized by 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 3-phosphoglyceric acid which is phosphorylated by an ATP driven phosphoglycerate kinase resulting in an glyceric acid 1,3-biphosphate. This compound undergoes an NADH driven glyceraldehyde 3-phosphate dehydrogenase reaction resulting in a D-Glyceraldehyde 3-phosphate which is first isomerized into dihydroxyacetone phosphate through an triosephosphate isomerase. D-glyceraldehyde 3-phosphate and Dihydroxyacetone phosphate react through a fructose biphosphate aldolase protein complex resulting in a fructose 1,6-biphosphate. This compound is metabolized by a fructose-1,6-bisphosphatase resulting in a Beta-D-fructofuranose 6-phosphate which is then isomerized into a Beta-D-glucose 6-phosphate through a glucose-6-phosphate isomerase. "
What is the definition of Galactitol and Galactonate Degradation?,"Escherichia coli can solely use D-galactonate as a carbon and energy source. The initial step, after the transport of galactonic acid into the cell is the dehydration of D-galactonate to 2-dehydro-3-deoxy-D-galactonate by D-galactonate dehydratase. Subsequent phosphorylation by 2-dehydro-3-deoxygalactonate kinase and aldol cleavage by 2-oxo-3-deoxygalactonate 6-phosphate aldolase produces pyruvate and D-glyceraldehyde-3-phosphate, which enter central metabolism. Galactitol can also be utilized by E. coli K-12 as the sole source of carbon and energy. Each enters the cell via a specific phosphotransferase system, so the first intracellular species is  D-galactitol-1-phosphate or D-galactitol-6-phosphate, which are identical. This sugar alcohol phosphate becomes the substrate for a dehydrogenase that oxidizes its 2-alcohol group to a keto group. Galactitol-1-phosphate is dehydrogenated to tagatose-6-phosphate which is then acted on by a kinase and an aldose and eventually is converted to glycolysis intermediates. "
What is the definition of Galactose Metabolism?,"Galactose can be synthesized through two pathways: melibiose degradation involving an alpha galactosidase and lactose degradation involving a beta galactosidase. Melibiose is first transported inside the cell through the melibiose:Li+/Na+/H+ symporter. Once inside the cell, melibiose is degraded through alpha galactosidase  into an alpha-D-galactose and a beta-D-glucose. The beta-D-glucose is phosphorylated by a glucokinase to produce a beta-D-glucose-6-phosphate which can spontaneously be turned into a alpha D glucose 6 phosphate. This alpha D-glucose-6-phosphate is metabolized into a glucose -1-phosphate through a phosphoglucomutase-1. The glucose -1-phosphate is transformed into a uridine diphosphate glucose through UTP--glucose-1-phosphate uridylyltransferase. The product, uridine diphosphate glucose, can undergo a reversible reaction in which it can be turned into uridine diphosphategalactose through an UDP-glucose 4-epimerase.Galactose can also be produced by lactose degradation involving a lactose permease to uptake lactose from the environment and a beta-galactosidase to turn lactose into Beta-D-galactose. Beta-D-galactose can also be uptaken from the environment through a galactose proton symporter.Galactose is degraded through the following process:Beta-D-galactose is introduced into the cytoplasm through a galactose proton symporter, or it can be synthesized from an alpha lactose that is introduced into the cytoplasm through a lactose permease. Alpha lactose interacts with water through a beta-galactosidase resulting in a beta-D-glucose and beta-D-galactose. Beta-D-galactose is isomerized into D-galactose. D-Galactose undergoes phosphorylation through a galactokinase, hence producing galactose 1 phosphate. On the other side of the pathway, a gluose-1-phosphate (product of the interaction of alpha-D-glucose 6-phosphate with a phosphoglucomutase resulting in a alpha-D-glucose-1-phosphate, an isomer of Glucose 1-phosphate, or an isomer of Beta-D-glucose 1-phosphate) interacts with UTP and a hydrogen ion in order to produce a uridine diphosphate glucose. This is followed by the interaction of galactose-1-phosphate with an established amount of uridine diphosphate glucose through a galactose-1-phosphate uridylyltransferase, which in turn output a glucose-1-phosphate and a uridine diphosphate galactose. The glucose -1-phosphate is transformed into a uridine diphosphate glucose through UTP--glucose-1-phosphate uridylyltransferase. The product, uridine diphosphate glucose, can undergo a reversible reaction in which it can be turned into uridine diphosphategalactose through an  UDP-glucose 4-epimerase, and so the cycle can keep going as long as more lactose or galactose is imported into the cell"
What is the definition of Mannose Metabolism?,"Escherichia coli can utilize D-mannose for its sole carbon and energy source. Alpha-D-mannose is introduced into the cytoplasm through a mannose PTS permease. A phosphotransferase system (PTS) takes up mannose producing D-mannose-6-phosphate which is then converted to D-fructose-6-phosphate via an isomerase. D-fructose-6-phosphate is an intermediate of glycolysis and can enter the pathways of metabolism.  The first two enzymes in the pathway catalyze isomerizations that interconvert phosphorylated aldohexoses (β-D-glucose-6-phosphate, D-mannose-6-phosphate) and phosphorylated ketohexoses (D-fructose-6-phosphate). The reaction catalyzed by mannose-6-phosphate isomerase that produces D-mannose-6-phosphate is the first committed step in the biosynthesis of the activated mannose donor GDP-α-D-mannose. D-mannose-6-phosphate is then converted to GDP-D-mannose by the interaction of phosphomannomutase and mannose-1-phosphate guanylyltransferase. GDP-D-mannose produces GDP-L-fucose beginning with the dehydration to GDP-4-dehydro-6-deoxy-D-mannose. GDP-fucose is synthesized by a two step epimerase and reductase of GDP-4-dehydro-6-deoxy-D-mannose. L-fucose then enters the colanic acid building blocks biosynthesis pathway."
What is the definition of D-Allulose Degradation?,"D-allose can be used as source of carbon for E.coli. D-allose is imported into E.coli by D-allose ABC transporter without phosphorylation. Allose-6-phosphate isomerase and allulose-6-phosphate 3-epimerase catalyze the remaining reactions resulting in D-allulose 6 phosphate and Beta-D-fructofuranose 6-phosphate respectively. Once Beta D fructofuranose 6-phosphate is synthesized, it goes into the glycolysis and pyruvatedehydrogenase pathway."
What is the definition of Fucose and Rhamnose Degradation?,"In E. coli, L-fucose and L-rhamnose are metabolized through parallel pathways. The pathways converge after their corresponding aldolase reactions yielding the same products: lactaldehye. Proton symporter can facilitate the import of alpha-L-rhamnopyranose, methylpentose and beta-L-rhamnopyranose into cell for further metabolism, which allow E.coli to grow with carbon and energy. For alpha-L-rhamnopyranose, it is isomerized by a l-rhamnose mutarotase resulting in a beta-L-rhamnopyranose which is then isomerized into a keto-L-rhamnulose by a l-rhamnose isomerase. The keto-L-rhamnulose spontaneously changes into a L-rhamnulofuranose which is phosphorylated by a rhamnulokinase resulting in a L-rhamnulose 1-phosphate. This compound reacts with a rhamnulose-1-phosphate aldolase resulting in a dihydroxyacetone phosphate and a lactaldehyde. For beta-L-rhamnopyranose, it is isomerized by a L-fucose mutarotase resulting in a alpha-L-fucopyranose. This compound is then isomerized by an L-fucose isomerase resulting in a L-fuculose which in turn gets phosphorylated into an L-fuculose 1-phosphate through an L-fuculokinase. The compound L-fuculose 1-phosphate reacts with an L-fuculose phosphate aldolase through a dihydroxyacetone phosphate and a lactaldehyde. Two pathways can both be used for degrading L-lactaldehyde, which the aerobic pathway facilitates the conversion  from L-lactic acid to pyruvic acid via L-lactate dehydrogenase, and the anaerobic pathway facilitates conversion from lactaldehyde to propane-1,2-diol via lactaldehyde reductase. Under aerobic conditions, L-lactaldehyde is oxidized in two steps to pyruvate, thereby channeling all the carbons from fucose or rhamnose into central metabolic pathways. Under anaerobic conditions, L-lactaldehyde is reduced to L-1,2-propanediol, which is secreted into the environment."
What is the definition of Glycolate and Glyoxylate Degradation?,"Glycolic acid is introduced into the cytoplasm through either a glycolate / lactate:H+ symporter or a acetate / glycolate transporter. Once inside, glycolic acid reacts with an oxidized electron-transfer flavoprotein through a glycolate oxidase resulting in a reduced acceptor and glyoxylic acid. Glyoxylic acid can also be obtained from the introduction of glyoxylic acid. It can also be obtained from the metabolism of (S)-allantoin.S-allantoin is introduced into the cytoplasm through a purine and pyrimidine transporter(allantoin specific). Once inside, the compound reacts with water through a allantoinase resulting in hydrogen ion and allantoic acid. Allantoic acid then reacts with water and hydrogen ion through a allantoate amidohydrolase resulting in a carbon dioxide, ammonium and S-ureidoglycine. The latter compound reacts with water through a S-ureidoglycine aminohydrolase resulting in ammonium and S-ureidoglycolic acid which in turn reacts with a Ureidoglycolate lyase resulting in urea and glyoxylic acid. Glyoxylic acid can either be metabolized into L-malic acid by a reaction with acetyl-CoA and Water through a malate synthase G which also releases hydrogen ion and Coenzyme A. L-malic acid is then incorporated into the TCA cycle.Glyoxylic acid can also be metabolized by glyoxylate carboligase, releasing a carbon dioxide and tartronate semialdehyde. The latter compound is then reduced by an NADH driven tartronate semialdehyde reductase 2 resulting in glyceric acid. Glyceric acid is phosphorylated by a glycerate kinase 2 resulting in a 3-phosphoglyceric acid. This compound is then integrated into various other pathways: cysteine biosynthesis, serine biosynthesis and glycolysis and pyruvate dehydrogenase."
What is the definition of Pantothenate and CoA Biosynthesis?,"The CoA biosynthesis requires compounds from two other pathways: aspartate metabolism and valine biosynthesis. It requires a Beta-Alanine and R-pantoate. The compound (R)-pantoate is generated in two reactions, as shown by the interaction of alpha-ketoisovaleric acid, 5,10 methylene-THF and water through a 3-methyl-2-oxobutanoate hydroxymethyltransferase resulting in a tetrahydrofolic acid and a 2-dehydropantoate. This compound interacts with hydrogen through a NADPH driven acetohydroxy acid isomeroreductase resulting in the release of NADP and R-pantoate. On the other hand L-aspartic acid interacts with a hydrogen ion and gets decarboxylated through an Aspartate 1- decarboxylase resulting in a carbon dioxide and a Beta-alanine. Beta-alanine and R-pantoate interact with an ATP driven pantothenate synthetase resulting in pyrophosphate, AMP, hydrogen ion and pantothenic acid. Pantothenic acid is phosphorylated through a ATP-driven pantothenate kinase resulting in a ADP, a hydrogen ion and D-4'-Phosphopantothenate. This compound interacts with a CTP and a L-cysteine resulting in a fused 4'phosphopantothenoylcysteine decarboxylase and phosphopantothenoylcysteine synthetase resulting in a hydrogen ion, a pyrophosphate, a CMP and 4-phosphopantothenoylcysteine. The latter compound interacts with a hydrogen ion through a fused 4'-phosphopantothenoylcysteine decarboxylase and phosphopantothenoylcysteine synthetase resulting in a carbon dioxide release and a 4-phosphopantetheine. This compound interacts with an ATP, hydrogen ion and an phosphopantetheine adenylyltransferase resulting in a release of pyrophosphate, and dephospho-CoA. Dephospho-CoA reacts with an ATP driven dephospho-CoA kinase resulting in a ADP , a hydrogen ion and a Coenzyme A. Dephospho-CoA also reacts with 2-(5''-triphosphoribosyl)-3'-dephosphocoenzyme-A synthase (citG) to form both adenine and 2'-(5-Triphosphoribosyl)-3'-dephospho-CoA. In this pathway, all enzymes are essential for the cell growth. Biosynthetic pathway for producing CoA is same for most organisms (with exception of differences in the functionality of involved enzymes). In plants, every step is catalyzed by monofunctional enzymes instead of biofunctional enzymes."
What is the definition of NAD Biosynthesis?,"Nicotinamide adenine dinucleotide (NAD) can be biosynthesized from L-aspartic acid.This amino acid reacts with oxygen through an L-aspartate oxidase resulting in a hydrogen ion, hydrogen peroxide and an iminoaspartic acid. The latter compound interacts with dihydroxyacetone phosphate through a quinolinate synthase A, resulting in a phosphate, water, and a quinolic acid. Quinolic acid interacts with phosphoribosyl pyrophosphate and hydrogen ion through a quinolinate phosphoribosyltransferase resulting in pyrophosphate, carbon dioxide and nicotinate beta-D-ribonucleotide. This last compound is adenylated through an ATP driven nicotinate-mononucleotide adenylyltransferase releasing a pyrophosphate and resulting in a nicotinic acid adenine dinucleotide.Nicotinic acid adenine dinucleotide is processed through an NAD synthetase, NH3-dependent in two different manners.In the first case, Nicotinic acid adenine dinucleotide interacts with ATP, L-glutamine and water through the enzyme and results in hydrogen ion, AMP, pyrophosphate, L-glutamic acid and NAD.In the second case, Nicotinic acid adenine dinucleotide interacts with ATP and ammonium through the enzyme resulting in a pyrophosphate, AMP, hydrogen ion and NAD.NAD then proceeds to regulate its own pathway by repressing L-aspartate oxidase.As a general rule, most prokaryotes utilize the aspartate de novo pathway, in which the nicotinate moiety of NAD is synthesized from aspartate , while in eukaryotes, the de novo pathway starts with tryptophan."
What is the definition of NAD Salvage?,"NAD molecules have a relatively short half-life. NAD can be degraded by enzyme, and the degraded NAD molecule can be recouped by NAD salvage cycles. NAD salvage cycles can be used for recycling degraded NAD products such as nicotinamide and nicotinamide D-ribonucleotide. NAD salvage cycles can also be used for absorption of exogenous NAD+. NAD reacts spontaneously with water resulting in the release of hydrogen ion, AMP and beta-nicotinamide D-ribonucleotide. This enzyme can either interact spontaneously with water resulting in the release of D-ribofuranose 5-phosphate, hydrogen ion and Nacinamide. On the other hand beta-nicotinamide D-ribonucleotide can also react with water through NMN amidohydrolase resulting in ammonium, and Nicotinate beta-D-ribonucleotide. Also it can interact with water spontaneously resulting in the release of phosphate resulting in a Nicotinamide riboside. Niacinamide interacts with water through a nicotinamidase resulting in a release of ammonium and nicotinic acid. This compound interacts with water and phosphoribosyl pyrophosphate through an ATP driven nicotinate phosphoribosyltransferase resulting in the release of ADP, pyrophosphate and phosphate and nicotinate beta-D-ribonucleotide. Nicotinamide riboside interacts with an ATP driven NadR DNA-binding transcriptional repressor and NMN adenylyltransferase (Escherichia coli) resulting in a ADP, hydrogen ion and beta-nicotinamide D-ribonucleotide. This compound interacts with ATP and hydrogen ion through NadR DNA-binding transcriptional repressor and NMN adenylyltransferase resulting in pyrophosphate and NAD. Nicotinate beta-D-ribonucleotide is adenylated through the interaction with ATP and a hydrogen ion through a nicotinate-mononucleotide adenylyltransferase resulting in pyrophosphate and Nicotinic acid adenine dinucleotide. Nicotinic acid adenine dinucleotide interacts with L-glutamine and water through an ATP driven NAD synthetase, NH3-dependent resulting in AMP, pyrophosphate, hydrogen ion, L-glutamic acid and NAD. "
What is the definition of Lipopolysaccharide Biosynthesis?,"E. coli lipid A is synthesized on the cytoplasmic surface of the inner membrane. The pathway can start from the fructose 6-phosphate that is either produced in the glycolysis and pyruvate dehydrogenase or be obtained from the interaction with D-fructose interacting with a mannose PTS permease. Fructose 6-phosphate interacts with L-glutamine through a D-fructose-6-phosphate aminotransferase resulting into a L-glutamic acid and a glucosamine 6-phosphate. The latter compound is isomerized through a phosphoglucosamine mutase resulting a glucosamine 1-phosphate. This compound is acetylated, interacting with acetyl-CoA through a bifunctional protein glmU resulting in a Coenzyme A, hydrogen ion and N-acetyl-glucosamine 1-phosphate. This compound interact with UTP and hydrogen ion through the bifunctional protein glmU resulting in a pyrophosphate and a UDP-N-acetylglucosamine. This compound interacts with (3R)-3-hydroxymyristoyl-[acp] through an UDP-N-acetylglucosamine acyltransferase resulting in a holo-[acp] and a UDP-3-O[(3R)-3-hydroxymyristoyl]-N-acetyl-alpha-D-glucosamine. This compound interacts with water through UDP-3-O-acyl-N-acetylglucosamine deacetylase resulting in an acetic acid and UDP-3-O-(3-hydroxymyristoyl)-α-D-glucosamine. The latter compound interacts with (3R)-3-hydroxymyristoyl-[acp] through UDP-3-O-(R-3-hydroxymyristoyl)-glucosamine N-acyltransferase releasing a hydrogen ion, a holo-acp and UDP-2-N,3-O-bis[(3R)-3-hydroxytetradecanoyl]-α-D-glucosamine. The latter compound is hydrolase by interacting with water and a UDP-2,3-diacylglucosamine hydrolase resulting in UMP, hydrogen ion and  2,3-bis[(3R)-3-hydroxymyristoyl]-α-D-glucosaminyl 1-phosphate. This last compound then interacts with a UDP-2-N,3-O-bis[(3R)-3-hydroxytetradecanoyl]-α-D-glucosamine through a lipid A disaccharide synthase resulting in a release of UDP, hydrogen ion and a lipid A disaccharide.  The lipid A disaccharide is phosphorylated by an ATP mediated tetraacyldisaccharide 4'-kinase resulting in the release of hydrogen ion and lipid IVA.  A D-ribulose 5-phosphate is isomerized with D-arabinose 5-phosphate isomerase 2  to result in a D-arabinose 5-phosphate. This compounds interacts with water and phosphoenolpyruvic acid through a 3-deoxy-D-manno-octulosonate 8-phosphate synthase resulting in the release of phosphate and  3-deoxy-D-manno-octulosonate 8-phosphate. This compound interacts with water through a 3-deoxy-D-manno-octulosonate 8-phosphate phosphatase thus releasing a phosphate and a 3-deoxy-D-manno-octulosonate. The latter compound interacts with CTP through a 3-deoxy-D-manno-octulosonate cytidylyltransferase resulting in a pyrophosphate and CMP-3-deoxy-α-D-manno-octulosonate.CMP-3-deoxy-α-D-manno-octulosonate and lipid IVA interact with each other through a KDO transferase resulting in CMP, hydrogen ion and alpha-Kdo-(2-->6)-lipid IVA. The latter compound reacts with CMP-3-deoxy-α-D-manno-octulosonate through a KDO transferase resulting in a CMP, hydrogen ion, and a a-Kdo-(2->4)-a-Kdo-(2->6)-lipid IVA. The latter compound can either react with a palmitoleoyl-acp through a palmitoleoyl acyltransferase resulting in the release of a holo-acyl carriere protein and a Kdo2-palmitoleoyl-lipid IVa which in turn reacts with a myristoyl-acp through a myristoyl-acp dependent acyltransferase resulting in a release of a holo-acp and a Kdo2-lipid A, cold adapted, or it can interact with a dodecanoyl-[acp] lauroyl acyltransferase resulting in a holo-[acp] and a (KDO)2-(lauroyl)-lipid IVA. The latter compound reacts with a myristoyl-[acp] through a myristoyl-acyl carrier protein (ACP)-dependent acyltransferase resulting in a holo-[acp], (KDO)2-lipid A. The latter compound reacts with ADP-L-glycero-beta-D-manno-heptose through ADP-heptose:LPS heptosyltransferase I resulting hydrogen ion, ADP, heptosyl-KDO2-lipid A. The latter compound interacts with ADP-L-glycero-beta-D-manno-heptose through ADP-heptose:LPS heptosyltransferase II resulting in ADP, hydrogen ion and (heptosyl)2-Kdo2-lipid A. The latter compound UDP-glucose interacts with (heptosyl)2-Kdo2-lipid A resulting in UDP, hydrogen ion and glucosyl-(heptosyl)2-Kdo2-lipid A. Glucosyl-(heptosyl)2-Kdo2-lipid A (Escherichia coli) is phosphorylated through an ATP-mediated lipopolysaccharide core heptose (I) kinase resulting in ADP, hydrogen ion and glucosyl-(heptosyl)2-Kdo2-lipid A-phosphate.The latter compound interacts with ADP-L-glycero-beta-D-manno-heptose through a lipopolysaccharide core heptosyl transferase III resulting in ADP, hydrogen ion, and  glucosyl-(heptosyl)3-Kdo2-lipid A-phosphate. The latter compound is phosphorylated through an ATP-driven lipopolysaccharide core heptose (II) kinase resulting in ADP, hydrogen ion and glucosyl-(heptosyl)3-Kdo2-lipid A-bisphosphate. The latter compound interacts with UDP-alpha-D-galactose through a UDP-D-galactose:(glucosyl)lipopolysaccharide-1,6-D-galactosyltransferase resulting in a UDP, a hydrogen ion and a galactosyl-glucosyl-(heptosyl)3-Kdo2-lipid A-bisphosphate. The latter compound interacts with UDP-glucose through a (glucosyl)LPS α-1,3-glucosyltransferase resulting in a hydrogen ion, a UDP and galactosyl-(glucosyl)2-(heptosyl)3-Kdo2-lipid A-bisphosphate. This compound then interacts with UDP-glucose through a UDP-glucose:(glucosyl)LPS α-1,2-glucosyltransferase resulting in UDP, a hydrogen ion and galactosyl-(glucosyl)3-(heptosyl)3-Kdo2-lipid A-bisphosphate. This compound then interacts with ADP-L-glycero-beta-D-manno-heptose  through a lipopolysaccharide core biosynthesis; heptosyl transferase IV; probably hexose transferase resulting in a Lipid A-core.A lipid A-core is then exported into the periplasmic space by a lipopolysaccharide ABC transporter.The lipid A-core is then flipped to the outer surface of the inner membrane by the ATP-binding cassette (ABC) transporter, MsbA. An additional integral membrane protein, YhjD, has recently been implicated in LPS export across the IM. The smallest LPS derivative that supports viability in E. coli is lipid IVA. However, it requires mutations in either MsbA or YhjD, to suppress the normally lethal consequence of an incomplete lipid A . Recent studies with deletion mutants implicate the periplasmic protein LptA, the cytosolic protein LptB, and the IM proteins LptC, LptF, and LptG in the subsequent transport of nascent LPS to the outer membrane (OM), where the LptD/LptE complex flips LPS to the outer surface. "
What is the definition of Glutathione Metabolism?,"The biosynthesis of glutathione starts with the introduction of L-glutamic acid through either  a glutamate:sodium symporter, glutamate / aspartate : H+ symporter GltP or a glutamate / aspartate ABC transporter. Once in the cytoplasm, L-glutamice acid reacts with L-cysteine through an ATP glutamate-cysteine ligase resulting in gamma-glutamylcysteine. This compound reacts which Glycine through an ATP driven glutathione synthetase thus catabolizing Glutathione.This compound is metabolized through a spontaneous reaction with an oxidized glutaredoxin resulting in a reduced glutaredoxin and an oxidized glutathione. This compound is reduced by a NADPH glutathione reductase resulting in a glutathione. Glutathione can then be degraded into various different glutathione containg compounds by reacting with a napthalene or Bromobenzene-2,3-oxide through a glutathione S-transferase"
What is the definition of Hexuronide and Hexuronate Degradation?,"Beta-D-glucuronosides, D-glucuronate and D-fructuronate can be used as source of carbon for E.coli. They are imported into E.coli's periplasmic space by membrane-associated protein (UidC/gusC), and are further imported into cytoplasm by hydrogen symporter. Beta-glucuronides undergoes hydrolysis by beta-D-glucuronidase to form D-glucuronate. D-glucuronate is isomerized by D-glucuronate isomerase to form D-fructuronate. D-fructuronate is further reduced to D-mannonate by D-mannonate oxidoreductase. D-mannonate dehydratase dehydrated to yield 2-dehydro-3-deoxy-D-gluconate. At this point, a common enzyme, 2-keto-3-deoxygluconokinase, phosphorylates 2-dehydro-3-deoxy-D-gluconate to yield 2-dehydro-3-deoxy-D-gluconate-6-phosphate. This product is then process by KHG/KDPG aldolase which in turn produces D-Glyceraldehyde 3-phosphate and Pyruvic Acid which then go into their respective sub pathways: glycolysis and pyruvate dehydrogenase. The pathway can also start from 3 other points: a hydrogen ion symporter (gluconate/fructuronate transporter GntP) of D-fructuronate, a hydrogen ion symporter (Hexuronate transporter) of aldehydo-D-galacturonate that spontaneously turns into D-tagaturonate. This compound can also be obtained by the reaction of aldehydo-L-galactonate with a NAD dependent l-galactonate oxidoreductase resulting in the release of NADH, hydrogen ion. Tagaturonate then undergoes an NADH-dependent reduction to D-altronate through an altronate oxidoreductase. D-altronate undergoes dehydration to yield 2-dehydro-3-deoxy-D-gluconate, the third and last point where the reaction can start from a hydrogen symporter of a 2-dehydro-3-deoy-D-gluconate."
What is the definition of Quorum Sensing?,"Bacterial Autoinducer 2 (AI-2) mediates the quorum sensing 2 system. AI-2 is catalyzed by the luxS enzyme. This enzyme is found in E.coli and S.typhimurium. In E. coli and most pathogenic bacteria that form AI-2 are spontaneous transformations that include cyclization to (2R,4S)-2-methyl-2,4-dihydroxydihydrofuran-3-one and hydration to the final autoinducer (2R,4S)-2-methyl-2,3,3,4-tetrahydroxytetrahydrofuran. This product is released from the cell through the AI-2 transporter (tqsA).As the level of AI-2 increases, other cells detect it and import it through the autoinducer-2 ABC transporter (lsrACDB). AI-2 is then degraded in the cells by phosphorylating the AI-2 which is then isomerized to P-HPD which follows by the transfer of and acetyl group to coenzyme A and releases dihydroxyacetone phosphate"
What is the definition of S-Adenosyl-L-Methionine Biosynthesis?,"S-adenosyl-L-methionine biosynthesis(SAM) is synthesized in the cytosol of the cell from L-methionine and ATP. This reaction is catalyzed by methionine adenosyltransferase. L methione is taken up from the environment through a complex reaction coupled transport and then proceeds too synthesize the s adenosylmethionine through a adenosylmethionine synthase. The S-adenosylmethionine then interacts with a hydrogen ion through a adenosylmethionine decarboxylase resulting in a carbon dioxide and a S-adenosyl 3-methioninamine.This compound interacts with a putrescine through a spermidine synthase resulting in a spermidine, a hydrogen ion and a S-methyl-5'-thioadenosine. The latter compound is degraded by interacting with a water molecule through a 5' methylthioadenosine nucleosidase resulting in a adenine and a S-methylthioribose which is then release into the environment"
What is the definition of Galactose Degradation/Leloir Pathway?,"The degradation of galactose, also known as Leloir pathway, requires 3 main enzymes once Beta-D-galactose has been converted to galactose through an Aldose-1-epimerase. These are:  galactokinase , galactose-1-phosphate uridylyltransferase and UDP-glucose 4-epimerase. Beta-D-galactose can be uptaken from the environment through a galactose proton symporter. It can also be produced by lactose degradation involving a lactose permease to uptake lactose from the environment and a beta-galactosidase to turn lactose into Beta-D-galactose. Galactose is degraded through the following process:Beta-D-galactose is introduced into the cytoplasm through a galactose proton symporter, or it can be synthesized from an alpha lactose that is introduced into the cytoplasm through a lactose permease. Alpha lactose interacts with water through a beta-galactosidase resulting in a beta-D-glucose and beta-D-galactose. Beta-D-galactose is isomerized into D-galactose. D-Galactose undergoes phosphorylation through a galactokinase, hence producing galactose 1 phosphate. On the other side of the pathway, a gluose-1-phosphate (product of the interaction of alpha-D-glucose 6-phosphate with a phosphoglucomutase resulting in a alpha-D-glucose-1-phosphate, an isomer of Glucose 1-phosphate, or an isomer of Beta-D-glucose 1-phosphate) interacts with UTP and a hydrogen ion in order to produce a uridine diphosphate glucose. This is followed by the interaction of galactose-1-phosphate with an established amount of uridine diphosphate glucose through a galactose-1-phosphate uridylyltransferase, which in turn output a glucose-1-phosphate and a uridine diphosphate galactose. The glucose -1-phosphate is transformed into a uridine diphosphate glucose through UTP--glucose-1-phosphate uridylyltransferase. The product, uridine diphosphate glucose, can undergo a reversible reaction in which it can be turned into uridine diphosphategalactose through an  UDP-glucose 4-epimerase, and so the cycle can keep going as long as more lactose or galactose is imported into the cell."
What is the definition of Amino Sugar and Nucleotide Sugar Metabolism I?,"The synthesis of amino sugars and nucleotide sugars  starts with the phosphorylation of N-Acetylmuramic acid (MurNac) through its transport from the periplasmic space to the cytoplasm. Once in the cytoplasm, MurNac and water undergo a reversible reaction through a N-acetylmuramic acid 6-phosphate etherase, producing a D-lactic acid and N-Acetyl-D-Glucosamine 6-phosphate. This latter compound can also be introduced into the cytoplasm through a phosphorylating PTS permase in the inner membrane that allows for the transport of N-Acetyl-D-glucosamine from the periplasmic space.  N-Acetyl-D-Glucosamine 6-phosphate can also be obtained from chitin dependent reactions. Chitin is hydrated through a bifunctional chitinase to produce chitobiose. This in turn gets hydrated by a beta-hexosaminidase to produce N-acetyl-D-glucosamine. The latter undergoes an atp dependent phosphorylation leading to the production of N-Acetyl-D-Glucosamine 6-phosphate. N-Acetyl-D-Glucosamine 6-phosphate is then be deacetylated in order to produce Glucosamine 6-phosphate through a N-acetylglucosamine-6-phosphate deacetylase. This compound can either be isomerized  or deaminated into Beta-D-fructofuranose 6-phosphate through a glucosamine-fructose-6-phosphate aminotransferase and a glucosamine-6-phosphate deaminase respectively. Glucosamine 6-phosphate undergoes a reversible reaction to glucosamine 1 phosphate through a phosphoglucosamine mutase. This compound is then acetylated through a bifunctional protein glmU to produce a N-Acetyl glucosamine 1-phosphate. N-Acetyl glucosamine 1-phosphate enters the nucleotide sugar synthesis by reacting with UTP and hydrogen ion through a bifunctional protein glmU releasing pyrophosphate and a Uridine diphosphate-N-acetylglucosamine.This compound can either be isomerized into a  UDP-N-acetyl-D-mannosamine or undergo a reaction with phosphoenolpyruvic acid through UDP-N-acetylglucosamine 1-carboxyvinyltransferase releasing a phosphate and a UDP-N-Acetyl-alpha-D-glucosamine-enolpyruvate.UDP-N-acetyl-D-mannosamine undergoes a NAD dependent dehydrogenation  through a UDP-N-acetyl-D-mannosamine dehydrogenase, releasing NADH, a hydrogen ion and a UDP-N-Acetyl-alpha-D-mannosaminuronate, This compound is then used in the production of enterobacterial common antigens. UDP-N-Acetyl-alpha-D-glucosamine-enolpyruvate is reduced through a NADPH dependent UDP-N-acetylenolpyruvoylglucosamine reductase, releasing a NADP and a UDP-N-acetyl-alpha-D-muramate. This compound is involved in the D-glutamine and D-glutamate metabolism."
What is the definition of beta-Alanine Metabolism?,"Beta-Alanine metabolism starts with a product of aspartate metabolism. Aspartate is decarboxylated by aspartate 1-decarboxylase, releasing carbon dioxide and beta-alanine. Beta-Alanine is then metabolized through a pantothenate synthetase resulting in pantothenic acid. Pantothenic acid then undergoes phosphorylation through an ATP-driven pantothenate kinase, resulting in D-4-phosphopantothenate. Pantothenate, vitamin B5, is a precursor for synthesis of 4'-phosphopantetheine moiety of coenzyme A and acyl carrier protein. Plants and microorganisms can synthesize pantothenate de novo, but animals must obtain it from diet. Enzymes of beta-alanine metabolism are targets for anti-microbial drugs. "
What is the definition of Fatty Acid Biosynthesis?,"The fatty acid biosynthesis starts from acetyl-CoA reacting either with a holo-[acp] through a 3-oxoacyl-[acp]  synthase 3 resulting in an acetyl-[acp] or react with hydrogen carbonate through an ATP driven acetyl-CoA carboxylase resulting in a malonyl-CoA.Malonyl-CoA reacts with a holo-acp] through a malonyl-CoA-ACP transacylase resulting in a malonyl-[acp]. This compound can react with a KASI protein resulting in an acetyl-[acp]. A malonyl-[acp] can also react with an acetyl-[acp] through KASI and KASII or with acetyl-CoA through a beta-ketoacyl-ACP synthase to produce an acetoacetyl-[acp]. An acetoacetyl-[acp] is also known as a 3-oxoacyl-[acp].A 3-oxoacyl-[acp] is reduced through a NDPH mediated 3-oxoacyl-[acp] reductase resulting in a (3R)-3-hydroxyacyl-[acp] (R3 hydroxydecanoyl-[acp]) which can either join the fatty acid metabolism, be dehydrated by an 3R-hydroxymyristoyl-[acp] dehydratase to produce a trans-2-enoyl-[acp] or  be dehydrated by a hydroxydecanoyl-[acp] to produce a trans-delta2 decenoyl-[acp].Trans-2-enoyl-[acp] is reduced by a NADH driven enoyl-[acp] reductase resulting in a 2,3,4-saturated fatty acyl-[acp]. This product then reacts with malonyl-[acp] through KASI and KASII resulting in a holo-acyl carrier protein and a 3- oxoacyl-[acp].Trans-delta2 decenoyl-[acp] reacts with a 3-hydroxydecanoyl-[acp] dehydrase producing a cis-delta 3-decenoyl-ACP. This product then reacts with KASI to produce a 3-oxo-cis-delta5-dodecenoyl-[acp], which in turn is reduced by a NADPH driven 3-oxoacyl-[acp] resulting in a 3R-hydroxy cis delta5-dodecenoyl-acp. This product is dehydrated by a (3R)-hydroxymyristoyl-[acp] dehydratase resulting in a trans-delta 3- cis-delta 5-dodecenoyl-[acp] which in turn is reduced by a NADH driven enoyl-[acp] reductase resulting in a cis-delta5-dodecenoyl-acp which goes into fatty acid metabolism"
What is the definition of Peptidoglycan Biosynthesis I?,"Peptidoglycan is a net-like polymer which surrounds the cytoplasmic membrane of most bacteria and functions to maintain cell shape and prevent rupture due to the internal turgor.In E. coli K-12, the peptidoglycan consists of glycan strands of alternating subunits of N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc) which are cross-linked by short peptides. The pathway for constructing this net involves two cell compartments: cytoplasm and periplasmic space. The pathway starts with a beta-D-fructofuranose going through a mannose  PTS permease, phosphorylating the compund and producing a beta-D-fructofuranose 6 phosphate. This compound can be obtained from the glycolysis and pyruvate dehydrogenase or from an isomerization reaction of Beta-D-glucose 6-phosphate through a glucose-6-phosphate isomerase.The compound Beta-D-fructofuranose 6 phosphate and L-Glutamine react with a glucosamine fructose-6-phosphate aminotransferase, thus producing a glucosamine 6-phosphate  and a l-glutamic acid. The glucosamine 6-phosphate interacts with phosphoglucosamine mutase in a reversible reaction producing glucosamine-1P. Glucosamine-1p and acetyl coa undergo acetylation throuhg a bifunctional protein glmU releasing Coa and a hydrogen ion and producing a N-acetyl-glucosamine 1-phosphate. Glmu, being a bifunctional protein, follows catalyze the interaction of N-acetyl-glucosamine 1-phosphate, hydrogen ion and UTP into UDP-N-acetylglucosamine and pyrophosphate. UDP-N-acetylglucosamine then interacts with phosphoenolpyruvic acid and a UDP-N acetylglucosamine 1- carboxyvinyltransferase realeasing a phosphate and the compound UDP-N-acetyl-alpha-D-glucosamine-enolpyruvate. This compound undergoes a NADPH dependent reduction producing a UDP-N-acetyl-alpha-D-muramate through a UDP-N-acetylenolpyruvoylglucosamine reductase. UDP-N-acetyl-alpha-D-muramate and L-alanine react in an ATP-mediated ligation through a UDP-N-acetylmuramate-alanine ligase releasing an ADP, hydrogen ion, a phosphate and a UDP-N-acetylmuramoyl-L-alanine. This compound interacts with D-glutamic acid and ATP through  UDP-N-acetylmuramoylalanine-D-glutamate ligase releasing ADP, A phosphate and UDP-N-acetylmuramoyl-L-alanyl-D-glutamate. The latter compound then interacts with meso-diaminopimelate in an ATP mediated ligation through a UDP-N-acetylmuramoylalanine-D-glutamate-2,6-diaminopimelate ligase resulting in ADP, phosphate, hydrogen ion and UDP-N-Acetylmuramoyl-L-alanyl-D-gamma-glutamyl-meso-2,6-diaminopimelate. This compound in turn with D-alanyl-D-alanine react in an ATP-mediated ligation through UDP-N-Acetylmuramoyl-tripeptide-D-alanyl-D-alanine ligase to produce UDP-N-acetyl-alpha-D-muramoyl-L-alanyl-gama-D-glutamyl-meso-2,6-diaminopimeloyl-Dalanyl-D-alanine and hydrogen ion, ADP, phosphate. UDP-N-acetyl-alpha-D-muramoyl-L-alanyl-gama-D-glutamyl-meso-2,6-diaminopimeloyl-Dalanyl-D-alanine interacts with di-trans,octa-cis-undecaprenyl phosphate through a phospho-N-acetylmuramoyl-pentapeptide-transferase, resulting in UMP and Undecaprenyl-diphospho-N-acetylmuramoyl-L-alanyl-D-glutamyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine which in turn reacts with a UDP-N-acetylglucosamine through a N-acetylglucosaminyl transferase to produce a hydrogen, UDP and ditrans,octacis-undecaprenyldiphospho-N-acetyl-(N-acetylglucosaminyl)muramoyl-L-alanyl-gamma-D-glutamyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine. This compound ends the cytoplasmic part of the pathway. ditrans,octacis-undecaprenyldiphospho-N-acetyl-(N-acetylglucosaminyl)muramoyl-L-alanyl-gamma-D-glutamyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine is transported through a lipi II flippase. Once in the periplasmic space, the compound reacts with a penicillin binding protein 1A prodducing a peptidoglycan dimer, a hydrogen ion, and UDP. The peptidoglycan dimer then reacts with a penicillin binding protein 1B  producing a peptidoglycan with D,D, cross-links and a D-alanine. "
What is the definition of Folate Biosynthesis?,"The biosynthesis of folic acid begins with a product of purine nucleotides de novo biosynthesis pathway, GTP. This compound  is involved in a reaction with water through a GTP cyclohydrolase 1 protein complex, resulting in a hydrogen ion, formic acid and 7,8-dihydroneopterin 3-triphosphate. The latter compound is dephosphatased through a dihydroneopterin triphosphate pyrophosphohydrolase resulting in the release of a pyrophosphate, hydrogen ion and 7,8-dihydroneopterin 3-phosphate. The latter compound reacts with water spontaneously resulting in the release of a phosphate and a 7,8 -dihydroneopterin. This compound reacts with a dihydroneopterin aldolase, releasing a glycoaldehyde and 6-hydroxymethyl-7,9-dihydropterin. The latter compound is phosphorylated with a ATP-driven 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase resulting in a (2-amino-4-hydroxy-7,8-dihydropteridin-6-yl)methyl diphosphate.Chorismate is metabolized by reacting with L-glutamine through a 4-amino-4-deoxychorismate synthase resulting in L-glutamic acid and 4-amino-4-deoxychorismate. The latter compound then reacts through an aminodeoxychorismate lyase resulting in pyruvic acid,hydrogen ion and p-aminobenzoic acid.  (2-amino-4-hydroxy-7,8-dihydropteridin-6-yl)methyl diphosphate and p-aminobenzoic acid react through a dihydropteroate synthase resulting in pyrophosphate and 7,8-dihydropteroic acid. This compound reacts with L-glutamic acid through an ATP driven bifunctional folylpolyglutamate synthetase / dihydrofolate synthetase resulting in a 7,8-dihydrofolate monoglutamate. This compound is reduced through an NADPH mediated dihydrofolate reductase resulting in a tetrahydrofate.This product goes on to a one carbon pool by folate pathway."
What is the definition of PRPP Biosynthesis?,"The biosynthesis of phosphoribosyl pyrophosphate begins with a product of the pentose phosphate, D-ribose 5-phosphate interact with a  phosphopentomutase  resulting in a Ribose 1-phosphate or it can be phosphorylated through an ATP driven ribose-phosphate diphosphokinase resulting in a release of a hydrogen ion, an AMP and a phosphoribosyl pyrophosphate. The latter compound is then involved in the purine nucleotides de novo biosynthesis pathway.Ribose 1-phosphate can interact spontaneously with ATP resulting in a release of hydrogen ion, ADP and a ribose 1,5-biphosphate. The latter compound is then phosphorylated through a ribose 1,5-bisphosphokinase resulting in the release of ADP and phosphoribosyl pyrophosphate. The latter compound is then involved in the purine nucleotides de novo biosynthesis pathway."
What is the definition of Purine Nucleotides De Novo Biosynthesis?,"The biosynthesis of purine nucleotides is a complex process that begins with a phosphoribosyl pyrophosphate. This compound interacts with water and L-glutamine through a amidophosphoribosyl transferase resulting in a pyrophosphate, L-glutamic acid and a 5-phosphoribosylamine. The latter compound proceeds to interact with a glycine through an ATP driven phosphoribosylamine-glycine ligase resulting in the addition of glycine to the compound. This reaction releases an ADP, a phosphate, a hydrogen ion and a N1-(5-phospho-β-D-ribosyl)glycinamide. The latter compound interacts with formic acid, through an ATP driven phosphoribosylglycinamide formyltransferase 2 resulting in a phosphate, an ADP, a hydrogen ion and a 5-phosphoribosyl-N-formylglycinamide. The latter compound interacts with L-glutamine, and water through an ATP-driven phosphoribosylformylglycinamide synthetase resulting in a release of a phosphate, an ADP, a hydrogen ion, a L-glutamic acid and a 2-(formamido)-N1-(5-phospho-D-ribosyl)acetamidine. The latter compound interacts with an ATP driven phosphoribosylformylglycinamide cyclo-ligase resulting in a release of ADP, a phosphate, a hydrogen ion and a 5-aminoimidazole ribonucleotide. The latter compound interacts with a hydrogen carbonate through an ATP driven N5-carboxyaminoimidazole ribonucleotide synthetase resulting in a release of a phosphate, an ADP, a hydrogen ion and a N5-carboxyaminoimidazole ribonucleotide.The latter compound then interacts with a N5-carboxyaminoimidazole ribonucleotide mutase resulting in a 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate. This compound interacts with an L-aspartic acid through an ATP driven phosphoribosylaminoimidazole-succinocarboxamide synthase resulting in a phosphate, an ADP, a hydrogen ion and a SAICAR. SAICAR interacts with an adenylosuccinate lyase resulting in a fumaric acid and an AICAR. AICAR interacts with a formyltetrahydrofolate through a AICAR transformylase / IMP cyclohydrolase resulting in a release of a tetrahydropterol mono-l-glutamate and a FAICAR. The latter compound, FAICAR, interacts in a reversible reaction through a AICAR transformylase / IMP cyclohydrolase resulting in a release of water and Inosinic acid. Inosinic acid can be metabolized to produce dGTP and dATP   three different methods each.dGTP: Inosinic acid, water and NAD are processed by IMP dehydrogenase resulting in a release of NADH, a hydrogen ion and Xanthylic acid. Xanthylic acid interacts with L-glutamine, and water through an ATP driven GMP synthetase resulting in pyrophosphate, AMP, L-glutamic acid, a hydrogen ion and Guanosine monophosphate. The latter compound is the phosphorylated by reacting with an ATP driven guanylate kinase resulting in a release of ADP and a Gaunosine diphosphate. Guanosine diphosphate can be metabolized in three different ways:       1.-Guanosine diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and a Guanosine triphosphate. This compound interacts with a reduced flavodoxin protein through a ribonucleoside-triphosphate reductase resulting in a oxidized flavodoxin a water moleculer and a dGTP       2.-Guanosine diphosphate interacts with a reduced NrdH glutaredoxin-like proteins through a ribonucleoside-diphosphate reductase 2 resulting in the release of an oxidized NrdH glutaredoxin-like protein, a water molecule and a dGDP. The dGDP is then phosphorylated by interacting with an ATP-driven nucleoside diphosphate kinase resulting in an ADP and dGTP.       3.-Guanosine diphosphate interacts with a reduced thioredoxin ribonucleoside diphosphate reductase 1 resulting in a release of a water molecule, an oxidized thioredoxin and a dGDP. The dGDP is then phosphorylated by interacting with an ATP-driven nucleoside diphosphate kinase resulting in an ADP and dGTP.dATP:Inosinic acid interacts with L-aspartic acid through an GTP driven adenylosuccinate synthase results in the release of GDP, a hydrogen ion, a phosphate and N(6)-(1,2-dicarboxyethyl)AMP. The latter compound is then cleaved by a adenylosuccinate lyase resulting in a fumaric acid and an Adenosine monophosphate. This compound is then phosphorylated by an adenylate kinase resulting in the release of ATP and an adenosine diphosphate. Adenosine diphosphate can be metabolized in three different ways:        1.-Adenosine diphosphate is involved in a reversible reaction by interacting with a hydrogen ion and a phosphate through a ATP synthase / thiamin triphosphate synthase resulting in a hydrogen ion, a water molecule and an Adenosine triphosphate. The adenosine triphosphate interacts with a reduced flavodoxin through a ribonucleoside-triphosphate reductase resulting in an oxidized flavodoxin, a water molecule and a dATP        2.- Adenosine diphosphate interacts with an reduced thioredoxin through a ribonucleoside diphosphate reductase 1 resulting in a release of a water molecule, a oxidized thioredoxin and a dADP. The dADP is then phosphorylated by a nucleoside diphosphate kinase resulting in the release of ADP and a dATP        3.- Adenosine diphosphate interacts with an reduced NrdH glutaredoxin-like protein through a ribonucleoside diphosphate reductase 2 resulting in a release of a water molecule, a oxidized glutaredoxin-like protein and a dADP. The dADP is then phosphorylated by a nucleoside diphosphate kinase resulting in the release of ADP and a dATP"
What is the definition of Fructose Metabolism?,"Fructose metabolism begins with the transport of Beta-D-fructofuranose through a fructose PTS permease, resulting in a Beta-D-fructofuranose 1-phosphate. This compound is phosphorylated by an ATP driven 1-phosphofructokinase resulting in a fructose 1,6-biphosphate. This compound can either react with a fructose bisphosphate aldolase class 1 resulting in D-glyceraldehyde 3-phosphate and a dihydroxyacetone phosphate or through a fructose biphosphate aldolase class 2 resulting in a D-glyceraldehyde 3-phosphate. This compound can then either react in a reversible triosephosphate isomerase resulting in a dihydroxyacetone phosphate or react with a phosphate through a NAD dependent Glyceraldehyde 3-phosphate dehydrogenase resulting in a glyceric acid 1,3-biphosphate. This compound is desphosphorylated by a phosphoglycerate kinase resulting in a 3-phosphoglyceric acid.This compound in turn can either react with a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase or a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 2-phospho-D-glyceric acid. This compound interacts with an enolase resulting in a phosphoenolpyruvic acid and water. Phosphoenolpyruvic acid can react either through a AMP driven phosphoenoylpyruvate synthase or a ADP driven pyruvate kinase protein complex resulting in a pyruvic acid.Pyruvic acid reacts with CoA through a NAD driven pyruvate dehydrogenase complex resulting in a carbon dioxide and a Acetyl-CoA which gets incorporated into the TCA cycle pathway."
What is the definition of Glycerol Metabolism?,"Glycerol metabolism  starts with glycerol is introduced into the cytoplasm through a glycerol channel GlpF Glycerol is then phosphorylated through an ATP mediated glycerol kinase resulting in a Glycerol 3-phosphate. This compound can also be obtained through a glycerophosphodiester reacting with water through a glycerophosphoryl diester phosphodiesterase or it can also be introduced into the cytoplasm through a glycerol-3-phosphate:phosphate antiporter. Glycerol 3-phosphate is then metabolized into a dihydroxyacetone phosphate in both aerobic or anaerobic conditions. In anaerobic conditions the metabolism is done through the reaction of glycerol 3-phosphate with a menaquinone mediated by a glycerol-3-phosphate dehydrogenase protein complex. In aerobic conditions, the metabolism is done through the reaction of glycerol 3-phosphate with ubiquinone mediated by a  glycerol-3-phosphate dehydrogenase [NAD(P]+].Dihydroxyacetone phosphate is then introduced into the fructose metabolism by turning a dihydroxyacetone into an isomer through a triosephosphate isomerase resulting in a D-glyceraldehyde 3-phosphate which in turn reacts with a phosphate through a NAD dependent Glyceraldehyde 3-phosphate dehydrogenase resulting in a glyceric acid 1,3-biphosphate. This compound is desphosphorylated by a phosphoglycerate kinase resulting in a 3-phosphoglyceric acid.This compound in turn can either react with a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase or a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 2-phospho-D-glyceric acid. This compound interacts with an enolase resulting in a phosphoenolpyruvic acid and water. Phosphoenolpyruvic acid can react either through a AMP driven phosphoenoylpyruvate synthase or a ADP driven pyruvate kinase protein complex resulting in a pyruvic acid. Pyruvic acid reacts with CoA through a NAD driven pyruvate dehydrogenase complex resulting in a carbon dioxide and a Acetyl-CoA which gets incorporated into the TCA cycle pathway."
What is the definition of Glycerol Metabolism II?,"Glycerol metabolism starts with glycerol is introduced into the cytoplasm through a glycerol channel GlpF Glycerol is then phosphorylated through an ATP mediated glycerol kinase resulting in a Glycerol 3-phosphate. This compound can also be obtained through sn-glycero-3-phosphocholine reacting with water through a glycerophosphoryl diester phosphodiesterase  producing a benzyl alcohol, a hydrogen ion and a glycerol 3-phosphate or  the campound can be introduced into the cytoplasm through a glycerol-3-phosphate:phosphate antiporter. Glycerol 3-phosphate is then metabolized into a dihydroxyacetone phosphate in both aerobic or anaerobic conditions. In anaerobic conditions the metabolism is done through the reaction of glycerol 3-phosphate with a menaquinone mediated by a glycerol-3-phosphate dehydrogenase protein complex. In aerobic conditions, the metabolism is done through the reaction of glycerol 3-phosphate with ubiquinone mediated by a glycerol-3-phosphate dehydrogenase [NAD(P]+]. Dihydroxyacetone phosphate is then introduced into the fructose metabolism by turning a dihydroxyacetone into an isomer through a triosephosphate isomerase resulting in a D-glyceraldehyde 3-phosphate which in turn reacts with a phosphate through a NAD dependent Glyceraldehyde 3-phosphate dehydrogenase resulting in a glyceric acid 1,3-biphosphate. This compound is desphosphorylated by a phosphoglycerate kinase resulting in a 3-phosphoglyceric acid.This compound in turn can either react with a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase or a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 2-phospho-D-glyceric acid. This compound interacts with an enolase resulting in a phosphoenolpyruvic acid and water. Phosphoenolpyruvic acid can react either through a AMP driven phosphoenoylpyruvate synthase or a ADP driven pyruvate kinase protein complex resulting in a pyruvic acid. Pyruvic acid reacts with CoA through a NAD driven pyruvate dehydrogenase complex resulting in a carbon dioxide and a Acetyl-CoA which gets incorporated into the TCA cycle pathway."
What is the definition of Glycerol Metabolism III (sn-Glycero-3-Phosphoethanolamine)?,"Glycerol metabolism starts with glycerol is introduced into the cytoplasm through a glycerol channel GlpF Glycerol is then phosphorylated through an ATP mediated glycerol kinase resulting in a Glycerol 3-phosphate. This compound can also be obtained through sn-glycero-3-phosphethanolamine reacting with water through a glycerophosphoryl diester phosphodiesterase producing a benzyl alcohol, a hydrogen ion and a glycerol 3-phosphate or the campound can be introduced into the cytoplasm through a glycerol-3-phosphate:phosphate antiporter. Glycerol 3-phosphate is then metabolized into a dihydroxyacetone phosphate in both aerobic or anaerobic conditions. In anaerobic conditions the metabolism is done through the reaction of glycerol 3-phosphate with a menaquinone mediated by a glycerol-3-phosphate dehydrogenase protein complex. In aerobic conditions, the metabolism is done through the reaction of glycerol 3-phosphate with ubiquinone mediated by a glycerol-3-phosphate dehydrogenase [NAD(P]+]. Dihydroxyacetone phosphate is then introduced into the fructose metabolism by turning a dihydroxyacetone into an isomer through a triosephosphate isomerase resulting in a D-glyceraldehyde 3-phosphate which in turn reacts with a phosphate through a NAD dependent Glyceraldehyde 3-phosphate dehydrogenase resulting in a glyceric acid 1,3-biphosphate. This compound is desphosphorylated by a phosphoglycerate kinase resulting in a 3-phosphoglyceric acid.This compound in turn can either react with a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase or a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 2-phospho-D-glyceric acid. This compound interacts with an enolase resulting in a phosphoenolpyruvic acid and water. Phosphoenolpyruvic acid can react either through a AMP driven phosphoenoylpyruvate synthase or a ADP driven pyruvate kinase protein complex resulting in a pyruvic acid. Pyruvic acid reacts with CoA through a NAD driven pyruvate dehydrogenase complex resulting in a carbon dioxide and a Acetyl-CoA which gets incorporated into the TCA cycle pathway."
What is the definition of Glycerol Metabolism IV (Glycerophosphoglycerol)?,"Glycerol metabolism starts with glycerol is introduced into the cytoplasm through a glycerol channel GlpF Glycerol is then phosphorylated through an ATP mediated glycerol kinase resulting in a Glycerol 3-phosphate. This compound can also be obtained through glycerophosphoglycerol reacting with water through a glycerophosphoryl diester phosphodiesterase producing a benzyl alcohol, a hydrogen ion and a glycerol 3-phosphate or the campound can be introduced into the cytoplasm through a glycerol-3-phosphate:phosphate antiporter. Glycerol 3-phosphate is then metabolized into a dihydroxyacetone phosphate in both aerobic or anaerobic conditions. In anaerobic conditions the metabolism is done through the reaction of glycerol 3-phosphate with a menaquinone mediated by a glycerol-3-phosphate dehydrogenase protein complex. In aerobic conditions, the metabolism is done through the reaction of glycerol 3-phosphate with ubiquinone mediated by a glycerol-3-phosphate dehydrogenase [NAD(P]+]. Dihydroxyacetone phosphate is then introduced into the fructose metabolism by turning a dihydroxyacetone into an isomer through a triosephosphate isomerase resulting in a D-glyceraldehyde 3-phosphate which in turn reacts with a phosphate through a NAD dependent Glyceraldehyde 3-phosphate dehydrogenase resulting in a glyceric acid 1,3-biphosphate. This compound is desphosphorylated by a phosphoglycerate kinase resulting in a 3-phosphoglyceric acid.This compound in turn can either react with a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase or a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 2-phospho-D-glyceric acid. This compound interacts with an enolase resulting in a phosphoenolpyruvic acid and water. Phosphoenolpyruvic acid can react either through a AMP driven phosphoenoylpyruvate synthase or a ADP driven pyruvate kinase protein complex resulting in a pyruvic acid. Pyruvic acid reacts with CoA through a NAD driven pyruvate dehydrogenase complex resulting in a carbon dioxide and a Acetyl-CoA which gets incorporated into the TCA cycle pathway."
What is the definition of Glycerol Metabolism V (Glycerophosphoserine)?,"Glycerol metabolism starts with glycerol is introduced into the cytoplasm through a glycerol channel GlpF Glycerol is then phosphorylated through an ATP mediated glycerol kinase resulting in a Glycerol 3-phosphate. This compound can also be obtained through glycerophosphoserine reacting with water through a glycerophosphoryl diester phosphodiesterase producing a benzyl alcohol, a hydrogen ion and a glycerol 3-phosphate or the campound can be introduced into the cytoplasm through a glycerol-3-phosphate:phosphate antiporter. Glycerol 3-phosphate is then metabolized into a dihydroxyacetone phosphate in both aerobic or anaerobic conditions. In anaerobic conditions the metabolism is done through the reaction of glycerol 3-phosphate with a menaquinone mediated by a glycerol-3-phosphate dehydrogenase protein complex. In aerobic conditions, the metabolism is done through the reaction of glycerol 3-phosphate with ubiquinone mediated by a glycerol-3-phosphate dehydrogenase [NAD(P]+]. Dihydroxyacetone phosphate is then introduced into the fructose metabolism by turning a dihydroxyacetone into an isomer through a triosephosphate isomerase resulting in a D-glyceraldehyde 3-phosphate which in turn reacts with a phosphate through a NAD dependent Glyceraldehyde 3-phosphate dehydrogenase resulting in a glyceric acid 1,3-biphosphate. This compound is desphosphorylated by a phosphoglycerate kinase resulting in a 3-phosphoglyceric acid.This compound in turn can either react with a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase or a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 2-phospho-D-glyceric acid. This compound interacts with an enolase resulting in a phosphoenolpyruvic acid and water. Phosphoenolpyruvic acid can react either through a AMP driven phosphoenoylpyruvate synthase or a ADP driven pyruvate kinase protein complex resulting in a pyruvic acid. Pyruvic acid reacts with CoA through a NAD driven pyruvate dehydrogenase complex resulting in a carbon dioxide and a Acetyl-CoA which gets incorporated into the TCA cycle pathway."
What is the definition of Oxidative Phosphorylation?,"The process of oxidative phosphorylation involves multiple interactions of ubiquinone with succinic acid, resulting in a fumaric acid and ubiquinol.Ubiquinone interacts with succinic acid through a succinate:quinone oxidoreductase resulting in a fumaric acid an ubiquinol. This enzyme has various cofactors, ferroheme b, 2FE-2S, FAD, and 3Fe-4S iron-sulfur cluster. Then 2 ubiquinol interact with oxygen and 4 hydrogen ion through a cytochrome bd-I terminal oxidase resulting in a 4 hydrogen ion transferred into the periplasmic space, 2  water returned into the cytoplasm and 2 ubiquinone, which stay in the inner membrane.The ubiquinone interacts with succinic acid through a succinate:quinone oxidoreductase resulting in a fumaric acid an ubiquinol. Then 2 ubiquinol interacts with oxygen and 4 hydrogen ion through a cytochrome bd-II terminal oxidase resulting in a 4 hydrogen ion transferred into the periplasmic space, 2 water returned into the cytoplasm and 2 ubiquinone, which stay in the inner membrane.The ubiquinone interacts with succinic acid through a succinate:quinone oxidoreductase resulting in a fumaric acid an ubiquinol. The 2 ubiquinol interact with oxygen and 8 hydrogen ion through a cytochrome bo terminal oxidase resulting in a 8 hydrogen ion transferred into the periplasmic space, 2 water returned into the cytoplasm and 2 ubiquinone, which stays in the inner membrane.The ubiquinone then interacts with 5 hydrogen ion through a NADH dependent ubiquinone oxidoreductase I resulting in NAD, hydrogen ion released into the periplasmic space and an ubiquinol. The ubiquinol is then processed reacting with oxygen, and 4 hydrogen through a ion cytochrome bd-I terminal oxidase resulting in 4 hydrogen ions released into the periplasmic space, 2 water molecules into the cytoplasm and 2 ubiquinones.The ubiquinone then interacts with 5 hydrogen ion through a NADH dependent ubiquinone oxidoreductase I resulting in NAD, hydrogen ion released into the periplasmic space and an ubiquinol.The 2 ubiquinol interact with oxygen and 8 hydrogen ion through a cytochrome bo terminal oxidase resulting in a 8 hydrogen ion transferred into the periplasmic space, 2 water returned into the cytoplasm and 2 ubiquinone, which stays in the inner membrane."
What is the definition of Phenylalanine Metabolism?,"The pathways of the metabolism of phenylalaline begins with the conversion of chorismate to prephenate through a P-protein (chorismate mutase:pheA). Prephenate then interacts with a hydrogen ion through the same previous enzyme resulting in a release of carbon dioxide, water and a phenolpyruvic acid. Three enzymes those enconde by tyrB, aspC and ilvE are involved in catalyzing the third step of these pathways, all three can contribute to the synthesis of phenylalanine: only tyrB and aspC contribute to biosynthesis of tyrosine.Phenolpyruvic acid can also be obtained from a reversivle reaction with ammonia, a reduced acceptor and a D-amino acid dehydrogenase, resulting in a water, an acceptor and a D-phenylalanine, which can be then transported into the periplasmic space by aromatic amino acid exporter.L-phenylalanine also interacts in two reversible reactions, one involved with oxygen through a catalase peroxidase resulting in a carbon dioxide and 2-phenylacetamide. The other reaction involved an interaction with oxygen through a phenylalanine aminotransferase resulting in a oxoglutaric acid and phenylpyruvic acid.L-phenylalanine can be imported into the cytoplasm through an aromatic amino acid:H+ symporter AroP.The compound can also be imported into the periplasmic space through a transporter: L-amino acid efflux transporter."
What is the definition of Sulfur Metabolism?,"The sulfur metabolism pathway starts in three possible ways. The first is the uptake of sulfate through an active transport reaction via a sulfate transport system containing an ATP-binding protein which hydrolyses ATP. Sulfate is converted by the sulfate adenylyltransferase enzymatic complex to adenosine phosphosulfate through the addition of adenine from a molecule of ATP, along with one phosphate group. Adenosine phosphosulfate is further converted to phoaphoadenosine phosphosulfate through an ATP hydrolysis and dehydrogenation reaction by the adenylyl-sulfate kinase. Phoaphoadenosine phosphosulfate is finally dehydrogenated and converted to sulfite by phosphoadenosine phosphosulfate reductase. This reaction requires magnesium, and  adenosine 3',5'-diphosphate is the bi-product. A thioredoxin is also oxidized. Sulfite can also be produced from the dehydrogenation of cyanide along with the conversion of thiosulfate to thiocyanate by the thiosulfate sulfurtransferase enzymatic complex. Sulfite next undergoes a series of reactions that lead to the production of pyruvic acid, which is a precursor for pathways such as gluconeogenesis. The first reaction in this series is the conversion of sulfite to hydrogen sulfide through hygrogenation and the deoxygenation of sulfite to form a water molecule. The reaction is catalyzed by the sulfite reductase [NADPH] flavoprotein alpha and beta components. Siroheme, 4Fe-4S, flavin mononucleotide, and FAD function as cofactors or prosthetic groups. Hydrogen sulfide next undergoes dehydrogenation in a reversible reaction to form L-Cysteine and acetic acid, via the cysteine synthase complex and the coenzyme pyridoxal 5'-phosphate. L-Cysteine is dehydrogenated and converted to 2-aminoacrylic acid (a bronsted acid) and hydrogen sulfide(which may be reused) by a larger enzymatic complex composed of cysteine synthase A/B, protein malY, cystathionine-β-lyase, and tryptophanase, along with the coenzyme pyridoxal 5'-phosphate. 2-aminoacrylic acid isomerizes to 2-iminopropanoate,  which along with a water molecule and a hydrogen ion is lastly converted to pyruvic acid and ammonium in a spontaneous fashion. The second possible initial starting point for sulfur metabolism is the import of taurine(an alternate sulfur source) into the cytoplasm via the taurine ABC transporter complex. Taurine, oxoglutaric acid, and oxygen are converted to sulfite by the alpha-ketoglutarate-dependent taurine dioxygenase. Carbon dioxide, succinic acid, and aminoacetaldehyde are bi-products of this reaction. Sulfite next enters pyruvic acid synthesis as already described.The third variant of sulfur metabolism starts with the import of an alkyl sulfate into the cytoplasm via an aliphatic sulfonate ABC transporter complex which hydrolyses ATP. The alkyl sulfate is dehydrogenated and along with oxygen is converted to sulfite and an aldehyde by the FMNH2-dependent alkanesulfonate monooxygenase enzyme. Water and flavin mononucleotide(which is used in a subsequent reaction as a prosthetic group) are also produced. Sulfite is next converted to pyruvic acid by the process already described."
What is the definition of Sulfur Metabolism (Butanesulfonate)?,"The sulfur metabolism pathway starts in three possible ways. The first is the uptake of sulfate through an active transport reaction via a sulfate transport system containing an ATP-binding protein which hydrolyses ATP. Sulfate is converted by the sulfate adenylyltransferase enzymatic complex to adenosine phosphosulfate through the addition of adenine from a molecule of ATP, along with one phosphate group. Adenosine phosphosulfate is further converted to phoaphoadenosine phosphosulfate through an ATP hydrolysis and dehydrogenation reaction by the adenylyl-sulfate kinase. Phoaphoadenosine phosphosulfate is finally dehydrogenated and converted to sulfite by phosphoadenosine phosphosulfate reductase. This reaction requires magnesium, and adenosine 3',5'-diphosphate is the bi-product. A thioredoxin is also oxidized. Sulfite can also be produced from the dehydrogenation of cyanide along with the conversion of thiosulfate to thiocyanate by the thiosulfate sulfurtransferase enzymatic complex. Sulfite next undergoes a series of reactions that lead to the production of pyruvic acid, which is a precursor for pathways such as gluconeogenesis. The first reaction in this series is the conversion of sulfite to hydrogen sulfide through hygrogenation and the deoxygenation of sulfite to form a water molecule. The reaction is catalyzed by the sulfite reductase [NADPH] flavoprotein alpha and beta components. Siroheme, 4Fe-4S, flavin mononucleotide, and FAD function as cofactors or prosthetic groups. Hydrogen sulfide next undergoes dehydrogenation in a reversible reaction to form L-Cysteine and acetic acid, via the cysteine synthase complex and the coenzyme pyridoxal 5'-phosphate. L-Cysteine is dehydrogenated and converted to 2-aminoacrylic acid (a bronsted acid) and hydrogen sulfide(which may be reused) by a larger enzymatic complex composed of cysteine synthase A/B, protein malY, cystathionine-β-lyase, and tryptophanase, along with the coenzyme pyridoxal 5'-phosphate. 2-aminoacrylic acid isomerizes to 2-iminopropanoate, which along with a water molecule and a hydrogen ion is lastly converted to pyruvic acid and ammonium in a spontaneous fashion. The second possible initial starting point for sulfur metabolism is the import of taurine(an alternate sulfur source) into the cytoplasm via the taurine ABC transporter complex. Taurine, oxoglutaric acid, and oxygen are converted to sulfite by the alpha-ketoglutarate-dependent taurine dioxygenase. Carbon dioxide, succinic acid, and aminoacetaldehyde are bi-products of this reaction. Sulfite next enters pyruvic acid synthesis as already described. The third variant of sulfur metabolism starts with the import of an alkyl sulfate, in this case 1-butanesulfonate, into the cytoplasm via an aliphatic sulfonate ABC transporter complex which hydrolyses ATP. 1-butanesulfonate is dehydrogenated and along with oxygen is converted to sulfite and betaine aldehyde by the FMNH2-dependent alkanesulfonate monooxygenase enzyme. Water and flavin mononucleotide(which is used in a subsequent reaction as a prosthetic group) are also produced. Sulfite is next converted to pyruvic acid by the process already described."
What is the definition of Porphyrin Metabolism?,"The metabolism of porphyrin begins with with glutamic acid being processed by an ATP-driven glutamyl-tRNA synthetase by interacting with hydrogen ion and tRNA(Glu), resulting in amo, pyrophosphate and L-glutamyl-tRNA(Glu) Glutamic acid. Glutamic acid can be obtained as a result of L-glutamate metabolism pathway, glutamate / aspartate : H+ symporter GltP, glutamate:sodium symporter or a glutamate / aspartate ABC transporter .L-glutamyl-tRNA(Glu) Glutamic acid interacts with a NADPH glutamyl-tRNA reductase resulting in a NADP, a tRNA(Glu) and a (S)-4-amino-5-oxopentanoate. This compound interacts with a glutamate-1-semialdehyde aminotransferase resulting a 5-aminolevulinic acid. This compound interacts with a porphobilinogen synthase resulting in a hydrogen ion, water and porphobilinogen. The latter compound interacts with water resulting in hydroxymethylbilane synthase resulting in ammonium, and hydroxymethylbilane.  Hydroxymethylbilane can either be dehydrated to produce uroporphyrinogen I or interact with a uroporphyrinogen III synthase resulting in a water molecule and a uroporphyrinogen III.Uroporphyrinogen I interacts with hydrogen ion through a uroporphyrinogen decarboxylase resulting in a carbon dioxide and a coproporphyrinogen IUroporphyrinogen III can be metabolized into precorrin by interacting with a S-adenosylmethionine through a siroheme synthase resulting in hydrogen ion, an s-adenosylhomocysteine and a precorrin-1. On the other hand, Uroporphyrinogen III interacts with hydrogen ion through a uroporphyrinogen decarboxylase resulting in a carbon dioxide and a Coproporphyrinogen III.Precorrin-1 reacts with a S-adenosylmethionine through a siroheme synthase resulting in a S-adenosylhomocysteine and a Precorrin-2. The latter compound is processed by a NAD dependent uroporphyrin III C-methyltransferase [multifunctional] resulting in a NADH and a sirohydrochlorin. This compound then interacts with Fe 2+ uroporphyrin III C-methyltransferase [multifunctional] resulting in a hydrogen ion and a siroheme. The siroheme is then processed in sulfur metabolism pathway.Uroporphyrinogen III can be processed in anaerobic or aerobic condition. Anaerobic:Uroporphyrinogen III interacts with an oxygen molecule, a hydrogen ion through a coproporphyrinogen III oxidase resulting in water, carbon dioxide and protoporphyrinogen IX. The latter compound then interacts with an 3 oxygen molecule through a protoporphyrinogen oxidase resulting in 3 hydrogen peroxide and a Protoporphyrin IXAerobic:Uroporphyrinogen III reacts with S-adenosylmethionine through a coproporphyrinogen III dehydrogenase resulting in carbon dioxide, 5-deoxyadenosine, L-methionine and protoporphyrinogen IX. The latter compound interacts with a meanquinone through a protoporphyrinogen oxidase resulting in protoporphyrin IX.The protoporphyrin IX interacts with Fe 2+ through a ferrochelatase resulting in a hydrogen ion and a ferroheme b. The ferroheme b can either be incorporated into the oxidative phosphorylation as a cofactor of the enzymes involved in that pathway or it can interact with hydrogen peroxide through a catalase HPII resulting in a heme D. Heme D can then be incorporated into the oxidative phosphyrlation pathway as a cofactor of the enzymes involved in that pathway. Ferroheme b can also interact with water and a farnesyl pyrophosphate through a heme O synthase resulting in a release of pyrophosphate and heme O. Heme O is then incorporated into the Oxidative phosphorylation pathway."
What is the definition of Propanoate Metabolism?,"Starting from L-threonine, this compound is deaminated through a threonine deaminase resulting in a hydrogen ion, a water molecule and a (2z)-2-aminobut-2-enoate. The latter compound then isomerizes to a 2-iminobutanoate, This compound then reacts spontaneously with hydrogen ion and a water molecule resulting in a ammonium and a 2-Ketobutyric acid. The latter compound interacts with CoA through a pyruvate formate-lyase / 2-ketobutyrate formate-lyase resulting in a formic acid and a propionyl-CoA. Propionyl-CoA can then be processed either into a 2-methylcitric acid or into a propanoyl phosphate. Propionyl-CoA interacts with oxalacetic acid and a water molecule through a 2-methylcitrate synthase resulting in a hydrogen ion, a CoA and a 2-Methylcitric acid.The latter compound is dehydrated through a 2-methylcitrate dehydratase resulting in a water molecule and cis-2-methylaconitate. The latter compound is then dehydrated by a bifunctional aconitate hydratase 2 and 2-methylisocitrate dehydratase  resulting in a water molecule and methylisocitric acid. The latter compound is then processed by 2-methylisocitrate lyase resulting in a release of succinic acid and pyruvic acid. Succinic acid can then interact with a propionyl-CoA through a propionyl-CoA:succinate CoA transferase resulting in a propionic acid and a succinyl CoA. Succinyl-CoA is then isomerized through a methylmalonyl-CoA mutase resulting in a methylmalonyl-CoA. This compound is then decarboxylated through a methylmalonyl-CoA decarboxylase resulting in a release of Carbon dioxide and Propionyl-CoA. Propionyl-CoA interacts with a phosphate through a phosphate acetyltransferase / phosphate propionyltransferase resulting in a CoA and a propanoyl phosphate. Propionyl-CoA can react with a phosphate through a phosphate acetyltransferase / phosphate propionyltransferase resulting in a CoA and a propanoyl phosphate. The latter compound is then dephosphorylated through a ADP driven acetate kinase/propionate kinase protein complex resulting in an ATP and Propionic acid. Propionic acid can be processed by a reaction with CoA through a ATP-driven propionyl-CoA synthetase resulting in a pyrophosphate, an AMP and a propionyl-CoA."
What is the definition of Starch and Sucrose Metabolism?,"The metabolism of starch and sucrose begins with D-fructose interacting with a D-glucose in a reversible reaction through a maltodextrin glucosidase resulting in a water molecule and a sucrose. D-fructose is phosphorylated through an ATP driven fructokinase resulting in the release of an ADP, a hydrogen ion and a Beta-D-fructofuranose 6-phosphate. This compound can also be introduced into the cytoplasm through either a mannose PTS permease or a hexose-6-phosphate:phosphate antiporter. The Beta-D-fructofuranose 6-phosphate is isomerized through a phosphoglucose isomerase resulting in a Beta-D-glucose 6-phosphate. This compound can also be incorporated by glucose PTS permease or a hexose-6-phosphate:phosphate antiporter. The beta-D-glucose 6 phosphate can also be produced by a D-glucose being phosphorylated by an ATP-driven glucokinase resulting in a ADP, a hydrogen ion and a Beta-D-glucose 6 phosphate. The beta-D-glucose can produce alpha-D-glucose-1-phosphate  by two methods:1.-Beta-D-glucose is isomerized into an alpha-D-Glucose 6-phosphate and then interacts in a reversible reaction through a phosphoglucomutase-1 resulting in a alpha-D-glucose-1-phosphate.2.-Beta-D-glucose interacts with a putative beta-phosphoglucomutase resulting in a Beta-D-glucose 1-phosphate.  Beta-D-glucose 1-phosphate can be incorporated into the cytoplasm through a glucose PTS permease. This compound is then isomerized into a Alpha-D-glucose-1-phosphateThe beta-D-glucose can cycle back into a D-fructose by first interacting with D-fructose in a reversible reaction through a Polypeptide: predicted glucosyltransferase resulting in the release of a phosphate and a sucrose. The sucrose then interacts in a reversible reaction with a water molecule through a maltodextrin glucosidase resulting in a D-glucose and a D-fructose. Alpha-D-glucose-1-phosphate can produce glycogen in by two different sets of reactions:1.-Alpha-D-glucose-1-phosphate interacts with a hydrogen ion and an ATP through a glucose-1-phosphate adenylyltransferase resulting in a pyrophosphate and an ADP-glucose. The ADP-glucose then interacts with an amylose through a glycogen synthase resulting in the release of an ADP and an Amylose. The amylose then interacts with 1,4-α-glucan branching enzyme resulting in glycogen2.- Alpha-D-glucose-1-phosphate interacts with amylose through a maltodextrin phosphorylase resulting in a phosphate and a glycogen.Alpha-D-glucose-1-phosphate can also interacts with UDP-galactose through a galactose-1-phosphate uridylyltransferase resulting in a galactose 1-phosphate and a Uridine diphosphate glucose. The UDP-glucose then interacts with an alpha-D-glucose 6-phosphate through a trehalose-6-phosphate synthase resulting in a uridine 5'-diphosphate, a hydrogen ion and a Trehalose 6- phosphate. The latter compound can also be incorporated into the cytoplasm through a trehalose PTS permease. Trehalose interacts with a water molecule through a trehalose-6-phosphate phosphatase resulting in the release of a phosphate and an alpha,alpha-trehalose.The alpha,alpha-trehalose can also be obtained from glycogen being metabolized through a glycogen debranching enzyme resulting in a the alpha, alpha-trehalose. This compound ca then be hydrated through a cytoplasmic trehalase resulting in the release of an alpha-D-glucose and a beta-d-glucose. Alpha-D-glucose-1-phosphate can be metabolized to produce dTDP-Beta-L-rhamnose. This happens by Alpha-D-glucose-1-phosphate reacting with a dTTP and a hydrogen ion through a dTDP-glucose pyrophosphorylase resulting in the release of a pyrophosphate and a dTDP-alpha-D-glucose. This coumpound in turn reacts with a dTDP-glucose 4,6-dehydratase resulting in the release of a water molecule and a dTDP-4-dehydro-6-deoxy-alpha-D-glucopyranose. The latter compound reacts with a dTDP-4-dehydrorhamnose 3,5-epimerase resulting in the release of a dTDP-4-dehydro-beta-L-rhamnose. This compound in turn gets metabolized by a NADPH dependent dTDP-4-dehydrorhamnose reductase resulting in a release of a NADP and a dTDP-beta-L-rhamnoseGlycogen is then metabolized by reacting with a phosphate through a glycogen phosphorylase resulting in a alpha-D-glucose-1-phosphate and a dextrin. The dextrin is then hydrated through a glycogen phosphorylase-limit dextrin α-1,6-glucohydrolase resulting in the release of a debranched limit dextrin and a maltotetraose. This compound can also be incorporated into the cytoplasm through a maltose ABC transporter. The maltotetraose interacts with a phosphate through a maltodextrin phosphorylase releasing a alpha-D-glucose-1-phosphate and a maltotriose. The maltotriose can also be incorporated through a maltose ABC transporter. The maltotriose can then interact with water through a maltodextrin glucosidase resulting in a D-glucose and a D-maltose. D-maltose can also be incorporated through a maltose ABC transporter The D-maltose can then interact with a maltotriose through a amylomaltase resulting in a maltotetraose and a D-glucose. The D-glucose is then phosphorylated through an ATP driven glucokinase resulting in a hydrogen ion, an ADP and a Beta-D-glucose 6-phosphate"
What is the definition of Pyrimidine Metabolism?,"The metabolism of pyrimidines begins with L-glutamine interacting with water molecule and a hydrogen carbonate through an ATP driven carbamoyl phosphate synthetase resulting in a hydrogen ion, an ADP, a phosphate, an L-glutamic acid and a carbamoyl phosphate. The latter compound interacts with an L-aspartic acid through a aspartate transcarbamylase resulting in a phosphate, a hydrogen ion and a N-carbamoyl-L-aspartate. The latter compound interacts with a hydrogen ion through a dihydroorotase resulting in the release of a water molecule and a 4,5-dihydroorotic acid. This compound interacts with an ubiquinone-1 through a dihydroorotate dehydrogenase, type 2 resulting in a release of an ubiquinol-1 and an orotic acid. The orotic acid then interacts with a phosphoribosyl pyrophosphate through a orotate phosphoribosyltransferase resulting in a pyrophosphate and an orotidylic acid. The latter compound then interacts with a hydrogen ion through an orotidine-5 '-phosphate decarboxylase, resulting in an release of carbon dioxide and an Uridine 5' monophosphate. The Uridine 5' monophosphate process to get phosphorylated by an ATP driven UMP kinase resulting in the release of an ADP and an Uridine 5--diphosphate. Uridine 5-diphosphate can be metabolized in multiple ways in order to produce a Deoxyuridine triphosphate. 1.-Uridine 5-diphosphate interacts with a reduced thioredoxin through a ribonucleoside diphosphate reductase 1 resulting in the release of a water molecule and an oxidized thioredoxin and an dUDP. The dUDP is then phosphorylated by an ATP through a nucleoside diphosphate kinase resulting in the release of an ADP and a DeoxyUridine triphosphate. 2.-Uridine 5-diphosphate interacts with a reduced NrdH glutaredoxin-like protein through a Ribonucleoside-diphosphate reductase 1 resulting in a release of a water molecule, an oxidized NrdH glutaredoxin-like protein and a dUDP. The dUDP is then phosphorylated by an ATP through a nucleoside diphosphate kinase resulting in the release of an ADP and a DeoxyUridine triphosphate. 3.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate. The latter compound interacts with a reduced flavodoxin through ribonucleoside-triphosphate reductase resulting in the release of an oxidized flavodoxin, a water molecule and a Deoxyuridine triphosphate 4.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate The uridine triphosphate interacts with a L-glutamine and a water molecule through an ATP driven CTP synthase resulting in an ADP, a phosphate, a hydrogen ion, an L-glutamic acid and a cytidine triphosphate. The cytidine triphosphate interacts with a reduced flavodoxin through a ribonucleoside-triphosphate reductase resulting in the release of a water molecule, an oxidized flavodoxin and a dCTP. The dCTP interacts with a water molecule and a hydrogen ion through a dCTP deaminase resulting in a release of an ammonium molecule and a Deoxyuridine triphosphate. 5.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate The uridine triphosphate interacts with a L-glutamine and a water molecule through an ATP driven CTP synthase resulting in an ADP, a phosphate, a hydrogen ion, an L-glutamic acid and a cytidine triphosphate. The cytidine triphosphate then interacts spontaneously with a water molecule resulting in the release of a phosphate, a hydrogen ion and a CDP. The CDP then interacts with a reduced NrdH glutaredoxin-like protein through a ribonucleoside-diphosphate reductase 2 resulting in the release of a water molecule, an oxidized NrdH glutaredoxin-like protein and a dCDP. The dCDP is then phosphorylated through an ATP driven nucleoside diphosphate kinase resulting in an ADP and a dCTP. The dCTP interacts with a water molecule and a hydrogen ion through a dCTP deaminase resulting in a release of an ammonium molecule and a Deoxyuridine triphosphate. 6.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate The uridine triphosphate interacts with a L-glutamine and a water molecule through an ATP driven CTP synthase resulting in an ADP, a phosphate, a hydrogen ion, an L-glutamic acid and a cytidine triphosphate. The cytidine triphosphate then interacts spontaneously with a water molecule resulting in the release of a phosphate, a hydrogen ion and a CDP. The CDP interacts with a reduced thioredoxin through a ribonucleoside diphosphate reductase 1 resulting in a release of a water molecule, an oxidized thioredoxin and a dCDP. The dCDP is then phosphorylated through an ATP driven nucleoside diphosphate kinase resulting in an ADP and a dCTP. The dCTP interacts with a water molecule and a hydrogen ion through a dCTP deaminase resulting in a release of an ammonium molecule and a Deoxyuridine triphosphate. The deoxyuridine triphosphate then interacts with a water molecule through a nucleoside triphosphate pyrophosphohydrolase resulting in a release of a hydrogen ion, a phosphate and a dUMP. The dUMP then interacts with a methenyltetrahydrofolate through a thymidylate synthase resulting in a dihydrofolic acid and a 5-thymidylic acid. Then 5-thymidylic acid is then phosphorylated through a nucleoside diphosphate kinase resulting in the release of an ADP and thymidine 5'-triphosphate."
What is the definition of Colanic Acid Building Blocks Biosynthesis?,"The colonic acid building blocks biosynthesis starts with a Beta-D-Glucose undergoing a transport reaction mediated by a glucose PTS permease. The permease phosphorylates the Beta-D-Glucose, producing a Beta-D-Glucose 6-phosphate. This compound can either change to an Alpha-D-Glucose 6-phosphate spontaneously or into a fructose 6-phosphate through a glucose-6-phosphate isomerase. The latter compound can also be present in E.coli through the interaction of D-fructose and a mannose PTS permease which phosphorylate the D-fructose. Fructose 6-phosphate interacts in a reversible reaction with mannose-6-phosphate isomerase in order to produce a Alpha-D-mannose 6-phosphate. This compound can also be present in E.coli through the interaction of Alpha-D-mannose and a mannose PTS permease which phosphorylates the alpha-D-mannose. Alpha-D-mannose 6-phosphate interacts in a reversible reaction with a phosphomannomutase to produce a alpha-D-mannose 1-phosphate. This compound in turn with a hydrogen ion and gtp undergoes a reaction with a mannose-1-phosphate guanylyltransferase, releasing a pyrophosphate and producing a guanosine diphosphate mannose. Guanosine diphosphate mannose interacts with gdp-mannose 4,6-dehydratase releasing a water, and gdp-4-dehydro-6-deoxy-D-mannose. This compound in turn with hydrogen ion and NADPH interact with GDP-L-fucose synthase releasing NADP and producing a GDP-L-fucose.The Alpha-D-Glucose 6-phosphate interacts in a reversible reaction with phosphoglucomutase-1 to produce a alpha-D-glucose 1-phosphate. This in turn with UTP and hydrogen ion interact with UTP--glucose-1-phosphate uridyleltransferase releasing a pyrophosphate and UDP-glucose.UDP-glucose can either interact with galactose-1-phosphate uridylyltransferase to produce a UDP-galactose or in turn with NAD and water interact with UDP-glucose 6-dehydrogenase releasing a NADH and a hydrogen ion and producing a UDP-glucuronate.GDP-L-fucose, UDP-glucose, UDP-galactose and UDP-glucuronate are sugars that need to be activated in the form of nucleotide sugar prior to their assembly into colanic acid, also known as M antigen. Colanic acid is an extracellular polysaccharide which has been linked to a cluster of 19 genes(wca)."
What is the definition of Lac Operon ?,"The lac operon in E. coli produces three proteins that are used to metabolize lactose in the absence of glucose. If glucose is present in the cell, cAMP levels will be low, and only a small amount will be able to bind to the cAMP-activated global transcriptional regulator (CRP or CAP). Without cAMP bound, the protein is unactivated, and cannot bind to the activator binding site of the operon. However, when glucose levels are low, cAMP levels are higher, and more can bind to and activate CRP, allowing it to activate the operon. At the same time, if lactose levels in the cell are low, there will be minimal amounts of allolactose produced by any beta-galactosidase present currently in the cell. Allolactose is necessary to bind to the lactose operon repressor, and without allolactose bound to the repressor, it is tightly bound to the operator region of the operon. However, when concentrations of lactose are higher in the cell, more allolactose is produced, and when it binds to the repressor, the repressor cannot bind to the operator, freeing it and allowing RNA polymerase to bind. This, combined with the binding of the CRP protein to the activator binding site leads to all three genes in the operon being transcribed.The first gene, lacZ, encodes the protein beta-galactosidase, an enzyme that hydrolyzes beta-galactosides into monosaccharides. In this instance, it hydrolyzes lactose into glucose and galactose. In some cases, it can also cause the isomerization of lactose into allolactose.The second gene, lacY, encodes the protein lactose permease, which is a transport protein that pumps lactose into the cell by using a proton gradient that also flows into the cell.Finally, the last gene, lacA, encodes the protein galactoside O-acetyltransferase, an enzyme that catalyzes the transfer of the acetyl group of acetyl-CoA to beta-galactosides. This specific protein is not known to be important to the lac operon, but may be important in detoxifying the bacteria by preventing acetylated galactosides from re-entering the cell."
What is the definition of Secondary Metabolites: Methylerythritol Phosphate and Polyisoprenoid Biosynthesis?,"The biosynthesis of isoprenoids starts with a D-glyceraldehyde 3-phosphate interacting with a hydrogen ion through a 1-deoxyxylulose-5-phosphate synthase resulting in a carbon dioxide and 1-Deoxy-D-xylulose. The latter compound then interacts with a hydrogen ion through a NADPH driven 1-deoxy-D-xylulose 5-phosphate reductoisomerase resulting in a NADP and a 2-C-methyl-D-erythritol 4-phosphate. The latter compound then interacts with a cytidine triphosphate and a hydrogen ion through a 4-diphosphocytidyl-2C-methyl-D-erythritol synthase resulting in a pyrophosphate and a 4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol. The latter compound is then phosphorylated through an ATP driven 4-diphosphocytidyl-2-C-methylerythritol kinase resulting in a release of an ADP, a hydrogen ion and a 2-phospho-4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol. The latter compound then interacts with a 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase  resulting in the release of a 2-C-methyl-D-erythritol-2,4-cyclodiphosphate resulting in the release of a cytidine monophosphate and 2-C-methyl-D-erythritol-2,4-cyclodiphosphate. The latter compound then interacts with a reduced flavodoxin through a 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate synthase  resulting in the release of a water molecule, a hydrogen ion, an oxidized flavodoxin and a 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate. The compound 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate can interact with an NADPH,a hydrogen ion through a 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase  resulting in a NADP, a water molecule and either a Dimethylallylpyrophosphate or a Isopentenyl pyrophosphate. These two last compounds can be are isomers that can be produced through a isopentenyl diphosphate isomerase.Dimethylallylpyrophosphate interacts with the isopentenyl pyrophosphate through a geranyl diphosphate synthase / farnesyl diphosphate synthase resulting in a pyrophosphate and a geranyl--PP. The latter compound interacts with a Isopentenyl pyrophosphate through a geranyl diphosphate synthase / farnesyl diphosphate synthase resulting in the release of a pyrophosphate and a farnesyl pyrophosphate. The latter compound interacts with isopentenyl pyrophosphate either through a undecaprenyl diphosphate synthase resulting in a release of a pyrophosphate and a di-trans,octa-cis-undecaprenyl diphosphate or through a octaprenyl diphosphate synthase resulting in a pyrophosphate and an octaprenyl diphosphate"
What is the definition of Secondary Metabolites: Enterobacterial Common Antigen Biosynthesis?,"The biosynthesis of a enterobacterial common antigen can begin with a di-trans,octa-cis-undecaprenyl phosphate interacts with a Uridine diphosphate-N-acetylglucosamine through undecaprenyl-phosphate α-N-acetylglucosaminyl transferase resulting in a N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol and a Uridine 5'-monophosphate. The N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol then reacts with an UDP-ManNAcA from the Amino sugar and nucleotide sugar metabolism pathway. This reaction is metabolized by a UDP-N-acetyl-D-mannosaminuronic acid transferase resulting in a uridine 5' diphosphate, a hydrogen ion and a Undecaprenyl N-acetyl-glucosaminyl-N-acetyl-mannosaminuronate-4-acetamido-4,6-dideoxy-D-galactose pyrophosphate. Glucose 1 phosphate can be metabolize by interacting with a hydrogen ion and a thymidine 5-triphosphate by either reacting with a dTDP-glucose pyrophosphorylase or a dTDP-glucose pyrophosphorylase 2 resulting in the release of a pyrophosphate and a dTDP-D-glucose. The latter compound is then dehydrated through an dTDP-glucose 4,6-dehydratase 2 resulting in water and dTDP-4-dehydro-6-deoxy-D-glucose. The latter compound interacts with L-glutamic acid through a dTDP-4-dehydro-6-deoxy-D-glucose transaminase resulting in the release of oxoglutaric acid and dTDP-thomosamine. The latter compound interacts with acetyl-coa through a dTDP-fucosamine acetyltransferase resulting in a Coenzyme A, a hydrogen Ion and a TDP-Fuc4NAc. Undecaprenyl N-acetyl-glucosaminyl-N-acetyl-mannosaminuronate-4-acetamido-4,6-dideoxy-D-galactose pyrophosphate then interacts with a TDP--Fuc4NAc through a 4-acetamido-4,6-dideoxy-D-galactose transferase resulting in a hydrogen ion, a dTDP and a Undecaprenyl N-acetyl-glucosaminyl-N-acetyl-mannosaminuronate-4-acetamido-4,6-dideoxy-D-galactose pyrophosphate. This compound is then transported through a protein wzxE into the periplasmic space so that it can be incorporated into the outer membrane. "
What is the definition of Trp Operon?,"The trp operon in E. coli contains five genes that produce proteins that are used in the production of the amino acid tryptophan when needed by the cell. When tryptophan levels in the cell are high, tryptophan binds to the trp operon repressor protein, which activates it. The activated repressor then binds to the operator, preventing RNA polymerase from binding and transcribing the operon. However, when tryptophan concentrations in the cell are low, it doesn't bind to the repressor, preventing it from binding to the operator, and allowing transcription until the terminator after the trpA gene is reached. The trp operon is also regulated by the amount of useable trp tRNA present. Upon start of transcription, the leader peptide, encoded by the trpL gene, will begin to be transcribed. Because this peptide contains two trp residues next to each other, and trp is a relatively uncommon amino acid, if there is a low concentration of trp tRNA in the cell, it can cause the leader peptide to stall during transcription. This allows for the section of mRNA immediately after the stalled ribosome to form the anti-termination hairpin. This hairpin prevents the formation of the terminal hairpin that contains a termination sequence that would stop transcription after the leader peptide. Because the anti-termination hairpin is allowed to form, transcription of the rest of the operon can continue. However, when the cell contains a high concentration of trp tRNA, the transcription does not stall, which allows for the formation of the transcription terminator to form before the rest of the genes in the operon, preveinting their transcription.The trpE and trpD genes encode for anthranilate synthase components 1 and 2 respectively. These combine to create anthranilate synthase, which produces anthranilate and pyruvate from chorismate.The trpC gene encodes the tryptophan biosynthesis protein that takes the anthranilate from the previous protein and converts it in two steps to indole-3-glycerol.Finally, the trpB and trpA genes encode for tryptophan beta and alpha subunits respectively. Two of each subunit come together to form tryptophan synthase. This protein then takes the previous compound, as well as a molecule of L-serine, and catalzes their conversion into tryptophan, as well as water and D-glyceraldehyde-3-phosphate."
What is the definition of Secondary Metabolites: Glyoxylate Cycle?,"The glyoxylate cycle starts with the interaction of Acetyl-Coa with a water molecule and Oxalacetic acid interact through a Citrate synthase resulting in a release of a coenzyme a and citric acid. The citric acid gets dehydrated through a citrate hydro-lyase resulting in the release of a water molecule and cis-Aconitic acid. The cis-Aconitic acid is then hydrated in an reversible reaction through an aconitate hydratase resulting in an Isocitric acid. The isocitric acid then interacts in a reversible reaction through isocitrate lyase resulting in the release of a succinic acid and a glyoxylic acid. The glyoxylic acid then reacts in a reversible reaction with an acetyl-coa, and a water molecule in a reversible reaction, resulting in a release of a coenzyme A, a hydrogen ion and an L-malic acid. The L-malic acid interacts in a reversible reaction through a NAD driven malate dehydrogenase resulting in the release of NADH, a hydrogen ion and an Oxalacetic acid."
What is the definition of Secondary Metabolites: Trehalose Biosynthesis and Metabolism?,"Threhalose biosynthesis begins with an Alpha-D-glucose-1-phosphate interacting with an ATP through a glucose-1-phosphate adenylyltransferase resulting in the release of a pyrophosphate and an ADP-glucose. The latter compound interacts in a reversible reaction with an amylose through a glycogen synthase resulting in the release of an ADP and an amylose. Amylose then interacts in a reversible reaction with 1,4-α-glucan branching enzyme resulting in a glycogenGlycogen can also be produced by a reversible reaction with Amylose through a maltodextrin phosphorylase, releasing a phosphate and a glycogen.Glycogen is then transformed into trehalose through a glycogen debranching enzyme. Alpha Alpha Trehalose can be degraded by reacting with with a water molecule through a cytoplasmic trehalase resulting in the release of a Beta-D-glucose and an Alpha-D-glucose.phosphorylated  resulting in a  Beta-D-glucose 6-phosphate. This compound is phosphorylated  and can then join glycolysisAlpha Alpha Trehalose can be degraded in the periplasmic space by reacting with with a water molecule through a periplasmic trehalase resulting in the release of a Beta-D-glucose and an Alpha-D-glucose.The beta-D-glucose can be transported into the cytosol through a PTS permease where it is phosphorylated  resulting in a  Beta-D-glucose 6-phosphate. This compound can then join glycolysis"
What is the definition of Secondary Metabolites: Threonine Biosynthesis from Aspartate?,"The biosynthesis of threonine starts with L-aspartic acid being phosphorylated by an ATP driven Aspartate kinase resulting in an a release of an ADP and an L-aspartyl-4-phosphate. This compound interacts with a hydrogen ion through an NADPH driven aspartate semialdehyde dehydrogenase resulting in the release of a phosphate, an NADP and a L-aspartate-semialdehyde.The latter compound interacts with a hydrogen ion through a NADPH driven aspartate kinase / homoserine dehydrogenase resulting in the release of an NADP and a L-homoserine. L-homoserine is phosphorylated through an ATP driven homoserine kinase resulting in the release of an ADP, a hydrogen ion and a O-phosphohomoserine. The latter compound then interacts with a water molecule threonine synthase resulting in the release of a phosphate and an L-threonine. "
What is the definition of Secondary Metabolites: Cysteine Biosynthesis from Serine?,"The pathway starts with a 3-phosphoglyceric acid interacting with an NAD driven D-3-phosphoglycerate dehydrogenase / α-ketoglutarate reductase resulting in an NADH, a hydrogen ion and a phosphohydroxypyruvic acid. This compound then interacts with an L-glutamic acid through a 3-phosphoserine aminotransferase / phosphohydroxythreonine aminotransferase resulting in a oxoglutaric acid and a DL-D-phosphoserine. The latter compound then interacts with a water molecule through a phosphoserine phosphatase resulting in a phosphate and an L-serine. The L-serine interacts with an acetyl-coa through a serine acetyltransferase resulting in a release of a Coenzyme A and a O-Acetylserine. The O-acetylserine then interacts with a hydrogen sulfide through a O-acetylserine sulfhydrylase A resulting in an acetic acid, a hydrogen ion and an L-cysteine"
What is the definition of Secondary Metabolites: Valine and L-Leucine Biosynthesis from Pyruvate?,"The biosynthesis of Valine and L-leucine from pyruvic acid starts with pyruvic acid interacting with a hydrogen ion through a acetolactate synthase / acetohydroxybutanoate synthase resulting in a release of a carbon dioxide, a (S)-2-acetolactate. The latter compound then interacts with a hydrogen ion through a NADPH-driven acetohydroxy acid isomeroreductase resulting in the release of a NADP, a (R) 2,3-dihydroxy-3-methylvalerate. The latter compound is then dehydrated by a dihydroxy acid dehydratase resulting in the release of a water molecule an 3-methyl-2-oxovaleric acid. The 3-methyl-2-oxovaleric acid can produce an L-valine by interacting with a L-glutamic acid through a Valine Transaminase resulting in the release of a Oxoglutaric acid and a L-valine.The 3-methyl-2-oxovaleric acid then interacts with an acetyl-CoA and a water molecule through a 2-isopropylmalate synthase resulting in the release of a hydrogen ion, a Coenzyme A and a 2-Isopropylmalic acid. The isopropylimalic acid is then hydrated by interacting with a isopropylmalate isomerase resulting in a 3-isopropylmalate. This compound then interacts with an NAD driven 3-isopropylmalate dehydrogenase resulting in a NADH, a hydrogen ion and a 2-isopropyl-3-oxosuccinate. The latter compound then interacts with hydrogen ion spontaneously resulting in a carbon dioxide and a ketoleucine. The ketoleucine then interacts with a L-glutamic acid through a branched-chain amino-acid aminotransferase resulting in the oxoglutaric acid and L-leucine."
What is the definition of Secondary Metabolites: Leucine Biosynthesis?,"Leucine biosynthesis involves a five-step conversion process starting with a 3-methyl-2-oxovaleric acid interacting with acetyl-CoA and a water molecule through a 2-isopropylmalate synthase resulting in Coenzyme A, hydrogen Ion and 2-isopropylmalic acid. The latter compound reacts with isopropylmalate isomerase which dehydrates the compound resulting in a Isopropylmaleate. This compound reacts with  water through a isopropylmalate isomerase resulting in 3-isopropylmalate. This compound interacts with a NAD-driven D-malate / 3-isopropylmalate dehydrogenase results in 2-isopropyl-3-oxosuccinate. This compound interacts spontaneously with hydrogen resulting in the release of carbon dioxide and ketoleucine. Ketoleucine interacts in a reversible reaction with L-glutamic acid through a branched-chain amino-acid aminotransferase resulting in Oxoglutaric acid and L-leucine. 2-isopropylmalate synthase and terminal transaminase TyrB can both be suppressed by leucine. 2-keto-isovalerate and tyrosine can both inhibit the TyrB, which lead to absence of IlvE activity. Without IlvE activity, 2-ketoisocaproate could not convert to leucine since branched-chain amino-acid aminotransferase (IlvE) is the only enzyme to facilitate the reaction."
What is the definition of Secondary Metabolites: Ubiquinol Biosynthesis?,"The biosynthesis of ubiquinol starts the interaction of 4-hydroxybenzoic acid interacting with an octaprenyl diphosphate. The former compound comes from the chorismate interacting with a chorismate lyase resulting in the release of a pyruvic acid and a 4-hydroxybenzoic acid. On the other hand, the latter compound, octaprenyl diphosphate is the result of a farnesyl pyrophosphate interacting with an isopentenyl pyrophosphate through an octaprenyl diphosphate synthase resulting in the release of a pyrophosphate and an octaprenyl diphosphate.The 4-hydroxybenzoic acid interacts with octaprenyl diphosphate through a 4-hydroxybenzoate octaprenyltransferase resulting in the release of a pyrophosphate and a 3-octaprenyl-4-hydroxybenzoate. The latter compound then interacts with a hydrogen ion through a 3-octaprenyl-4-hydroxybenzoate carboxy-lyase resulting in the release of a carbon dioxide and a 2-octaprenylphenol. The latter compound interacts with an oxygen molecule and a hydrogen ion through a NADPH driven 2-octaprenylphenol hydroxylase resulting in a NADP, a water molecule and  a 2-octaprenyl-6-hydroxyphenol.The 2-octaprenyl-6-hydroxyphenol interacts with an S-adenosylmethionine through a bifunctional 3-demethylubiquinone-8 3-O-methyltransferase and 2-octaprenyl-6-hydroxyphenol methylase resulting in the release of a hydrogen ion, an s-adenosylhomocysteine and a 2-methoxy-6-(all-trans-octaprenyl)phenol. The latter compound then interacts with an oxygen molecule and a hydrogen ion through a NADPH driven 2-octaprenyl-6-methoxyphenol hydroxylase resulting in a NADP, a water molecule and a 2-methoxy-6-all trans-octaprenyl-2-methoxy-1,4-benzoquinol.The latter compound interacts with a S-adenosylmethionine through a bifunctional 2-octaprenyl-6-methoxy-1,4-benzoquinone methylase and S-adenosylmethionine:2-DMK methyltransferase resulting in a s-adenosylhomocysteine, a hydrogen ion and a 6-methoxy-3-methyl-2-all-trans-octaprenyl-1,4-benzoquinol. The 6-methoxy-3-methyl-2-all-trans-octaprenyl-1,4-benzoquinol. interacts with a reduced acceptor, an oxygen molecule through a 2-octaprenyl-3-methyl-6-methoxy-1,4-benzoquinone hydroxylase resulting in the release of a water molecule, an oxidized electron acceptor and a 3-demethylubiquinol-8. The latter compound then interacts with a S-adenosylmethionine through a bifunctional 3-demethylubiquinone-8 3-O-methyltransferase and 2-octaprenyl-6-hydroxyphenol methylase resulting in a hydrogen ion, a S-adenosylhomocysteine and a ubiquinol 8."
What is the definition of Secondary Metabolites: Shikimate Pathway?,The biosynthesis of shikimate  starts with D-Erythrose-4-phosphate getting transformed into 3-deoxy-D-arabino-heptulosonate-7-phosphate through a phospho-2-dehydro-3-deoxyheptonate aldolase. This is followed by a 3-dehydroquinate synthase converting the 3-deoxy-D-arabino-heptulosonate-7-phosphate into a 3-dehydroquinate which in turn is conveted to 3-dehydroshikimate through a 3-dehydroquinate dehydratase. A this point  3-dehydroshikimate can be turned into Shikimic acid through 2 different reactions involving an NADPH driven Quinate/shikimate dehydrogenase or a NADPH driven shikimate dehydrogenase 2.Shikimate can also be transported through a shikimate:H+ symporter.
What is the definition of Operon: Cytidyl Pyrophosphate Biosynthesis of Isoprenoids?,"The ispDF operon in E. coli contains two genes that encode proteins that are used to form building blocks for isoprenoid compounds. There is currently no information on the regulation of this operon.The first gene in the operon, ispD, also known as ygbP, encodes the protein 2-C-methyl-D-erythritol 4-phosphate (MEP) cytidylyltransferase. This protein  catalyzes the reaction of MEP, a hydrogen ion and cytidine triphosphate, which form a pyrophosphate molecule and 4-CDP-2-C-methyl-D-erythritol.The second gene, ispF, also known as ygbB or mecS, encodes for the protein 2-C-D-erythritol 2,4-cyclodiphosphate synthase. This protein is involved in the formation of isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), which are building blocks in the biosynthesis of isoprenoids, also known as terpenoids."
What is the definition of Operon: Elongation Factor?,"The tRNA-tufB operon in E. coli contains a total of five genes. Four of these encode tRNA molecules, while the final one encodes an elongation factor used in bacterial translation. The operon is regulated in two ways. It can be activated by the DNA-binding protein Fis, which binds upstream of the operon promoter and it increases gene transcription by altering the chromatin structure, making it easier for RNA polymerase to bind.The operon can also be negatively regulated by guanosine 3'-diphosphate 5-'triphosphate (ppgpp), a compound that is produced in E. coli in response to stress. ppgpp binds to the promoter region of the operon and inhibits transcription from occurring.The first four genes, thrU, tyrU, glyT and thrT are all transcribed into tRNA molecules. thrU and thrT are both threonine tRNAs with different anticodons (UGU and GGU), while tyrU is a tyrosine tRNA with the anticodin GUA, and glyT is a glycine tRNA with the anticodin UCC.The fifth gene in the operon, tufB, encodes the elongation factor Tu 2 protein. This protein binds the activated tRNAs in the ribosome, allowing for transcription to take place, and as such it is necessary for cell growth and function."
What is the definition of Operon: Iron Superoxide Dismutase?,"The sodB operon in E. coli contains one gene, sodB, that produces the protein superoxide dismutase. Superoxide dismutase takes superoxide radicals found in the cell and adds a hydrogen molecule to them, forming hydrogen peroxide and oxygen, which are less harmful to the cell.This operon is regulated by small regulator RNA molecules, which bind to the complementary mRNA present in the promoter and gene region of the operon. This prevents translation from occurring, so the protein cannot be produced. The operon is also regulated by DNA-binding transcriptional repressors, which instead bind to the  DNA and prevents transcription from occurring in various ways."
What is the definition of Operon: General Secretory Pathway?,"The gspCDEFGHIJKLMO operon in E. coli contains a total of twelve genes, which encode for the proteins that make up the type II secretion system (T2SS) protein. The T2SS is responsible for moving proteins such as toxins and enzymes that cause symptoms associated with bacterial infection across the two cell membranes of the bacteria. This operon is regulated by DNA-binding protein H-NS, which binds to the DNA of the promoter, changing its conformation and preventing the RNA polymerase from binding to the promoter and transcribing the genes in the operon.The first gene, gspC, encodes for the putative T2SS protein C, which makes up part of the inner membrane complex of the secretion system, along with the proteins produced by gspF, gspL and gspM. After these, gspD encodes for the putative T2SS protein for export D, which forms a homo-pentadecamer pore in the outer membrane of the bacteria, which allows the exported substances to exit the cell. gspE encodes protein subunit E, which is the secretion ATPase. This protein binds to ATP and hydrolyzes it, and the energy produced by this is used to construct and deconstruct the pseudopillus, which is involved in the movement of substances across the periplasm and out of the cell.Another complex that is formed is the pseudopilus, which is made from pseudopilin proteins encoded by gspG, gspH, gspI, gspJ and gspK. These proteins are all activated by the leader peptidase integral membrane protein encoded by gspO, which is found in the inner membrane and allows for the formation of mature pseudopilin proteins."
What is the definition of Phospholipid Biosynthesis?,"Phospholipids are membrane components in E. coli. The major phospholipids of E. coli are phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin. All phospholipids contain sn-glycerol-3-phosphate esterified with fatty acids at the sn-1 and sn-2 positions. The reaction starts from a glycerone phosphate (dihydroxyacetone phosphate) produced in glycolysis. The glycerone phosphate is transformed into an sn-glycerol 3-phosphate (glycerol 3 phosphate) by NADPH-driven glycerol-3-phosphate dehydrogenase. sn-Glycerol 3-phosphate is transformed to a 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid). This can be achieved by an sn-glycerol-3-phosphate acyltransferase that interacts either with a long-chain acyl-CoA or with an acyl-[acp]. The 1-acyl-sn-glycerol 3-phosphate is transformed into a 1,2-diacyl-sn-glycerol 3-phosphate (phosphatidic acid) through a 1-acylglycerol-3-phosphate O-acyltransferase. This compound is then converted into a CPD-diacylglycerol through a CTP phosphatidate cytididyltransferase. CPD-diacylglycerol can be transformed either into an L-1-phosphatidylserine or an L-1-phosphatidylglycerol-phosphate through a phosphatidylserine synthase or a phosphatidylglycerophosphate synthase, respectively. The L-1-phosphatidylserine transforms into L-1-phosphatidylethanolamine through a phosphatidylserine decarboxylase. On the other hand, L-1-phosphatidylglycerol-phosphate gets transformed into an L-1-phosphatidyl-glycerol through a phosphatidylglycerophosphatase. These 2 products combine to produce a cardiolipin and an ethanolamine. The L-1 phosphatidyl-glycerol can also interact with cardiolipin synthase resulting in a glycerol and a cardiolipin."
What is the definition of Taurine Metabolism I?,"Taurine is incorporated into the cytoplasm through a taurine ABC transporter. Once inside the cytoplasm, taurine interacts with an oxoglutaric acid and an oxygen through a taurine dioxygenase resulting in the release of succinic acid, sulfite , aminoacetaldehyde and carbon dioxide."
What is the definition of Phospholipid Biosynthesis CL(18:1(9Z)/14:0/14:0/14:0)?,"Phospholipids are membrane components in E. coli. The major phospholipids of E. coli are phosphatidylethanolamine, phosphatidylglycerol and cardiolipin. All phospholipids contain sn-glycerol-3-phosphate esterified with fatty acids at the sn-1 and sn-2 positions.The reaction starts from a glycerone phosphate (dihydroxyacetone phosphate) produced in glycolysis. The glycerone phosphate is transformed to a sn-glycerol 3-phosphate (glycerol 3 phosphate) by NADPH driven glycerol-3-phosphate dehydrogenase. Sn-glycerol 3-phosphate is transformed to a 1-acyl-sn-glycerol 3-phosphate(1-oleyl-2-lyso-phosphatidate , 1-palmitoylglycerol 3-phosphate , 1-stearoyl-sn-glycerol 3-phosphate). This can be achieve by a sn-glycerol-3-phosphate 1-0-acyltransferase that interacts either with a long-chain acyl-CoA or with an acyl-[acp]. The 1-acyl-sn-glycerol 3-phosphate is transformed into a  1,2-diacyl-sn-glycerol 3-phosphate through a 1-acylglycerol-3-phosphate O-acyltransferase. This compound is then converted into a CPD-diacylglycerol  through a CTP (phosphatidate cytididyltransferase. CPD-diacylglycerol can be transformed either to a L-1-phosphatidylserine or a L-1-phosphatidylglycerol-phosphate through a phosphatidylserine synthase or a phosphatidylglycerophosphate synthase respectively. The  L-1-phosphatidylserine transforms into L-1-phosphatidylethanolamine through a phosphatidylserine decarboxylase, o the other hand L-1-phosphatidylglycerol-phosphate gets transformed into a L-1-phosphatidyl-glycerol through  a phosphatidylglycerophosphatase. These 2 products combines produce a cardiolipin  and a ethanolamine.The L-1 phosphatidyl-glycerol can also interact with cardiolipin synthase resulting in a glycerol and a cardiolipin."
What is the definition of One Carbon Pool by Folate?,"Dihydrofolic acid, a product of the folate biosynthesis pathway, can be metabolized by multiple enzymes. Dihydrofolic acid can be reduced by a NADP-driven dihydrofolate reductase resulting in a NADPH, hydrogen ion and folic acid. Dihydrofolic acid can also be reduced by an NADPH-driven dihydrofolate reductase resulting in a NADP and a tetrahydrofolic acid. Folic acid can also produce a tetrahydrofolic acid through a NADPH-driven dihydrofolate reductase. Dihydrofolic acid also interacts with 5-thymidylic acid through a thymidylate synthase resulting in the release of dUMP and 5,10-methylene-THFTetrahydrofolic acid can be converted into 5,10-methylene-THF through two different reversible reactions.Tetrahydrofolic acid interacts with a S-Aminomethyldihydrolipoylprotein through a aminomethyltransferase resulting in the release of ammonia, a dihydrolipoylprotein and 5,10-Methylene-THFTetrahydrofolic acid interacts with L-serine through a glycine hydroxymethyltransferase resulting in a glycine, water and 5,10-Methylene-THF.The compound 5,10-methylene-THF reacts with an NADPH dependent methylenetetrahydrofolate reductase [NAD(P)H] resulting in NADP and 5-Methyltetrahydrofolic acid. This compound interacts with homocysteine through a methionine synthase resulting in L-methionine and tetrahydrofolic acid.Tetrahydrofolic acid can be metabolized into 10-formyltetrahydrofolate through 4 different enzymes:1.- Tetrahydrofolic acid interacts with FAICAR through a phosphoribosylaminoimidazolecarboxamide formyltransferase resulting in a 1-(5'-Phosphoribosyl)-5-amino-4-imidazolecarboxamide and a 10-formyltetrahydrofolate2.-Tetrahydrofolic acid interacts with 5'-Phosphoribosyl-N-formylglycinamide through a phosphoribosylglycinamide formyltransferase 2 resulting in a Glycineamideribotide and a 10-formyltetrahydrofolate3.-Tetrahydrofolic acid interacts with Formic acid through a formyltetrahydrofolate hydrolase resulting in water and a 10-formyltetrahydrofolate4.-Tetrahydrofolic acid interacts with  N-formylmethionyl-tRNA(fMet) through a 10-formyltetrahydrofolate:L-methionyl-tRNA(fMet) N-formyltransferase resulting in a L-methionyl-tRNA(Met) and a 10-formyltetrahydrofolate10-formyltetrahydrofolate can interact with a hydrogen ion through a bifunctional 5,10-methylene-tetrahydrofolate dehydrogenase resulting in water and 5,10-methenyltetrahydrofolic acid. Tetrahydrofolic acid can be metabolized into 5,10-methenyltetrahydrofolic acid  by reacting with a 5'-phosphoribosyl-a-N-formylglycineamidine through a phosphoribosylglycinamide formyltransferase 2 resulting in water, glycineamideribotide and  5,10-methenyltetrahydrofolic acid. The latter compound can either interact with water through an aminomethyltransferase resulting in a N5-Formyl-THF, or it can interact with a NADPH driven bifunctional 5,10-methylene-tetrahydrofolate dehydrogenase resulting in a NADP and 5,10-Methylene THF."
What is the definition of Operon: DNA Biosynthesis/Heat Shock Protein?,"The dnaKJ operon in E. coli contains two genes which produce two chaperone and heat shock proteins. Heat shock proteins are induced when cellular stress is present. In addition to heat shock, this stress can also be caused by toxins such as heavy metals in the cell's environment. In this case, the operon is activated by RNA polymerase sigma factor RpoH, also know as sigma 32 or sigma H. This protein is produced when the bacteria is exposed to heat or other stress, and allows other heat shock proteins to be expressed.The first gene in the operon, dnaK, encodes the protein chaperone DnaK, also known as the 70 kilodalton heat shock protein (Hsp70). This chaperone binds to partially synthesized proteins and prevents them from aggregating before folding can occur. It can also bind to proteins that are transported across the cell membrane, as they remain unfolded until they are in place and are at risk for aggregation. When the cell is stressed, proteins can become damaged, leading to unfolding and aggregation. Hsp70 can bind to these proteins, preventing aggregation and allowing proper refolding.The second gene, dnaJ, encodes the protein chaperone DnaJ, which is also known as the 40 kilodalton heat shock protein (Hsp40). This protein also interacts with unfolded protein chains to prevent their aggregation"
What is the definition of Operon: tRNA Synthetase & Peptidase?,"The ribF-ileS-lspA-fkpB-ispH operon in E. coli contains five genes that encode for various proteins. There are currently no known activators and repressors of this operon.The first gene, ribF, encodes for a bifunctional riboflavin kinase and FMN adenylyltransferase. In the cell, it is used to convert riboflavin to FMN, and then FMN to FAD.The second gene, ileS, encodes the isoleucine tRNA ligase or synthetase, which catalyzes the attachment of the amimno acid isoleucine onto its tRNA, forming a charged tRNA.The third gene, lspA, encodes a lipoprotein signal peptidase. This protein cleaves signal peptides from prolipoproteins, forming the mature lipoprotein, as well as a free signal peptide which is then degraded.The fourth gene, fkpB, encodes a peptidyl-prolyl cis-trans isomerase which works as an isomerase, and also posesses a chaperone activity, assisting in the folding of several ribosomal proteins.The final gene, ispH, encodes 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate (HMBPP) reductase. This protein catalyzes the conversion of HMBPP into both dimethylallyl diphosphate (DMAPP) and isopentenyl diphosphate (IPP) as part of the methylerythritol phosphate pathway involved in isoprenoid biosynthesis. "
What is the definition of Operon: Carbamoyl Phosphate Synthetase?,"The carAB operon in E. coli contains two genes which produce the alpha and beta, or small and large chains of the carbamoyl-phosphate synthase protein. This protein is involved in the L-arginine biosynthesis pathway, and because of this, it can be repressed by the arginine repressor protein. This repressor is preesent when arginine is, preventing the biosynthesis of excess arginine.The first gene in this operon, carA, encodes the alpha or small chain of carbamoyl-phosphate synthase. The second gene, carB, encodes the beta or large chain of the same protein. One of each subunit combines in a heterodimer, which then interact with three other heterodomers to form the final carbamoyl-phosphate synthase protein. This protein is used in the formation of carbamoyl phosphate from glutamine, hydrogen carbonate, ATP and water. This reaction is part of the L-arginine biosynthesis pathway."
What is the definition of Operon: Carnitine Operon?,"The caiTABCDE operon in E. coli contains six genes that produce proteins involved in the anaerobic metabolism of carnitine. This operon can be activated by the aerobic respiration control protein ArcA, which binds to several places upstream of the promoter. This binding activates transcription in the proper conditions, such as the need for fermentative metabolism. The operon can also be repressed by the DNA-binding protein H-NS. This protein binds to and alters the structure of DNA, suppressing the genes until it is removed. Finally, the caiA gene mRNA can specifically be prevented from being translated by small regulatory RNA that binds to the transcript, while the other genes are translated normally.The first gene in the operon, caiT, encodes for the L-carnitine/gamma butyrobetaine antiporter protein, which is responsible for transporting methyl-L-carninte into the cell, while transporting gamma butyrobetaine out of it.The second gene, caiA, encodes crotonobetainyl-CoA reductase, a protein that catalyzes the conversion of crotonobetainyl-CoA into gamma-butyrobetainyl-CoA. This protein is thought to interact with L-carnitine CoA-transferase, the protein encoded by caiB, which transfers the CoA from gamma-butyrobetainyl-CoA to L-carnitine, forming L-carnityl-CoA and gamma-butyrobetaine. It can also transfer between crotonobetainyl-CoA and L-carnitine.The fourth gene in the operon, caiC, encodes a crotonobetaine/carnitine CoA ligase, which like caiB catalyzes the reversible transfer of CoA between carnitine, gamma-butyrobetaine and crotobetaine.The fifth gene, caiD, encodes carnitinyl-CoA dehydratase, which reversibly removes a water molecule from crotonobetainyl-CoA, forming carnitinyl-CoA.The final gene, caiE, encodes a putative transferase whose function is currently unknown. However, when the protein is overexpressed, it functions similarly to caiB and caiD, as a CoA ligase and dehydratase."
What is the definition of Operon: Redox Process?,"The fixABCX operon in E. coli contains four genes which encode for proteins that are potentially used in the anaerobic metabolism of carnitine, similar to those in the caiTABCDE operon. This operon can be activated by the cAMP-activated global transcriptional regulator CRP. Both the fix and cai operons are expressed in anaerobic conditions to metabolize carnitine, and they are found very close to one another in the genome, in opposite directions.The first gene, fixA, encodes for a protein which, with the protein produced by fixB, form a heterodimer protein. This protein may work as an electron transfer proteins, due to their similarity to electron transport flavoproteins in mammals.The third gene, fixC, encodes a protein that may be part of an electron transfer system in the anaerobic metabolism of carnitine.The final gene, fixX, encodes a ferredoxin-like protein involved in carnitine reduction."
What is the definition of Operon: 16S Ribosomal RNA Modification & Chaperone?,"The surA-pdxA-rsmA-apaGH operon in E. coli contains five genes that are involved in various functions in the cell. DNA-binding protein Fis can bind to the promoter of this operon, allowing RNAP to bind and transcribe the operon. It can also bind to a promoter upstream of pdxA, and this promoter allows for transcription of the pdxA-rsmA transcription unit.The first gene, surA, encodes a chaperone protein that is involved in the proper folding of outer membrane proteins, and is essential for the formation of the bacteria's pilus.The second gene, pdxA, encodes for 4-hydroxythreonine-4-phosphate dehydrogenase, an envyme involved in the biosynthesis of pyridoxal 5'-phosphate.The third gene, rsmA, encodes ribosomal RNA small subunit methyltransfeerase A, a protein that methylates 16S rRNA, and may be important in the formation of 30S subunits of rRNA.The fourth gene, apaG, produces a protein with currently unknown function.The final gene, apaH, produces diadenosine tetraphosphatase, which hydrolyzes diadenosine tetraphosphatase into two molecules of ADP."
What is the definition of ara Operon?,"The araBAD operon in E. coli contains three genes which encode proteins involved in the metabolism of L-arabinose into a form useable by the pentose phosphate pathway.The operon can be repressed by the arabinose operon regulatory protein, a protein dimer that is produced  in the cell. When arabinose is not present, it binds to the DNA in two specific locations, forming a loop in the DNA and preventing transcription from occurring.Inversely, the operon can be activated by the same arabinose operon regulatory protein in the presence of arabinose. In this case, the arabinose binds to the protein dimer, preventing it from forming the DNA loop and instead binding to the activator binding site upstream of the promoter. This binding helps RNA polymerase to bind and transcribe the operon. Finally, the araBAD operon functions like the lac operon, which only produces its enzymes in the absence of glucose. This is regulated by the cAMP-activated global transcriptional regulator (CRP). In the absence of glucose, cAMP levels build up in the cell, and it can bind to and activate CRP. The presence of both activated CRP and the arabinose operon regulatory protein promote the binding of RNA polymerase.The first gene in the operon, araB, encodes ribulokinase, an enzyme that irreversibly converts L-ribulose to L-ribulose-5-phsophate. The second gene, araA, encodes L-arabinose isomerase, an enzyme that convertsz L-arabinose to L-ribulose. This enzyme is the first step in the metabolism of arabinose.In between araA and araD are several non-coding extragenic sites.Finally, the last gene in the operon, araD, encodes L-ribulose-5-phosphate 4-epimerase, a protein that  converts L-ribulose-5-phosphate to D-xylulose-5-phosphate, which then is used in the pentose phosphate pathway."
What is the definition of Operon: Leucine Biosynthesis ?,"The leu operon of Escherichia coli is a polycystronic operon involved in the biosynthesis of leucine. RNA polymerase sigma 70 bind to promoter of leu operon so that it can enable the facilitation of transcription of gene leuA, leuB, leuC and tRNA(Ala). The product of these genes are 2-isopropylmalate synthase, 3-isopropylmalate dehydrogenase, 3-isopropylmalate dehydratase large subunit and 3-isopropylmalate dehydratase small subunit. "
What is the definition of Operon: Acetolactate Synthase III Activation?,"The ilvIH operon of Escherichia coli encodes acetohydroxyacid synthase III. Leucine-responsive regulatory protein binds two sites that is upstream of ilvlH promoter (-260 and -190; -80 and -60). Then, RNA polymerase sigma 70 will bind to ilvlH promoter to facilitate the transcription of gene ilvI and ilvH, which generate two enzymes: acetolactate synthase isozyme 3 large subunit and acetolactate synthase isozyme 3 small subunit."
What is the definition of Operon: Acetolactate Synthase III Inactivation?,"The ilvIH operon of Escherichia coli encodes acetohydroxyacid synthase III. Leucine-responsive regulatory protein binds two sites that is upstream of ilvlH promoter (-260 and -190; -80 and -60). Then, RNA polymerase sigma 70 will bind to ilvlH promoter to facilitate the transcription of gene ilvI and ilvH, which generate two enzymes: acetolactate synthase isozyme 3 large subunit and acetolactate synthase isozyme 3 small subunit. Expression of this operon is repressed by the presence of Leucine, but not no other branched amino acids"
"What is the definition of Operon: murGC, Peptidoglycan Synthesis?","The probable peptidoglycan synthesis genes from Escherichia coli constitute a polycistronic operon with a unique promoter. Gene murG, murC and ddlB will be facilitated for transcription. These gene will encode to set of proteins that are responsible for cell wall formation. Peptidoglycan (murein) is a polymer that is consisted of amino acids and sugar, which is essential for cell wall formation. In details, the polymer will form mesh-like layer at the outside of plasma membrane in most bacteria."
What is the definition of Adenosylcobalamin Salvage from Cobinamide?,"Cobinamide is incorporated from the extracellular space through a transport system into the cytosol. Once inside the cytosol, cobinamide interacts with ATP through a cobinamide adenosyl transferase resulting in the release of a triphosphate and an adenosylcobinamide. The latter compound is then phosphorylated through an ATP-dependent cobinamide kinase resulting in the release of ADP, a hydrogen ion and adenosyl-cobinamide phosphate. This last compound then interacts with GTP and a hydrogen ion through a cobinamide-P guanylyltransferase resulting in the release of a pyrophosphate and an adenosylcobinamide-GDP.A dimethylbenzimidazole interacts with a nicotinate D-ribonucleotide through a nicotinate-nucleotide dimethylbenzumidazole phosphoribosyltransferase resulting in the release of a nicotinate, a hydrogen ion and an alpha-ribazole 5' phosphate.The adenosylcobinamide-GDP and the alpha-ribazole 5' phosphate interact together through a cobalamin 5' phosphate synthase resulting in the release of a hydrogen ion, a GMP and Adenosylcobalamin 5'-phosphate. The latter compound then interacts with a water molecule through an adenosylcbalamin 5' phosphate phosphatase resulting in the release of a phosphate and a coenzyme B12.Likewise a cobalamin molecule can interact with ATP through a cobalamin adenosyltransferase resulting in the release of a triphosphate and a coenzyme B12"
What is the definition of Purine Degradation?,"Pseudouridine is phosphorylated by interacting with atp and a psuK resulting in the release of an ADP, a hydrogen ion and a pseudouridine 5'-phosphate. The latter compound then reacts with water through a pseudouridine 5'-phosphate glycosidase resulting in the release of  a uracil and D-ribofuranose 5-phosphate"
What is the definition of GTP Degradation and Molybdenum Cofactor Biosynthesis?,"GTP, produced in the nucleotide de novo biosyntheis pathway, interacts with a water molecule through a GTP cyclohydrolase resulting in a formate, hydrogen ion and a 7,8-dihydroneopterin 3'-triphosphate. The latter compound interacts with a water molecule through a dihydroneopterin triphosphate pyrophosphohydrolase resulting in the release of a pyrophosphate, a hydrogen ion and a 7,8-dihydroneopterin 3'-phosphate. The latter compound interacts with water spontaneously resulting in the release of a phosphate and a 7,8 dihydroneopterin. The latter compound interacts with a dihydroneopterin aldolase resulting in the release of a glycolaldehyde and a 6-hydroxymethyl-7,8-dihydropterin. This compound then is then diphosphorylated by reacting with a ATP driven 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase resulting in the release of a hydrogen ion, an AMP and 6-hydroxymethyl-7,8-dihydropterin diphosphate.GTP interacts with a cyclic pyranopterin monophosphate synthase resulting in the release of a diphosphate and a cyclic pyranopterin phosphate. The latter compound interacts with a thiocarboxylated small subunit of molybdopterin synthase (a protein) and a water molecule through a molybdopterin synthase resulting in the release of 4 hydrogen ions, 2 small subunits of molybdopterin synthase and a molybdopterin. The molybdopterin interacts with an ATP and a hydrogen ion through a molybdopterin adenylyltransferase resulting in the release of a diphosphate and a molybdopterin adenine dinucleotide. The latter compound is then metabolized by a hydrogen ion and a molybdate through a molybdopterin molybdenumtransferase resulting in the release of an AMP, a water molecule and a molybdopterin cofactor. The molybdopterin cofactor can procede to the guanylyl molybdenum cofactor biosynthesis pathway or it can be metabolized into a cytidylyl molybdenum cofactor by interacting with a CTP and a hydrogen ion through a molybdenym cofactor cytidylyltransferase resulting in the release of a pyrophosphate and a cytidyllyl molybdenum cofactor"
What is the definition of N-Oxide Electron Transfer?,"The pathway can start in various spots. First step in this case starts with NADH interacting with a menaquinone oxidoreductase resulting in the release of a NADH and a hydrogen Ion, at the same time in the inner membrane a menaquinone interacts with 2 electrons and 2 hydrogen ions thus releasing a menaquinol. This allows for 4 hydrogen ions to be transferred from the cytosol to the periplasmic space. The menaquinol then interacts with a trimethylamine N-oxide reductase resulting in the release of 2 hydrogen ion and 2 electrons. At the same time trimethylamine N-oxide and 3 hydrogen ions interact with the enzyme trimethylamine N-oxide reductase resulting in the release of a trimethylamine and a water molecule, this reaction happening in the periplasmic space.The second set of reactions starts with a hydrogen interacting with a menaquinone oxidoreductase resulting in the release of two electrons being released into the inner membrane which then react with with 2 hydrogen ion and a menaquinone to produce a menaquinol. This menaquinol then reacts with a trimethylamine N-oxide reductase following the same steps as mentioned before.The third set of reactions starts with with formate interacting with a formate dehydrogenase-O resulting in a release of carbon dioxide and a hydrogen ion, this releases 2 electrons that interact with a menaquinone and two hydrogen ions. This releases a menaquinol which then reacts with a trimethylamine N-oxide reductase following the same steps as mentioned before"
What is the definition of 2-Oxopent-4-enoate Metabolism ?,"The pathway starts with trans-cinnamate interacting with a hydrogen ion, an oxygen molecule, and a NADH through a cinnamate dioxygenase resulting in a NAD and a cis-3-(3-Carboxyethenyl)-3,5-cyclohexadiene-1,2-diol which then interact together through a  2,3-dihydroxy-2,3-dihydrophenylpropionate dehydrogenase resulting in the release of a hydrogen ion, an NADH molecule and a 2,3 dihydroxy-trans-cinnamate.The second way by which the 2,3 dihydroxy-trans-cinnamate is acquired is through a 3-hydroxy-trans-cinnamate interacting with a hydrogen ion, a NADH and an oxygen molecule through a 3-(3-hydroxyphenyl)propionate 2-hydroxylase resulting in the release of a NAD molecule, a water molecule and a 2,3-dihydroxy-trans-cinnamate.The compound 2,3 dihydroxy-trans-cinnamate then interacts with an oxygen molecule through a 2,3-dihydroxyphenylpropionate 1,2-dioxygenase resulting in a hydrogen ion and a 2-hydroxy-6-oxonona-2,4,7-triene-1,9-dioate. The latter compound then interacts with a water molecule through a 2-hydroxy-6-oxononatrienedioate hydrolase resulting in a release of a hydrogen ion, a fumarate molecule and (2Z)-2-hydroxypenta-2,4-dienoate. The latter compound reacts spontaneously to isomerize into a 2-oxopent-4-enoate. This compound is then hydrated through a 2-oxopent-4-enoate hydratase resulting in a 4-hydroxy-2-oxopentanoate. This compound then interacts with a 4-hydroxy-2-ketovalerate aldolase resulting in the release of a pyruvate, and an acetaldehyde. The acetaldehyde then interacts with a coenzyme A and a NAD molecule through a acetaldehyde dehydrogenase resulting in a hydrogen ion, a NADH and an acetyl-coa which can be incorporated into the TCA cycle"
What is the definition of Dimethyl Sulfoxide Electron Transfer ?,"The pathway can start in various spots. First step in this case starts with NADH interacting with a menaquinone oxidoreductase resulting in the release of a NADH and a hydrogen Ion, at the same time in the inner membrane a menaquinone interacts with 2 electrons and 2 hydrogen ions thus releasing a menaquinol. This allows for 4 hydrogen ions to be transferred from the cytosol to the periplasmic space. The menaquinol then interacts with a dimethyl sulfoxide reductase resulting in the release of 2 hydrogen ion and 2 electrons. At the same time dimethyl sulfoxide and 2 hydrogen ions interact with the enzyme resulting in the release of a dimethyl sulfide and a water molecule, this reaction happening in the periplasmic space.The second set of reactions starts with a hydrogen interacting with a menaquinone oxidoreductase resulting in the release of two electrons being released into the inner membrane which then react with with 2 hydrogen ion and a menaquinone to produce a menaquinol. This menaquinol then reacts with a trimethylamine N-oxide reductase following the same steps as mentioned before.The third set of reactions starts with with formate interacting with a formate dehydrogenase-O resulting in a release of carbon dioxide and a hydrogen ion, this releases 2 electrons that interact with a menaquinone and two hydrogen ions. This releases a menaquinol which then reacts with a trimethylamine N-oxide reductase following the same steps as mentioned before"
What is the definition of PreQ0 Metabolism?,"PreQ0 or 7-cyano-7-carbaguanine is biosynthesized by degrading GTP.GTP first interacts with water through a GTP cyclohydrolase resulting in the release of a formate, a hydrogen ion and a 7,8-dihydroneopterin 3'-triphosphate. The latter compound then interacts with water through a 6-carboxy-5,6,7,8-tetrahydropterin synthase resulting in a acetaldehyde, triphosphate, 2 hydrogen ion and 6-carboxy-5,6,7,8-tetrahydropterin. The latter compound then reacts spontaneously with a hydrogen ion resulting in the release of a ammonium molecule and a 7-carboxy-7-deazaguanine. This compound then interacts with ATP and ammonium through 7-cyano-7-deazaguanine synthase resulting in the release of water, phosphate, ADP, hydrogen ion and a 7-cyano-7-carbaguanine. The degradation of 7-cyano-7-deazaguanine can lead to produce a preQ1 or a queuine by reacting with 3 hydrogen ions and 2 NADPH through a 7-cyano-7-deazaguanine reductase. PreQ1 then interacts with a guanine 34 in tRNA through a tRNA-guanine transglycosylase resulting in a release of a guanine and a 7-aminomethyl-7-deazaguanosine 34 in tRNA. This nucleic acid then interacts with SAM through a S-adenosylmethionine tRNA ribosyltransferase-isomerase resulting in a release of a hydrogen ion, L-methionine, adenine and an epoxyqueuosine"
What is the definition of Selenium Metabolism?,"The selenium metabolism begins with the introduction of selenate and selenite to the cytosol through a sulphate permease system. Once in the cell, selenate can be reduced to selenite through nitrate reductases A and Z. Selenite then interacts with glutathione and 2 hydrogen ions resulting in the release of 2 water molecules, a hydroxide molecule, a glutathione disulfide and a selenodiglutathione. The latter compound then reacts with NADPH+H resulting in the release of a NADP, a glutathione and a glutathioselenol. Glutathiolselenol can then be oxidize resulting in a a glutathiolselenol ion which can then interact with a water molecule resulting in a release of glutathion and seleniumGlutathiolselenol can also react with NADPH and hydrogen ion resulting in a release of glutathione, NADP, a hydroxide molecule and a hydrogen selenide. This compound can react in a reversible reaction by being  oxidized resulting in a hydrogen selenide ion . This compound can then be phosphorylated by interacting with an ATP and releasing a AMP, a phosphate and a selenophosphate."
What is the definition of Curcumin Degradation?,Curcumin is metabolized by being reduced through a NADPH dependent curcumin reductase resulting in a dihydrocurcumin. This compound is then reduced again through a NADPH-dependent dihydrocurcumin reductase resulting in a tetrahydrocurcumin. It is not know yet how this compound enters E.coli
What is the definition of Menaquinol Biosythesis?,"Menaquinol biosynthesis starts with chorismate being metabolized into isochorismate through a isochorismate synthase. Isochorismate then interacts with 2-oxoglutare and a hydrogen ion through a 2-succinyl-5-enolpyruvyl-6-hydroxy-3-cyclohexene-1-carboxylate synthase resulting in the release of a carbon dioxide and a 2-succinyl-5-enolpyruvyl-6-hydroxy-3-cyclohexene-1-carboxylate. The latter compound then interacts with (1R,6R)-2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate synthase resulting in the release of a pyruvate and a (1R,6R)-6-hydroxy-2-succinylcyclohexa-2,4-diene-1-carboxylate. This compound is the dehydrated through a o-succinylbenzoate synthase resulting in the release of a water molecule and a 2-succinylbenzoate. This compound  then interacts with a coenzyme A and an ATP through a o-succinylbenzoate CoA ligase resulting in the release of a diphosphate, a AMP and a succinylbenzoyl-CoA. The latter compound interacts with a hydrogen ion through a 1,4-dihydroxy-2-naphthoyl-CoA synthase resulting in the release of a water molecule or a 1,4-dihydroxy-2-naphthoyl-CoA. This compound then interacts with water through a 1,4-dihydroxy-2-naphthoyl-CoA thioesterase resulting in the release of a coenzyme A, a hydrogen ion and a 1,4-dihydroxy-2-naphthoate.The 1,4-dihydroxy-2-naphthoate can interact with either farnesylfarnesylgeranyl-PP or octaprenyl diphosphate  and a hydrogen ion through a 1,4-dihydroxy-2-naphthoate octaprenyltransferase resulting in a release of a carbon dioxide, a pyrophosphate and a demethylmenaquinol-8. This compound then interacts with SAM through a bifunctional 2-octaprenyl-6-methoxy-1,4-benzoquinone methylase and S-adenosylmethionine:2-DMK methyltransferase resulting in a hydrogen ion, a s-adenosyl-L-homocysteine and a menaquinol."
What is the definition of Glutathione Metabolism II?,"The biosynthesis of glutathione starts with the introduction of L-glutamic acid through either  a glutamate:sodium symporter, glutamate / aspartate : H+ symporter GltP or a glutamate / aspartate ABC transporter. Once in the cytoplasm, L-glutamice acid reacts with L-cysteine through an ATP glutamate-cysteine ligase resulting in gamma-glutamylcysteine. This compound reacts which Glycine through an ATP driven glutathione synthetase thus catabolizing Glutathione.This compound is metabolized through a spontaneous reaction with an oxidized glutaredoxin resulting in a reduced glutaredoxin and an oxidized glutathione. This compound is reduced by a NADPH glutathione reductase resulting in a glutathione. Glutathione can then be degraded into various different glutathione containg compounds by reacting with a napthalene through a glutathione S-transferase"
What is the definition of Flavin Biosynthesis?,"The process of flavin biosynthesis starts with GTP being metabolized by interacting with 3 molecules of water through a GTP cyclohydrolase resulting in a release of formic acid, a pyrophosphate,  two hydrog ions and 2,5-diamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one or 2,5-Diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine. Either of these compounds interacts with a water molecule and a hydrogen ion through a fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in an ammonium and 5-amino-6-(5-phospho-D-ribosylamino)uracil. This compound then interacts with a hydrogen ion through a NADPH dependent fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in the release of a NADP and a 5-amino-6-(5-phospho-D-ribitylamino)uracil. This compound then interacts with a water molecule through a 5-amino-6-(5-phospho-D-ribitylamino)uracil phosphatase resulting in a release of a phosphate, and a 5-amino-6-(D-ribitylamino)uracil.D-ribulose 5-phosphate interacts with a3,4-dihydroxy-2-butanone 4-phosphate synthase resulting in  the release of formic acid, a hydrogen ion and 1-deoxy-L-glycero-tetrulose 4-phosphate.A 5-amino-6-(D-ribitylamino)uracil and 1-deoxy-L-glycero-tetrulose 4-phosphate interact through a 6,7-dimethyl-8-ribityllumazine synthase resulting in the release of 2 water molecules, a phosphate, a hydrogen ion and a 6,7-dimethyl-8-(1-D-ribityl)lumazine.The latter compound then interacts with a hydrogen ion through a riboflavin synthase resulting in the release of a riboflavin and a 5-amino-6-(d-ribitylamino)uracil.The riboflavin is then phosphorylated through an ATP dependent riboflavin kinase resulting in the release of a ADP, a hydrogen ion and a FLAVIN MONONUCLEOTIDE.The flavin mononucleotide interad with a hydrogen ion and an ATP through the riboflavin kinase resulting in the release of a pyrophosphate and Flavin Adenine dinucleotide. This compound is then exported into the periplasm through a FMN/FAD exporter."
What is the definition of Ketogluconate Metabolism?,"The ketogluconate metabolism starts with the degradation of 2,5-didehydro-D-gluconate either  through a NADPH dependent 2,5-diketo-D-gluconate reductase resulting in the release of a NADP and 5-dehydro-D-gluconate or through a NADPH dependent 2,5-diketo-D-gluconate reductase protein complex resulting in the release of a NADP and a 2-keto-L-gulonate. The 2-keto-L-gulonate interacts with a NADPH 2-keto-L-gulonate reductase resulting in a NADP and a L-idonate. The L-idonate interacts with a NADP L-idonate 5-dehydrogenase resulting in the release of hydrogen ion, a NADPH and a 5-dehydro-D-gluconate.The 5-dehydro-D-gluconate interacts with a NADPH driven 5-keto-D-gluconate 5-reductase resulting in the release of a NADP and a D-gluconate.The other way to produce D-gluconate is by having 2,5-Didehydro-D-gluconate interacting with a NADPH and hydrogen ion resulting in the release of a NADP and a 2-keto-D-gluconate which then interact with NADPH a 2-keto-D-gluconate reductase resulting in a NADP and a D-gluconateThe D-gluconate is phosphorylated by an ATP driven D-gluconate kinase resulting in a ADP, a hydrogen ion and a D-gluconate 6-phosphate.This compound can either join the Entner-Doudoroff pathway or be metabolized by a NADP dependent 6-phosphogluconate dehydrogenase resulting in a NADPH, a carbon dioxide and a D-ribulose 5-phosphate.The Entner-doudoroff pathway is dehydrated by a phosphogluconate dehydratase resulting in a water molecule and a 2-dehydro-3-deoxy-D-gluconate 6-phosphate.This compound then interacts with a 2-keto-3-deoxygluconate 6-phosphate aldolase resulting in a D-glyceraldehyde 3-phosphate and a pyruvic acid.The d-glyceraldehyde 3-phosphate is incorporated into a glycolysis while the pyruvic acid is decarboxylated into acetyl CoA"
What is the definition of Glutathione Metabolism III?,"The biosynthesis of glutathione starts with the introduction of L-glutamic acid through either  a glutamate:sodium symporter, glutamate / aspartate : H+ symporter GltP or a glutamate / aspartate ABC transporter. Once in the cytoplasm, L-glutamice acid reacts with L-cysteine through an ATP glutamate-cysteine ligase resulting in gamma-glutamylcysteine. This compound reacts which Glycine through an ATP driven glutathione synthetase thus catabolizing Glutathione.This compound is metabolized through a spontaneous reaction with an oxidized glutaredoxin resulting in a reduced glutaredoxin and an oxidized glutathione. This compound is reduced by a NADPH glutathione reductase resulting in a glutathione. "
What is the definition of Glycolate and Glyoxylate Degradation II?,"Oxaloglycolate (2-Hydroxy-3-oxosuccinate) interacts with a tartrate dehydrogenase resulting in a L-tartrate. L-tartrate then interacts with tartrate dehydrogenase resulting in a Oxaloacetate. Oxaloacetate and acetyl-coa interact  to result in a citrate which is processed by a aconitate hydratase  resulting in a cis-Aconitate and further more into a isocitrate which will eventually be procressed into a glyoxylic acid.  Glyoxylic acid can either be metabolized into L-malic acid by a reaction with acetyl-CoA and Water through a malate synthase G which also releases hydrogen ion and Coenzyme A. L-malic acid is then incorporated into the TCA cycle. Glyoxylic acid can also be metabolized by glyoxylate carboligase, releasing a carbon dioxide and tartronate semialdehyde. The latter compound is then reduced by an NADH driven tartronate semialdehyde reductase 2 resulting in glyceric acid. Glyceric acid is phosphorylated by a glycerate kinase 2 resulting in a 3-phosphoglyceric acid. This compound is then integrated into various other pathways: cysteine biosynthesis, serine biosynthesis and glycolysis and pyruvate dehydrogenase."
What is the definition of D-Sorbitol Degradation II?,"E. coli K-12 can utilize six existing hexitols as source of carbon and energy. Hexitols can enter bacterial cell by specific phosphotransferase system, which is consisted of mannose permease IID component, mannose permease IIC component and PTS system mannose-specific EIIAB component. Sorbitol-6-phosphate will be converted to fructose 6-phosphate by sorbitol-6-phosphate dehydrogenase with cofactor NAD. Sorbitol-6-phosphate will be transformed into β-D-Fructose 6-phosphate spontaneously, which the later product will undergo glycolysis I."
What is the definition of Pyrimidine Ribonucleosides Degradation?,"Cytidine and uridine are transported through their corresponding nucleoside hydrogen symporters. Once cytidine is incorporated into the cytosol, it is deaminated through a reaction with water and a hydrogen ion through a cytidine deaminase resulting in the release of ammonium and uridine. Uridine is then lyased by a phosphate through a uridine phosphorylase resulting in the release of a uracil and an alpha-D-ribose-1-phosphate. This compound is then transformed into an isomer D-ribose 5-phosphate through an alpha-D-ribose 1,5-phosphomutase. This compound is then incorporated into the pentose phosphate pathway."
What is the definition of Oleic Acid Oxidation?,"The process of oleic acid B-oxidation starts with a 2-trans,5-cis-tetradecadienoyl-CoA that can be either be processed by an enoyl-CoA hydratase by interacting with a water molecules resulting in a 3-hydroxy-5-cis-tetradecenoyl-CoA, which can be oxidized in the fatty acid beta-oxidation. On the other hand 2-trans,5-cis-tetradecadienoyl-CoA can become a 3-trans,5-cis-tetradecadienoyl-CoA through a isomerase.  This results interact with a water molecule through a acyl-CoA thioesterase resulting in a hydrogen ion, a coenzyme A and a 3,5-tetradecadienoate"
What is the definition of Uracil Degradation III?,"E. coli is able to utilize pyrimidine nucleosides and bases as the sole source of nitrogen at room temperature. This novel pathway for pyrimidine degradation was discovered by a combination of functional and comparative genomics techniques including high-throughput microarray and phenotype analysis. The pathway depicted here represents a combination of experimental work and functional predictions based on the available evidence.In the presence of a flavin reductase, pyrimidine oxygenase catalyzes the first step in this pathway, the ring opening of uracil at the C4 carbonyl by a novel flavin hydroperoxide-catalyzed mechanism. The initial product of the reaction appears to be (Z)-3-ureidoacrylate peracid, which is unstable and can be slowly reduced to ureidoacrylate. While the RutB enzyme is able to hydrolyze ureidoacrylate, it is thought to hydrolyze peroxyureidoacrylate in vivo, yielding carbamate and (Z)-3-peroxyaminoacrylate. In a spontaneous reaction, carbamate decomposes into one molecule each of ammonia and CO2. The aminoacrylate peracid is thought to be reduced to aminoacrylate by the predicted aminoacrylate peracid reductase. Aminoacrylate can then hydrolyze either spontaneously or enzymatically to 3-oxopropanoate and a second molecule of ammonia. Malonate semialdehyde appears to be toxic and can not be utilized further. The compound may be detoxified by one of two malonic semialdehyde reductases to 3-hydroxypropanoate, which is then excreted into the medium. The toxicity of malonic semialdehyde appears to limit growth on pyrimidines as the sole source of nitrogen. (EcoCyc)"
What is the definition of Phenylethylamine Metabolism?,"The process of phenylethylamine metabolism starts with 2-phenylethylamine interacting with an oxygen molecule and a water molecule in the periplasmic space through a phenylethylamine oxidase. This reaction results in the release of a hydrogen peroxide, ammonium and phenylacetaldehyde. Phenylacetaldehyde is introduced into the cytosol and degraded into phenylacetate by reaction with a phenylacetaldehyde dehydrogenase. This reaction involves phenylacetaldehyde interacting with NAD, and a water molecule and then resulting in the release of NADH, and 2 hydrogen ion.Phenylacetate is then degraded. The first step involves phenylacetate interacting with an coenzyme A and an ATP driven phenylacetate-CoA ligase resulting in the release of a AMP, a diphosphate and a phenylacetyl-CoA. This resulting compound the interacts with a hydrogen ion, NADPH, and oxygen molecule through a ring 1,2-phenylacetyl-CoA epoxidase protein complex resulting in the release of a water molecule, an NADP and a 2-(1,2-epoxy-1,2-dihydrophenyl)acetyl-CoA. This compound is then metabolized by a ring 1,2 epoxyphenylacetyl-CoA isomerase resulting in a 2-oxepin-2(3H)-ylideneacetyl-CoA. This compound is then hydrolated through a oxepin-CoA hydrolase resulting in a 3-oxo-5,6-didehydrosuberyl-CoA semialdehyde. This commpound then interacts with a water molecule and NADP driven 3-oxo-5,6-dehydrosuberyl-CoA semialadehyde dehydrogenase resulting in 2 hydrogen ions, a NADPH and a 3-oxo-5,6-didehydrosuberyl-CoA. The resulting compound interacts with a coenzyme A and a 3-oxo-5,6 dehydrosuberyl-CoA thiolase resulting in an acetyl-CoA and a 2,3-didehydroadipyl-CoA. This resulting compound is the hydrated by a 2,3-dehydroadipyl-CoA hydratas resulting in a 3-hydroxyadipyl-CoA whuch is dehydrogenated through an NAD driven 3-hydroxyadipyl-CoA dehydrogenase resulting in a NADH, a hydrogen ion and a 3-oxoadipyl-CoA. The latter compound then interacts with conezyme A through a beta-ketoadipyl-CoA thiolase resulting in an acetyl-CoA and a succinyl-CoA. The succinyl-CoA is then integrated into the TCA cycle."
What is the definition of Thiamin Diphosphate Biosynthesis?,"The biosynthesis of thiamin begins with a PRPP being degraded by reacting with a water molecule and an L-glutamine through a amidophosphoribosyl transferase resulting in the release of an L-glutamate, a diphosphate and a 5-phospho-beta-d-ribosylamine(PRA). The latter compound, PRA, is further degrade through a phosphoribosylamine glycine ligase by reacting with a glycine and an ATP. This reaction results in the release of a hydrogen ion, an ADP, a phosphate and a N1-(5-phospho-beta-d-ribosyl)glycinamide(GAR). GAR can be metabolized by two different phosphoribosylglycinamide formyltransferase. GAR reacts with a N10-formyl tetrahydrofolate, in this case 10-formyl-tetrahydrofolate mono-L-glutamate, through a phosphoribosylglycinamide formyltransferase 1 resulting in the release of a hydroge ion, a tetrahydrofolate and a N2-formyl-N1-(5-phospho-Beta-D-ribosyl)glycinamide(FGAR). On the other hand, GAR can react with a formate and an ATP molecule through a phosphoribosylglycinamide formyltransferase 2 resulting in a release of a ADP, a phosphate, a hydrogen ion and a FGAR. The FGAR compound gets degraded by interacting with a water molecule, an L-glutamine and an ATP molecule thorugh a phosphoribosylformylglycinamide synthase resulting in the release of a L-glutamate, a phosphate, an ADP molecule, a hydrogen ion and a 2-(formamido)-N1-(5-phopho-Beta-D-ribosyl)acetamidine (FGAM). This compound is further degraded by reacting with an ATP molecule through a phosphoribosylformylglycinamide cyclo-ligase resulting in the release of a phosphate, an ADP, a hydrogen ion and a 5-amino-1-(5-phospho-beta-d-ribosyl)imidazole (AIR).  The AIR molecule is degraded by reacting with a S-adenosyl-L-methionine through a HMP-P synthase resulting in the release of 3 hydrogen ions, a carbon monoxide, a formate molecule, L-methionine, 5'-deoxyadenosine and 4- amino-2-methyl-5-phophomethylpyrimidine (HMP-P). This resulting compound is phosphorylated thorugh a ATP driven phosphohydroxymethylpyrimidine kinase resulting in the release of an ADP and 4-amino-2-methyl-5-diphosphomethylpyrimidine (HMP-PP). The resulting compound interacts with a thiazole tautomer and 2 hydrogen ion through a Thiamine phosphate synthase resulting in the release of a pyrophosphate, a carbon dioxide molecule and Thiamin phosphate. This compound is phosphorylated through an ATP driven thiamin monophosphate kinase resulting in a release of an ADP and a thiamin diphosphate."
"What is the definition of N-Acetylneuraminate, N-Acetylmannosamine, and N-Acetylglucosamine Degradation?","The degradation of N-acetylneuraminate begins with its incorporation into the cytosol through a hydrogen symporter. Once inside the cytosol it is degraded by a N-acetylneuraminate lyase resulting in a release of a pyruvic acid and N-acetymannosamine. The latter compound is phosphorylated by an ATP driven N-Acetylmannosamine kinase resulting in the release of an ADP, a hydrogen ion and a N-Acetyl-D-mannosamine 6-phosphate. This phosphorylated compound is then metabolized by a putative N-acetylmannosamine-6-phosphate 2-epimerase resulting in the release of a N-Acetyl-D-glucosamine 6-phosphate. This compound is then deacetylated through a N-acetylglucosamine-6-phosphate deacetylase resulting in the release of an Acetic acid and a glucosamine 6-phosphate This compound can then be deaminated through a glucosamine-6-phosphate deaminase resulting in the release of an ammonium and a beta-D-fructofuranose 6-phosphate which can then be incorporated into the glycolysis pathway."
What is the definition of Purine Nucleotides De Novo Biosynthesis 2?,"The biosynthesis of purine nucleotides is a complex process that begins with a phosphoribosyl pyrophosphate. This compound interacts with water and L-glutamine through a amidophosphoribosyl transferase resulting in a pyrophosphate, L-glutamic acid and a 5-phosphoribosylamine. The latter compound proceeds to interact with a glycine through an ATP driven phosphoribosylamine-glycine ligase resulting in the addition of glycine to the compound. This reaction releases an ADP, a phosphate, a hydrogen ion and a N1-(5-phospho-β-D-ribosyl)glycinamide. The latter compound interacts with formic acid, through an ATP driven phosphoribosylglycinamide formyltransferase 2 resulting in a phosphate, an ADP, a hydrogen ion and a 5-phosphoribosyl-N-formylglycinamide. The latter compound interacts with L-glutamine, and water through an ATP-driven phosphoribosylformylglycinamide synthetase resulting in a release of a phosphate, an ADP, a hydrogen ion, a L-glutamic acid and a 2-(formamido)-N1-(5-phospho-D-ribosyl)acetamidine. The latter compound interacts with an ATP driven phosphoribosylformylglycinamide cyclo-ligase resulting in a release of ADP, a phosphate, a hydrogen ion and a 5-aminoimidazole ribonucleotide. The latter compound interacts with a hydrogen carbonate through an ATP driven N5-carboxyaminoimidazole ribonucleotide synthetase resulting in a release of a phosphate, an ADP, a hydrogen ion and a N5-carboxyaminoimidazole ribonucleotide.The latter compound then interacts with a N5-carboxyaminoimidazole ribonucleotide mutase resulting in a 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate. This compound interacts with an L-aspartic acid through an ATP driven phosphoribosylaminoimidazole-succinocarboxamide synthase resulting in a phosphate, an ADP, a hydrogen ion and a SAICAR. SAICAR interacts with an adenylosuccinate lyase resulting in a fumaric acid and an AICAR. AICAR interacts with a formyltetrahydrofolate through a AICAR transformylase / IMP cyclohydrolase resulting in a release of a tetrahydropterol mono-l-glutamate and a FAICAR. The latter compound, FAICAR, interacts in a reversible reaction through a AICAR transformylase / IMP cyclohydrolase resulting in a release of water and Inosinic acid. Inosinic acid can be metabolized to produce dGTP and dATP three different methods each. dGTP: Inosinic acid, water and NAD are processed by IMP dehydrogenase resulting in a release of NADH, a hydrogen ion and Xanthylic acid. Xanthylic acid interacts with L-glutamine, and water through an ATP driven GMP synthetase resulting in pyrophosphate, AMP, L-glutamic acid, a hydrogen ion and Guanosine monophosphate. The latter compound is the phosphorylated by reacting with an ATP driven guanylate kinase resulting in a release of ADP and a Gaunosine diphosphate. Guanosine diphosphate can be metabolized in three different ways: 1.-Guanosine diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and a Guanosine triphosphate. This compound interacts with a reduced flavodoxin protein through a ribonucleoside-triphosphate reductase resulting in a oxidized flavodoxin a water moleculer and a dGTP 2.-Guanosine diphosphate interacts with a reduced NrdH glutaredoxin-like proteins through a ribonucleoside-diphosphate reductase 2 resulting in the release of an oxidized NrdH glutaredoxin-like protein, a water molecule and a dGDP. The dGDP is then phosphorylated by interacting with an ATP-driven nucleoside diphosphate kinase resulting in an ADP and dGTP. 3.-Guanosine diphosphate interacts with a reduced thioredoxin ribonucleoside diphosphate reductase 1 resulting in a release of a water molecule, an oxidized thioredoxin and a dGDP. The dGDP is then phosphorylated by interacting with an ATP-driven nucleoside diphosphate kinase resulting in an ADP and dGTP. dATP: Inosinic acid interacts with L-aspartic acid through an GTP driven adenylosuccinate synthase results in the release of GDP, a hydrogen ion, a phosphate and N(6)-(1,2-dicarboxyethyl)AMP. The latter compound is then cleaved by a adenylosuccinate lyase resulting in a fumaric acid and an Adenosine monophosphate. This compound is then phosphorylated by an adenylate kinase resulting in the release of ATP and an adenosine diphosphate. Adenosine diphosphate can be metabolized in three different ways: 1.-Adenosine diphosphate is involved in a reversible reaction by interacting with a hydrogen ion and a phosphate through a ATP synthase / thiamin triphosphate synthase resulting in a hydrogen ion, a water molecule and an Adenosine triphosphate. The adenosine triphosphate interacts with a reduced flavodoxin through a ribonucleoside-triphosphate reductase resulting in an oxidized flavodoxin, a water molecule and a dATP 2.- Adenosine diphosphate interacts with an reduced thioredoxin through a ribonucleoside diphosphate reductase 1 resulting in a release of a water molecule, a oxidized thioredoxin and a dADP. The dADP is then phosphorylated by a nucleoside diphosphate kinase resulting in the release of ADP and a dATP 3.- Adenosine diphosphate interacts with an reduced NrdH glutaredoxin-like protein through a ribonucleoside diphosphate reductase 2 resulting in a release of a water molecule, a oxidized glutaredoxin-like protein and a dADP. The dADP is then phosphorylated by a nucleoside diphosphate kinase resulting in the release of ADP and a dATP "
What is the definition of 2-Oxopent-4-enoate Metabolism 2?,"The pathway starts with trans-cinnamate interacting with a hydrogen ion, an oxygen molecule, and a NADH through a cinnamate dioxygenase resulting in a NAD and a Cis-3-(3-carboxyethyl)-3,5-cyclohexadiene-1,2-diol which then interact together through a 2,3-dihydroxy-2,3-dihydrophenylpropionate dehydrogenase resulting in the release of a hydrogen ion, an NADH molecule and a 2,3 dihydroxy-trans-cinnamate. The second way by which the 2,3 dihydroxy-trans-cinnamate is acquired is through a 3-hydroxy-trans-cinnamate interacting with a hydrogen ion, a NADH and an oxygen molecule through a 3-(3-hydroxyphenyl)propionate 2-hydroxylase resulting in the release of a NAD molecule, a water molecule and a 2,3-dihydroxy-trans-cinnamate. The compound 2,3 dihydroxy-trans-cinnamate then interacts with an oxygen molecule through a 2,3-dihydroxyphenylpropionate 1,2-dioxygenase resulting in a hydrogen ion and a 2-hydroxy-6-oxonona-2,4,7-triene-1,9-dioate. The latter compound then interacts with a water molecule through a 2-hydroxy-6-oxononatrienedioate hydrolase resulting in a release of a hydrogen ion, a fumarate molecule and (2Z)-2-hydroxypenta-2,4-dienoate. The latter compound reacts spontaneously to isomerize into a 2-oxopent-4-enoate. This compound is then hydrated through a 2-oxopent-4-enoate hydratase resulting in a 4-hydroxy-2-oxopentanoate. This compound then interacts with a 4-hydroxy-2-ketovalerate aldolase resulting in the release of a pyruvate, and an acetaldehyde. The acetaldehyde then interacts with a coenzyme A and a NAD molecule through a acetaldehyde dehydrogenase resulting in a hydrogen ion, a NADH and an acetyl-coa which can be incorporated into the TCA cycle"
What is the definition of Secondary Metabolites: Ubiquinol Biosynthesis 2?,"The biosynthesis of ubiquinol starts the interaction of 4-hydroxybenzoic acid interacting with an octaprenyl diphosphate. The former compound comes from the chorismate interacting with a chorismate lyase resulting in the release of a pyruvic acid and a 4-hydroxybenzoic acid. On the other hand, the latter compound, octaprenyl diphosphate is the result of a farnesyl pyrophosphate interacting with an isopentenyl pyrophosphate through an octaprenyl diphosphate synthase resulting in the release of a pyrophosphate and an octaprenyl diphosphate. The 4-hydroxybenzoic acid interacts with octaprenyl diphosphate through a 4-hydroxybenzoate octaprenyltransferase resulting in the release of a pyrophosphate and a 3-octaprenyl-4-hydroxybenzoate. The latter compound then interacts with a hydrogen ion through a 3-octaprenyl-4-hydroxybenzoate carboxy-lyase resulting in the release of a carbon dioxide and a 2-octaprenylphenol. The latter compound interacts with an oxygen molecule and a hydrogen ion through a NADPH driven 2-octaprenylphenol hydroxylase resulting in a NADP, a water molecule and a 2-octaprenyl-6-hydroxyphenol. The 2-octaprenyl-6-hydroxyphenol interacts with an S-adenosylmethionine through a bifunctional 3-demethylubiquinone-8 3-O-methyltransferase and 2-octaprenyl-6-hydroxyphenol methylase resulting in the release of a hydrogen ion, an s-adenosylhomocysteine and a 2-methoxy-6-(all-trans-octaprenyl)phenol. The latter compound then interacts with an oxygen molecule and a hydrogen ion through a NADPH driven 2-octaprenyl-6-methoxyphenol hydroxylase resulting in a NADP, a water molecule and a 2-methoxy-6-all trans-octaprenyl-2-methoxy-1,4-benzoquinol. The latter compound interacts with a S-adenosylmethionine through a bifunctional 2-octaprenyl-6-methoxy-1,4-benzoquinone methylase and S-adenosylmethionine:2-DMK methyltransferase resulting in a s-adenosylhomocysteine, a hydrogen ion and a 6-methoxy-3-methyl-2-all-trans-octaprenyl-1,4-benzoquinol. The 6-methoxy-3-methyl-2-all-trans-octaprenyl-1,4-benzoquinol. interacts with a reduced acceptor, an oxygen molecule through a 2-octaprenyl-3-methyl-6-methoxy-1,4-benzoquinone hydroxylase resulting in the release of a water molecule, an oxidized electron acceptor and a 3-demethylubiquinol-8. The latter compound then interacts with a S-adenosylmethionine through a bifunctional 3-demethylubiquinone-8 3-O-methyltransferase and 2-octaprenyl-6-hydroxyphenol methylase resulting in a hydrogen ion, a S-adenosylhomocysteine and a ubiquinol 8."
What is the definition of L-Carnitine Degradation I?,"L-Carnitine can stimulate anaerobic growth of E.coli when exogenous electron acceptors (i.e. nitrate, etc.) are absent. During anaerobic growth, E.coli can reduce L-carnitine to γ-butyrobetaine by CoA-linked intermediates when carbon and nitrogen are present in the system. Therefore, L-carnitine may act as external electron acceptor for anaerobic growth as well as generation of an osmoprotectant for cell."
What is the definition of D-Arabinose Degradation I?,"Wild-Type E.coli K-12 can not directly use D-arabinose as a sole source of carbon and energy; hence, E.coli uses the enzymes of the fucose degradation pathway to degrade D-arabinose for further utilization. D-arabinose can be metabolized to form dihydroxy-acetone phosphate for entering the central metabolism. Glycolaldehyde can be further catalyzed to form glycolic acid by lactaldehyde dehydrogenase."
What is the definition of Aminopropylcadaverine Biosynthesis?,"Aminopropylcadaverine, a polyamine, is the final product of aminopropylcadaverine biosynthesis pathway. Polyamines are involved in protein synthesis, DNA and RNA related processes, as well as the facilitation of cell stress resistance and membrane integrity; therefore polyamines are essential for cell growth. In this pathway, L-lysine is produced by lysine biosynthesis, then lysine decarboxylase will convert L-lysine into cadaverine. In the final step, spermidine synthase will catalyze cadaverine and decarboxy-SAM to aminopropylcadaverine as well as 5'-Methylthioadenosine. "
What is the definition of Spermidine Biosynthesis I?,"Spermidine is formed from decarboxy-SAM and putrescine by catalyzing spermidine synthase (also knowns as polyamine aminopropyltransferase). The source of putrescine is transported from outside of cell by putrescine/spermidine ABC transporter. Decarboxy-SAM comes from S-Adenosylmethionine with catalyzation of adenosylmethionine decarboxylase and cofactors: pyruvic acid and magnesium. The other product of the aminopropyltransferase reaction is S-methyl-5'-thioadenosine (MTA), which can be recycled back to L-methionine in many organisms, but not in E. coli. Inhibition of E. coli adenosylmethionine decarboxylase by spermidine appears to be the most significant regulator of polyamine biosynthesis, probably limiting it when the intracellular spermidine concentration becomes excessive. In E. coli most intracellular spermidine is bound to nucleic acids and phospholipids. (EcoCyc)"
What is the definition of Thiazole Biosynthesis I ?,"This pathway demonstrate the biosynthesis of thiazole moiety in E.coli K-12 strain and Salmonella enterica serovar Typhimurium. L-Tyrosine is generated from tyrosine biosynthesis. With S-Adenosylmethionine and NADPH, L-Tyrosine can be catalyzed into four different small molecules: 4-methylcatechol, dehydroglycine, 5'-deoxyadenosine and L-methionine as well as NADP by dehydroglycine synthase (encoded by thiH gene). Meanwhile, 1-deoxyxylulose-5-phosphate synthase (encoded by dxs gene) catalyzes pyruvic acid and D-Glyceraldehyde 3-phosphate into 1-Deoxy-D-xylulose 5-phosphate. The final reaction of the pathway is facilitated by thiazole synthase (encoded by thiG and thiH), which require a thiocarboxy-[ThiS-Protein], 1-deoxy-D-xylulose 5-phosphate and 2-iminoacetate to form 2-((2R,5Z)-2-Carboxy-4-methylthiazol-5(2H)-ylidene)ethyl phosphate for Thiamin Diphosphate Biosynthesis, as well as a ThiS sulfur-carrier protein and water."
What is the definition of Chitobiose Degradation?,"Diacetylchitobiose (also known as N,N'-diacetylchitobiose and chitobiose) is a sole source of carbon for E.coli. PTS system mannitol-specific EIICBA component facilitates the imports of diacetylchitobiose as well as the phosphorylation to diacetylchitobiose 6'-phosphate. Later on, diacetylchitobiose 6'-phosphate is hydrolyzed to N-monoacetylchitobiose 6'-phosphate, which also produce acetic acid. N-monoacetylchitobiose 6'-phosphate undergoes further hydrolyzation to form N-Acetyl-D-Glucosamine 6-Phosphate and glucosamine by monoacetylchitobiose-6-phosphate hydrolase. "
What is the definition of Tetrahydromonapterin Biosynthesis?,"This pathway demonstrates the biosynthesis of tetrahydromonapterin in E.coli. However, it is still unclear about biological role of tetrahydromonapterin. GTP cyclohydrolase 1 generates formic acid and 7,8-dihydroneopterin 3'-triphosphate with cofactor GTP and water. 7,8-dihydroneopterin 3'-triphosphate is converted to dihydromonapterin-triphosphate by d-erythro-7,8-dihydroneopterin triphosphate epimerase (folX). Later, dihydromonapterin-triphosphate is hydroxylated to dihydromethysticin, and eventually form tetrahydromonapterin via dihydromonapterin reductase (folM) with cofactor NADPH."
What is the definition of Palmitate Biosynthesis 2?,"Palmitate is synthesized by stepwise condensation of C2 units to a growing acyl chain. Each elongation cycle results in the addition of two carbons to the acyl chain, and consists of four separate reactions. The pathway starts with acetyl-CoA interacting with hydrogen carbonate through an ATP driven acetyl-CoA carboxylase resulting in a phosphate, an ADP , a hydrogen ion and a malonyl-CoA. The latter compound interacts with a holo-[acp] through a malonyl-CoA-ACP transacylase resulting in a CoA and a malonyl-[acp]. This compound interacts with hydrogen ion, acetyl-CoA through a KASIII resulting in a CoA, carbon dioxide and an acetoacetyl-[acp]. The latter compound interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxybutanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a crotonyl-[acp](2). The crotonyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a butyryl-[acp](3). The butyryl-[acp] interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-hexanoyl-[acp](4). The 3-oxo-hexanoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxyhexanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans hex-2-enoyl-[acp](2). The trans hex-2-enoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a hexanoyl-[acp](3). The hexanoyl-[acp] interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-octanoyl-[acp](4). The 3-oxo-octanoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxyoctanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans oct-2-enoyl-[acp](2). The trans oct-2-enoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a octanoyl-[acp](3). The octanoyl-[acp] interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-decanoyl-[acp](4). The 3-oxo-decanoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxydecanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans-delta2-decenoyl-[acp](2). The a trans-delta2-decenoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a decanoyl-[acp](3). The decanoyl-[acp] interacts with a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-dodecanoyl-[acp](4). The 3-oxo-dodecanoyl-[acp ]interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (R) 3-Hydroxydodecanoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans dodec-2-enoyl-[acp](2). The trans dodec-2-enoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a dodecanoyl-[acp](3). This compound can either react with water spontaneously resulting in a hydrogen ion, a holo-[acp] and a dodecanoic acid or it interacts with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-myristoyl-[acp](4). The 3-oxo-myristoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (3R) 3-Hydroxymyristoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans tetradec-2-enoyl-[acp](2). This compound interacts with a hydrogen ion, through a NADH-driven KASI resulting in a NAD and a myristoyl-[acp]. Myristoyl-[acp] with a hydrogen ion, a malonyl-[acp] through a KASI resulting in a holo-[acp],carbon dioxide and a 3-oxo-palmitoyl-[acp](4). The 3-oxo-palmitoyl-[acp] interacts with a hydrogen ion through a NADPH driven 3-oxoacyl-[acyl-carrier-protein] reductase resulting in an NADP and a (3R) 3-Hydroxypalmitoyl-[acp](1). This compound is then dehydrated by a 3-hydroxyacyl-[acyl-carrier-protein] dehydratase resulting in the release of water and a trans hexadecenoyl-[acp](2). The trans hexadecenoyl-[acp] interacts with a hydrogen ion through a NADH enoyl-[acyl-carrier-protein] reductase(NAD) resulting in NAD and a palmitoyl-[acp](3). Palmitoyl then reacts with water spontaneously resulting in a hydrogen ion, a holo-[acp] and palmitic acid. No integral membrane protein required for long chain fatty acid uptake has been identified in E. coli. The transport of long chain fatty acids across the cytoplasmic membrane is dependent on fatty acyl-CoA synthetase. An energised membrane is necessary for fatty acid transport and it has been suggested that uncharged fatty acids flip across the inner membrane by diffusion."
What is the definition of Enterobactin Biosynthesis?,"Enterobactin (also known as Enterochelin) is produced by enterobacteria such as Escherichia coli and Salmonella typhimurium. Under iron-deficient condtion, enterobactin can be synthesized and excreted into environment to bind Fe(III). Chorismate is the starting compound for enterobactin biosynthesis, and it can be obtained from chorismate biosynthesis pathway. Isochorismate synthase catalyzes chorismate to form isochorismate, and further breaking down to form (2S,3S)-2,3-dihydroxy-2,3-dihydrobenzoate and pyruvic acid by same synthase enzyme. (2S,3S)-2,3-dihydroxy-2,3-dihydrobenzoate is converted to 2,3-Dihydroxybenzoic acid by 2,3-dihydro-2,3-dihydroxybenzoate dehydrogenase. The later synthesis of enterobactin is catalyzed from 2,3-dihydroxybenzoate and L-serine."
What is the definition of Fructoselysine and Psicoselysine Degradation?,"Fructosamines are compounds that result from glycation reactions between a sugar and a primary amine, followed by isomerization via the Amadori rearrangement. In fructoselysine degradation, fructoselysine firstly converts to 1-[(5-Amino-5-carboxypentyl)amino]-1-deoxyfructose by protein frlC, and then 1-[(5-Amino-5-carboxypentyl)amino]-1-deoxyfructose is transformed to fructoselysine-6-phosphate by fructoselysine kinase which is powered by ATP. Fructoselysine-6-phosphate finally degrades to β-D-Glucose 6-phosphate and L-lysine by fructoselysine 6-phosphate deglycase. "
What is the definition of Allantoin Degradation (Anaerobic)?,"Allantoin can be degraded in anaerobic conditions. The first step involves allantoin being degraded by an allantoinase resulting in an allantoate. This compound in turn is metabolized by reacting with water and 2 hydrogen ions through an allantoate amidohydrolase resulting in the release of a carbon dioxide, ammonium and an S-ureidoglycine. The  latter compund is further degrades through a S-ureidoglycine aminohydrolase resulting in the release of an ammonium and an S-ureidoglycolate. S-ureidoglycolate can be metabolized into oxalurate by two different reactions. The first reactions involves a NAD driven ureidoglycolate dehydrogenase resulting in the release of a hydrogen ion , an NADH and a oxalurate. On the other hand S-ureidoglycolate can react with NADP resulting in the release of an NADPH, a hydroge ion and an oxalurate.It is hypothesized that oxalurate can interact with a phosphate and release a a carbamoyl phosphate and an oxamate.The carbamoyl phosphate can be further degraded by reacting with an ADP, and a hydrogen ion through a carbamate kinase resulting in the release of an ammonium , ATP and carbon dioxide"
What is the definition of Polymyxin Resistance?,"UDP-glucuronic acid compound undergoes a NAD dependent reaction through a bifunctional polymyxin resistance protein to produce UDP-Beta-L-threo-pentapyranos-4-ulose. This compound then reacts with L-glutamic acid through a UDP-4-amino-4-deoxy-L-arabinose--oxoglutarate aminotransferase to produce an oxoglutaric acid and UDP-4-amino-4-deoxy-beta-L-arabinopyranose The latter compound interacts with a N10-formyl-tetrahydrofolate through a bifunctional polymyxin resistance protein ArnA, resulting in a tetrahydrofolate, a hydrogen ion and a UDP-4-deoxy-4-formamido-beta-L-arabinopyranose, which in turn reacts with a product of the methylerythritol phosphate and polysoprenoid biosynthesis pathway, di-trans,octa-cis-undecaprenyl phosphate to produce a 4-deoxy-4-formamido-alpha-L-arabinopyranosyl ditrans, octacis-undecaprenyl phosphate. The compound  4-deoxy-4-formamido-alpha-L-arabinopyranosyl ditrans, octacis-undecaprenyl phosphate hypothetically reacts with water and results in the release of a formic acid and  4-amino-4-deoxy-α-L-arabinopyranosyl ditrans,octacis-undecaprenyl phosphate which in turn reacts with a KDO2-lipid A through a 4-amino-4-deoxy-L-arabinose transferase resulting in the release of a di-trans,octa-cis-undecaprenyl phosphate and a L-Ara4N-modified KDO2-Lipid A"
What is the definition of Superoxide Radicals Degradation?,"In gram-negative bacteria, cytoplasmic and periplasmic isozymes of superoxide dismutase (SOD) is their defense system against superoxide anion (O2-). In E.coli, there are several SOD isozymes which are manganese-cofactored (MnSOD), iron-cofactored (FeSOD) and copper, zinc-cofactored (CuZnSOD) in perplasm, and they can be generated by autooxidation of dihydromenaquinone in the cytoplasmic membrane. In E.coli, MnSOD and FeSOD have similar structure and kinetic, but CuZnSOD is monomeric. FeSOD is the only SOD in E.coli under anaerobic conditions. MnSOD is induced by environmental stress condition as well as aerobic growth. CuZnSOD is induced in stationary phase. SOD will catalyze the superoxide anion to form oxygen and H2O2. With increasing concentration of H2O2, catalase such as cryptic adenine deaminase is induced in E.coli to degrade H2O2 into water and oxygen."
What is the definition of Putrescine Degradation II?,"This pathway demonstrates the degradation of extracellular putrescine in E.coli. Putrescine is imported by putrescine transporter (encoded by puuP gene). Putrescine is γ-glutamylated by activation of ATP which generates γ-glutamyl-putrescine, phosphate, and ADP. γ-glutamyl-putrescine is oxidized by gamma-glutamylputrescine oxidoreductase to form γ-glutamyl-γ-butyraldehyde, also produce ammonium and water. Gamma-glutamyl-gamma-aminobutyraldehyde dehydrogenase dehydrogenates γ-glutamyl-γ-butyraldehyde to γ-glutamyl-γ-aminobutyrate, which is then dehydrogenated into γ-Aminobutyric acid and L-Glutamic acid by γ-glutamyl-γ-aminobutyrate hydrolase. "
What is the definition of Propanoyl-CoA Degradation?,"The degradation of propanoyl-CoA starts with propanoyl-CoA undergoing a decarboxylase reaction by reacting with hydrogen carbonate and ATP resulting in the release of a phosphate, an ADP, a hydrogen ion and an S-methylmalonyl-CoA. This compound in turn reacts through an epimerase reaction resulting in the release of a R-methylmalonyl-CoA. This compound in turn can undergo a reversible reaction through a methylmalonyl-CoA mutase resulting in the release of a succinyl-CoA. This compound can be converted back to R-methylmalonyl-CoA through a methylmalonyl-CoA mutase. Methylmalonyl-CoA can then be converted into propanoyl-CoA through a methylmalonyl CoA decarboxylase . This compound in turn reacts with a succinate through a propionyl-CoA succinate CoA transferase resulting in the release of a propanoate and a succinyl-CoA."
What is the definition of Conversion of Succinate to Propanoate?,"The enzymes involved in the decarboxylation of succinate to propionate are encoded in the Escherichia coli operon.  A CoA transferase reaction is catalyzed by YgfH with succinyl CoA and propionyl CoA donating and succinate and propionate accepting. Sbm, sleeping beauty mutase or methylmalonyl-CoA mutase, is an apoenzyme that is activated by binding of adenosylcobalamin. Sbm catalyzes the methylmalonyl CoA mutase reaction. The metabolic function if this pathway is still unknown."
What is the definition of Thiosulfate Disproportionation III?,"Thiosulfate sulfurtransferase (also known as rhodanese) can facilitate the transfer of a sulfur atom from sulfur donors to nucleophilic sulfur acceptors, and it has been found in many major phyla (prokaryotic and eukaryotic). The role of thiosulfate sulfurtransferase might be the detoxification of cyanide in both bacteria and mammals, or it might also involve in formation of prosthetic groups in iron-sulfur proteins. In this pathway, thiosulfate and hydrogen cyanide have been catalyzed by thiosulfate sulfurtransferase to form thiocyanate and sulfite. Sulfite is used in later sulfur metabolism."
What is the definition of Salvage Pathways of Pyrimidine Deoxyribonucleotides?,"The pathway begins with the introduction of deoxycytidine into the cytosol, either through a nupG symporter or a nupC symporter. Once inside it is deaminated when reacting with a water molecule, a hydrogen ion and a deoxycytidine deaminase resulting in the release of an ammonium and a deoxyuridine. Deoxyuridine can also be imported through a nupG symporter or a nupC symporter. Deoxyuridine can react with an ATP through a deoxyuridine kinase resulting in the release of a ADP , a hydrogen ion and a dUMP.Deoxyuridine can also react with a phosphate through a uracil phosphorylase resulting in the release of a uracil and a deoxy-alpha-D-ribose 1-phosphate. This compound in turn reacts with a thymine through a thymidine phosphorylase resulting in the release of a phosphate and a thymidine. Thymidine in turn reacts with an ATP through a thymidine kinase resulting in a release of an ADP, a hydrogen ion and a dTMP "
What is the definition of Peptidoglycan Biosynthesis II?,"Peptidoglycan is a net-like polymer which surrounds the cytoplasmic membrane of most bacteria and functions to maintain cell shape and prevent rupture due to the internal turgor.In E. coli K-12, the peptidoglycan consists of glycan strands of alternating subunits of N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc) which are cross-linked by short peptides. The pathway for constructing this net involves two cell compartments: cytoplasm and periplasmic space. The pathway starts with a beta-D-fructofuranose going through a mannose PTS permease, phosphorylating the compund and producing a beta-D-fructofuranose 6 phosphate. This compound can be obtained from the glycolysis and pyruvate dehydrogenase or from an isomerization reaction of Beta-D-glucose 6-phosphate through a glucose-6-phosphate isomerase.The compound Beta-D-fructofuranose 6 phosphate and L-Glutamine react with a glucosamine fructose-6-phosphate aminotransferase, thus producing a glucosamine 6-phosphate and a l-glutamic acid. The glucosamine 6-phosphate interacts with phosphoglucosamine mutase in a reversible reaction producing glucosamine-1P. Glucosamine-1p and acetyl coa undergo acetylation throuhg a bifunctional protein glmU releasing Coa and a hydrogen ion and producing a N-acetyl-glucosamine 1-phosphate. Glmu, being a bifunctional protein, follows catalyze the interaction of N-acetyl-glucosamine 1-phosphate, hydrogen ion and UTP into UDP-N-acetylglucosamine and pyrophosphate. UDP-N-acetylglucosamine then interacts with phosphoenolpyruvic acid and a UDP-N acetylglucosamine 1- carboxyvinyltransferase realeasing a phosphate and the compound UDP-N-acetyl-alpha-D-glucosamine-enolpyruvate. This compound undergoes a NADPH dependent reduction producing a UDP-N-acetyl-alpha-D-muramate through a UDP-N-acetylenolpyruvoylglucosamine reductase. UDP-N-acetyl-alpha-D-muramate and L-alanine react in an ATP-mediated ligation through a UDP-N-acetylmuramate-alanine ligase releasing an ADP, hydrogen ion, a phosphate and a UDP-N-acetylmuramoyl-L-alanine. This compound interacts with D-glutamic acid and ATP through UDP-N-acetylmuramoylalanine-D-glutamate ligase releasing ADP, A phosphate and UDP-N-acetylmuramoyl-L-alanyl-D-glutamate. The latter compound then interacts with meso-diaminopimelate in an ATP mediated ligation through a UDP-N-acetylmuramoylalanine-D-glutamate-2,6-diaminopimelate ligase resulting in ADP, phosphate, hydrogen ion and UDP-N-Acetylmuramoyl-L-alanyl-D-gamma-glutamyl-meso-2,6-diaminopimelate. This compound in turn with D-alanyl-D-alanine react in an ATP-mediated ligation through UDP-N-Acetylmuramoyl-tripeptide-D-alanyl-D-alanine ligase to produce UDP-N-acetyl-alpha-D-muramoyl-L-alanyl-gama-D-glutamyl-meso-2,6-diaminopimeloyl-Dalanyl-D-alanine and hydrogen ion, ADP, phosphate. UDP-N-acetyl-alpha-D-muramoyl-L-alanyl-gama-D-glutamyl-meso-2,6-diaminopimeloyl-Dalanyl-D-alanine interacts with di-trans,octa-cis-undecaprenyl phosphate through a phospho-N-acetylmuramoyl-pentapeptide-transferase, resulting in UMP and N-Acetylmuramoyl-L-alanyl-D-glutamyl-meso-2,6-diaminopimelyl-D-alanyl-D-alanine-diphosphoundecaprenol which in turn reacts with a UDP-N-acetylglucosamine through a N-acetylglucosaminyl transferase to produce a hydrogen, UDP and Undecaprenyl-diphospho-N-acetylmuramoyl-(N-acetylglucosamine)-L-alanyl-D-glutaminyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine. This compound ends the cytoplasmic part of the pathway. Undecaprenyl-diphospho-N-acetylmuramoyl-(N-acetylglucosamine)-L-alanyl-D-glutaminyl-meso-2,6-diaminopimeloyl-D-alanyl-D-alanine is transported through a lipi II flippase. Once in the periplasmic space, the compound reacts with a penicillin binding protein 1A prodducing a peptidoglycan dimer, a hydrogen ion, and UDP. The peptidoglycan dimer then reacts with a penicillin binding protein 1B producing a peptidoglycan with D,D, cross-links and a D-alanine."
What is the definition of Pyrimidine Deoxyribonucleosides Degradation?,"The degradation of deoxycytidine starts with deoxycytidine being introduced into the cytosol through either a nupG or nupC symporter. Once inside, it can can be degrade through water,a hydrogen ion and a deoxycytidien deaminsa resultin in the release of a ammonium and a a deoxyuridine. The deoxyuridine is then degraded through a uracil phosphorylase resulting in the release of a deoxyribose 1-phosphate and a uracil.The degradation of thymidine starts with thymidine being introduced into the cytosol through either a nupG or nupC symporter. Thymidine is then degrades through a phosphorylase resulting in the release of a thymine and a deoxyribose 1-phosphate."
"What is the definition of 1,6-Anhydro-N-acetylmuramic Acid Recycling?","Most bacteria, including Escherichia coli, are composed of murein which protects and stabilizes the cell wall. Over half of the murein is broken down by Escherichia coli and recycled for the next generation. The main muropeptide is GlcNAc-anhydro-N-acetylmuramic acid (anhMurNAc)-l-Ala-γ-d-Glu-meso-Dap-d-Ala which enters the cytoplasm by AmpG protein. The peptide is then released from the muropeptide. 1,6-Anhydro-N-acetylmuramic acid (anhMurNAc) is recycled by its conversion to N-acetylglucosamine-phosphate (GlcNAc-P). The sugar is phosphorylated by anhydro-N-acetylmuramic acid kinase (AnmK) to produce MurNAc-P. Etherase cleaves MurNAc-P to produce N-acetyl-D-glucosamine 6-phosphate. The product can undergo further degradation or be recycled into peptidoglycan monomers. The pathway's final product is a peptidoglycan biosynthesis precursor, UDP-N-acetyl-α-D-muramate. The enzyme muropeptide ligase (mpl), attaches the recovered Ala-Glu-DAP tripeptide to the precursor UDP-N-acetyl-α-D-muramate to return to the peptide to the peptidoglycan biosynthetic pathway to synthesize the cell wall. "
What is the definition of Methylphosphonate Degradation I?,"The pathway of methylphosphonate degradation starts with methylphosphonate being degrade by an ATP driven methylphosphonate degradation complex resulting in a alpha-D-ribose-1-methylphosphonate-5-triphosphate. This compound in turn is degraded by a water driven RPnTP hydrolase resulting in the release of a hydrogen ion, a pyrophosphate and a alpha-Dribose-1-methylphosphonate 5-phosphate. The latter compound is then involved with a carbon-phosphorous lyase resulting in the release of a methane and a 5-phospho-alpha-D-ribose 1,2-cyclic phosphate. This compound in turn gets degraded by a water driven 5-phospho-alpha-D-ribosyl 1,2-cyclic phosphate phosphodiesterase resulting in the release of a hydrogen ion and a alpha-D-ribose 1,5-biphosphate."
What is the definition of Hydrogen Sulfide Biosynthesis I?,"Many bacteria can produce hydrogen sulfide, which can be used as defense system against antibiotics and oxidative stress. This pathway is one of the hydrogen sulfide biosynthesis pathways (totally two). L-Cysteine is transported by L-cysteine ABC transporter and convert to 3-mercaptopyruvic acid by facilitation of aspartate aminotransferase. 3-Mercaptopyruvic acid is later catalyzed to form pyruvic acid and hydrogen sulfide by 3-mercaptopyruvate sulfurtransferase. "
What is the definition of Biotin-Carboxyl Carrier Protein Assembly?,"The assembly of a biotin-carboxyl carrier protein starts with a biotin carboxyl carrier protein monomer interacting with an ATP, and a biotin through a biotin -acetyl-coa-carboxylase ligase resulting in the release of a hydrogen ion, an AMP, a diphosphate and a biotynylated BCCP monomer. The latter compound reacts spontaneously to create a biotinylated BCCP dimer. This compound in turn reacts with a hydrogen carbonate and an ATP driven biotin carboxylase resulting in the release of ADP, a hydrogen Ion , a phosphate and a carboxylated biotinylated BCCP dimer.This complex can be degraded by reacting with water, an acetyl0CoA, and an ATP driven acetyl-CoA carboxyltransferase resulting in the release of a hydrogen ion, a phosphate, an ADP, a malonyl-CoA and a biotynylated BCCP dimer"
What is the definition of 4-Aminobutanoate Degradation I?,"E. coli can utilize putrescine as the sole source of carbon and nitrogen. The enzymes of the putrescine degradation II pathway are inducible by extracellular putrescine, leading to the production of GABA. Both enzymes of this pathway are inducible by putrescine in E. coli.This variant of the pathway includes a 2-oxoglutarate-dependent 4-aminobutyrate transaminase and an NAD+-dependent dehydrogenase. This combination of enzymes has been documented in bacteria and animals and in some plants.Regarding the hydrogenase, NAD-specific variants have been studied from many bacteria, plant and animals."
What is the definition of Adenine and Adenosine Salvage I?,"The salvage of adenine begins with adenine being transporter into the cytosol through a adeP hydrogen symporter. Once in the cytosol adenine is degraded by reacting with a ribose-1-phosphate through an adenosine phosphorylase resulting in the release of a phosphate and adenosine. Adenosine is then deaminated by reacting with water, a hydrogen ion and an adenosine deaminase resulting in the release of an ammonium and a inosine . Inosine then reacts with a phosphate through a inosine phosphorylase resulting in the release of a ribose 1-phosphate and a hypoxanthine. Hypoxanthine reacts with a PRPP through a hypoxanthine phosphoribosyltransferase resulting in the release of a pyrophosphate and a IMP molecule."
What is the definition of Adenine and Adenosine Salvage II?,"The salvage of adenine begins with adenine being transporter into the cytosol through a adeP hydrogen symporter. Once in the cytosol adenine is degraded by reacting with a ribose-1-phosphate through an adenosine phosphorylase resulting in the release of a phosphate and adenosine. Adenosine is then deaminated by reacting with water, a hydrogen ion and an adenosine deaminase resulting in the release of an ammonium and a inosine . Inosine can then be phosphorylated through an ATP driven inosine kinase resulting in the release of an ADP, a hydrogen ion and a IMP"
What is the definition of Adenine and Adenosine Salvage III?,"Adenosine is first incorporated into the cytosol through either a nupG or a nupC transporter. Once in the cytosol, adenosine is degraded into adenine by reacting with a water and a adenosine nucleosidase, releasing a D-ribofuranose and a adenine. The adenine then reacts with a PRPP through a adenine phosphoribosyltransferase resulting in the release of a pyrophosphate and an AMP . The AMP in turn reacts with a water molecule through a AMP nucleosidase resulting in the release of a D-ribofuranose 5-phosphate and a adenine."
What is the definition of L-Lactaldehyde Degradation (Aerobic)?,(S)-lactaldehyde is derived from degradation of L-fucose and rhamnose. (S)-lactaldehyde is converted to lactic acid by lactaldehyde dehydrogenase with NAD as cofactor. L-lactate dehydrogenase dehydrogenates lactic acid to pyruvic acid for the pathway of glycolysis and pyruvate dehydrogenase.
What is the definition of Guanine and Guanosine Salvage?,"Guanosine can be converted into guanine through a phosphate driven guanosine phosphorylase resulting in the release of an alpha-D-ribose 1 phosphate and a guanine. This compound in turn reacts with a PRPP through a guanine phosphoribosyltransferase resulting in the release of a pyrophosphate and a GMP.Guanosine can also react with and ATP driven guanosine kinase resulting in the release of an ADP, s hydrogen ion and a GMP"
What is the definition of Citrate Lyase Activation?,"The citrate lyase activation starts with a 3-dephospho-CoA  reacting with ATP and a hydrogen ion through a triphosphoribosyl-dephospho-CoA synthase resulting in a adenine and a 2'-(5'-triphospho-alpha-D-ribosyl)-3'-dephospho-CoA. The latter compound in turn reacts with with a citrate lyase acyl-carrier protein through a apo-citrate lyase phosphoribosyl-dephospho-CoA transferase resulting in the release of a pyrophosphate and a hydrogen ion and a holo citrate lyase acyl-carrier protein.This  protein complex can either react with a hydrogen ion and a acetate resulting in the release of a water and an acetyl-holo citrate lyase acyl-carrier protein.The holo acyl-carrier protein creacts with an ATP and an acetate through a citrate lyase synthase resulting in the release of an AMP, a pyrophosphate and an acetyl-holo citrate lyase acyl-ccarrier protein. The holo citrate lyase acyl-carrier protein can also interact with an S-acetyl phosphopantethiene resulting in the release of a  4-phosphopantethiene and an acetyl-holo citrate lyase acyl-carrier protein."
What is the definition of Purine Ribonucleosides Degradation?,"Purine ribonucleoside degradation leads to the production of alpha-D-ribose-1-phosphate.Xanthosine is transported into the cytosol through a xapB. Once in the cytosol xanthosine interacts with phosphate through a xanthosine phosphorylase resulting in the release of a xanthine and a alpha-D-ribose-1-phosphate.Adenosine is transported through a nupC or a nupG transporter, once inside the cytosol it can either react with a phosphate through a adenosine phosphorylase resultin in the release of a adenine and an alpha-D-ribose-1-phosphate. Adenosine reacts with water and hydrogen ion through a adenosine deaminase resulting in the release of ammonium and inosine. Inosine reacts with phosphate through a inosine phosphorylase resulting in the release of a hypoxanthine and an alpha-D-ribose-1-phosphate.Guanosine reacts with a phosphate through a guanosine phosphorylase resulting in the release of a guanine and a alpha-D-ribose-1-phosphate."
What is the definition of Purine Deoxyribonucleosides Degradation?,"The purine deoxyribonucleosides degradation starts with deoxyadenosine reacting with a water molecule and a hydrogen in through a deoxyadenosune deaminase resulting in the release of ammonium and a deoxyinosine. Deoxyinosine reacts in a reversible manner with phosphate  through a deoxyinosine phosphorylase  resulting in the release of a hypoxanthine and a 2-deoxy-alpha-D-ribose-1-phosphate. Deoxyadenosine reacts with a phosphate through a deoxyadenosine phosphorylase resulting in the release of adenine and a 2-deoxy-alpha-D-ribose-1-phosphate. This compound in turn reacts with guanine through a deoxyguanosine phosphorylase resulting in the release of a phosphate and a deoxyguanosine. Deoxy-alpha-D-ribose 1-phosphate reacts with a deoxyribose 1,5-phosphomutase resulting in the release of a 2-deoxy-D-ribose 5 phosphate. This compound in turn reacts with deoxyribose-phosphate aldolase resulting in the release of an acetaldehyde and a a D-glyceraldehyde 3-phosphate."
What is the definition of Methylglyoxal Degradation IV?,"In this pathway, which has been characterized in Escherichia coli K-12, methylglyoxal is reduced to lactaldehyde by the enzyme methylglyoxal reductase. (S)-lactaldehyde is then reduced to (S)-lactate which is finally converted to pyruvate and joins the pool of central metobolites.Methylglyoxal reductases have been characterized in bacteria and fungi. Some of the enzymes are NADP-linked, while others are NAD-linked. Two variants of this pathway have been entered in MetaCyc to reflect the different biochemistry of the last enzyme, L-lactate dehydrogenase. The Escherichia coli K-12 enzyme encoded by gene lldD uses an unidentified electron acceptor, while the Saccharomyces cerevisiae enzyme uses an an oxidized c-type cytochrome. (EcoCyc)"
What is the definition of Methylglyoxal Degradation III?,"In E. coli there are several pathways for the removal of methylglyoxal. In this pathway, methylglyoxal is reduced to acetol by the action of various enzymes possessing methylglyoxal reductase activity. Most of the enzymes that have been characterized with this activity belong to the NADPH-dependent aldo-keto reductase subfamily of the aldo-keto reductase (AKR) superfamily. AKRs are found in both prokaryotes and eukaryotes and catalyze the reduction of carbonyl-containing aldehyde and/or ketone containing compounds to their corresponding alcohols. A few dual-specificity AKRs are also able to utilize NADH. An AKR from E. coli has been identified that is NADH-specific (AKR11B2, the product of gene ydjG). AKRs have been of considerable interest in metabolic engineering studies.E. coli K-12 enzymes homologous to mammalian AKRs have been shown to catalyze the methylglyoxal reductase reaction. Overexpression of the aldo-keto reductase AKR14A1, encoded by the yghZ gene, leads to increased resistance to methylglyoxal. In addition, three other genes yeaE (yeaE), dkgA (yqhE), and dkgB (yafB) were shown to encode proteins with similar activities. All four proteins were purified, and shown to catalyze the reaction in vitro, in the presence of NADPH.Prolonged incubation of E. coli cell-free extracts with methylglyoxal resulted in conversion of acetol to (S)-propane-1,2-diol. The enzyme proposed to catalyze (S)-propane-1,2-diol production is L-1,2-propanediol dehydrogenase / glycerol dehydrogenase. In bacteria (S)-propane-1,2-diol is a dead-end metabolite and exits the cell rapidly.Although AKRs can reduce methylglyoxal to acetol, a methylglyoxal reductase (NADPH-dependent) encoded by an unknown gene was purified from E. coli and shown to convert methylglyoxal to lactaldehyde. (EcoCyc)"
What is the definition of S-Adenosyl-L-Methionine Cycle?,"The S-adenosyl-L-methionine cycle starts with S-adenosyl-L-methionine reacting with (a demethylated methyl donor ) dimethylglycine resulting in the release of a hydrogen ion, a betain (a methylated methyl donor) and a S-adenosyl-L-homocysteine. The s-adenosyl-L-homocysteine reacts with a water molecule through a S-adenosylhomocysteine nucleosidase resulting in the release of a adenine and a ribosyl-L-homocysteine. This compound in turn reacts with a s-ribosylhomocysteine lyase resulting in the release of a l-homocysteine and a autoinducer 2. The L-homocysteine reacts with a   N5-methyl-tetrahydropteroyl tri-L-glutamate through a methionine synthase resulting in the release of a tetrahydropteroyl tri-L-glutamate and a methione. The methionine in turn reacts with a water molecule and ATP molecule through a methionine adenosyltransferase resulting in the release of a diphosphate, a phosphate  and a s-adenosyl-L-methionine."
What is the definition of NAD Phosphorylation and Dephosphorylation?,"NAD kinase is required for converting NAD to NADP in various organisms such as groups of archaea, eubacteria and eukaryotes. For example, NAD kinase has shown its important role for the growth in Salmonella enterica and the importance in E.coli. NADP can be converted back to NAD via facilitation of alkaline phosphatase with water (hydroxylation)."
What is the definition of Thioredoxin Pathway?,"In this pathway diagram, clicking on the protein class named ""a reduced thioredoxin"" will display a page showing two instances of this class named reduced thioredoxin 2 and thioredoxin 1. As shown in the gene-reaction schematic on this page, these proteins are the products of genes trxC and trxA, respectively. Clicking on either of the instance names (or on their gene or protein symbols in the gene-reaction schematic) will display a page showing some structural and functional properties of the respective protein.Again in the pathway diagram, clicking on the protein class named ""an oxidized thioredoxin"" will display a page showing two instances of this class named oxidized thioredoxin and oxidized thioredoxin 2. Note that in the gene-reaction schematic shown on this page the reduced thioredoxins are considered to be the direct gene products and their oxidized forms are shown separately as modified forms of the gene products.In E. coli TrxA is a more well studied thiol-disulfide oxidoreductase than TrxC (Trx2). TrxC was identified later as a novel thioredoxin that forms a subfamily of the TrxA protein family. The gene encoding TrxC is under control of the transcriptional regulator OxyR which responds to oxidative stress, although the biological role of TrxC remains to be fully elucidated. (EcoCyc)"
What is the definition of Pyruvate Decarboxylation to Acetyl-CoA?,"The multi-enzyme complex catalyze three reactions that constitute a cycle, which is an essential source of acetyl-CoA. Pyruvate dehydrogenase E1 and dihydrolipoyllysine-residue acetyltransferase catalyzes pyruvic acid to acetyl-CoA and CO2. Acetyl-CoA is required for the TCA cycle. Lipoamide dehydrogenase reduces NAD+ to NADH. "
What is the definition of Methylglyoxal Degradation II?,"The most common pathway for methylglyoxal detoxification is the glyoxalase system, which is composed of two enzymes that together convert methylglyoxal to (R)-lactate in the presence of glutathione. However, in E. coli, a single enzyme, glyoxalase III, catalyzes this conversion in a single step without involvement of glutathione. Activity of glyoxalase III increases at the transition to stationary phase and expression is dependent on RpoS, suggesting that this pathway may be important during stationary phase. (EcoCyc)"
What is the definition of Spermidine Biosynthesis and Metabolism ?,"Spermidine metabolism starts with S-adenosyl-L-methionine reacting with a hydrogen ion through a adenosylmethionine decarboxylase resulting in the release of a carbon dioxide and a S-adenosyl 3-(methylthio)propylamine.  The later compound in turn reacts with putrescine  resulting in the release of a hydrogen ion, a spermidine and a S-methyl-5'-thioadenosine. S-methyl-5'-thioadenosine in turn reacts with a water molecule through a 5-methylthioadenosine nucleosidase resulting in the release of a adenine and a S-methyl-5-thio-D-ribose which in in turn is released into the environment. "
What is the definition of Pyruvate to Cytochrome bd Terminal Oxidase Electron Transfer?,"The reaction of pyruvate to cytochrome bd terminal oxidase electron transfer starts with  2 pyruvate and 2 water molecules reacting in a pyruvate oxidase resulting in the release of 4 electrons into the inner membrane, and releasing 2 carbon dioxide molecules , 2 acetate and 4 hydrogen ion into the cytosol.2 ubiquinone,4 hydrogen ion and 4 electron ion react resulting in the release of 2 ubiquinol . The 2 ubiquinol in turn release 4 hydrogen ions into the periplasmic space through a cytochrome bd-I terminal oxidase and releasing 4 electrons through the enzyme. Oxygen and 4 hydrogen ion reacts with the 4 electrons resulting in 2 water molecules."
What is the definition of Trehalose Biosynthesis I?,"Under conditions of elevated osmotic strength, E. coli can regulate the osmotic strength of the cytoplasm by accumulating K+ ions and some organic molecules, commonly called osmoprotectants or compatible solutes. The preferred osmoprotectant of E. coli is glycine betaine. However, its synthesis relies on an external supply of proline, betaines, or choline. When these compounds are not available, a cell can achieve a moderate level of osmotic tolerance by accumulation of glutamate and trehalose.E. coli synthesizes and accumulates trehalose when exposed to osmotic stress and low temperatures. It is synthesized from UDP-glucose and glucose-6-phosphate via trehalose-6-phosphate, by the action of two enzymes, trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase. Expression of both genes encoding the two enzymes, otsA and otsB, is osmotically regulated. Transcription from these genes increases during osmotic stress and cold shock and when the cells enter stationary phase, and requires the stress sigma factor RpoS. Synthesis of trehalose is also stimulated directly by K+ ion-dependent activation of trehalose-6-phosphate synthase enzyme.Under osmotic stress, E. coli overproduces trehalose, some of which is excreted to the periplasmic space. Once there, it is degraded by the periplasmic trehalase. This process was named ""a futile cycle for controlling the cytoplasmic level of trehalose"". (EcoCyc)"
What is the definition of O-Antigen Building Blocks Biosynthesis?,"Lipopolysaccharide (LPS) is a major component of outer membrane which is consisted of lipid A-core (oligosaccharide) on both inner and outer region and O-antigen (known as distal repeating unit with four sugars: N-acetylglucosamine, glucose, rhamnose and galactose). O-antigen is part of three domains of LPS, which is attached to lipid A-core; however, O-antigen and lipid A-core are synthesized separately. In this pathway, synthesis of three of O-antigen sugars is demonstrated. UDP-α-D-galactose is converted to UDP-D-Galacto-1,4-furanose by facilitation of UDP-galactopyranose mutase. dTTP glucose-1-phosphate is derivatized to dTDP-rhamnose. Fructose-6-phosphate gains an amino group, incorporates an acetate moiety and then acquires a nucleoside diphosphate resulting in UDP-N-acetyl-D-glucosamine."
What is the definition of Acetate Metabolism?,"The acetate biosynthesis starts with acetyl-CoA reacting with phosphate through a phosphate acetyltransferase resulting in the release of a coenzyme A and an acetyl phosphate. The latter compound in turn reacts with ADP through an acetate kinase resulting in the release of an ATP and an acetate. The acetate reacts with ATP and coenzyme A through an acetyl-CoA synthase resulting in the release of a diphosphate, an AMP and an acetyl-CoA. Acetyl-CoA can be biosynthesized by acetoacetate reacting with an acetyl-CoA through an acetoacetyl-CoA transferase resulting in the release of an acetate and an acetoacetyl-CoA.  The acetoacetyl-CoA reacts with an acetyl-CoA acetyltransferase resulting in the release of an coenzyme A and 2 acetyl-CoA"
What is the definition of Adenosine Nucleotides Degradation ?,"The degradation of of adenosine nucleotides starts with AMP reacting with water through a nucleoside monophosphate phosphatase results in the release of phosphate and a adenosine. Adenosine reacts with water and hydrogen ion through an adenosine deaminase resulting in the release of ammonium and a inosine. Inosine reacts with phosphate through a inosine phosphorylase resulting in the release of an alpha-D-ribose-1-phosphate and an hypoxanthine. Hypoxanthine reacts with a water molecule and a NAD molecule through an hypoxanthine hydroxylase resulting in the release of an hydrogen ion, an NADH and a xanthine. Xanthine in turn is degraded by reacting with a water molecule and a NAD through xanthine NAD oxidoreductase resulting in the release of NADH, a hydrogen ion and urate."
What is the definition of Nitrate Reduction VIII?,"NADH dehydrogenase and nitrate reductase can form the anaerobic respiratory chain that can be used for transferring electrons from NADH to nitrate with proton-motive force across cytoplasmic membrane. In E. coli K-12, NDH-I and NDH-II is the two energy conserving NADH dehydrogenases that do not contribute to proton gradient; but both of the enzymes are involved in anaerobic nitrate respiration. NDH-I might be acted as proton pump for translocating 4H+ per NADH oxidised (2e-). In E. coli K-12, there are also two energy conserving (H+/e- = 1) nitrate reductases (nitrate reductase A (NRA) and nitrate reductase Z (NRZ)). Nitrate reductase A can express under the condition of high levels of nitrate in environment; while the expression of nitrate reductase Z doesn't depend on nitrate levels or anaerobiosis. Nitrate and hydrogen atom will be catalyzed to form nitrite and water during nitrate reduction. "
What is the definition of Ethylene Glycol Degradation?,"Ethylene glycol, or 1,2-ethanediol, is used to produce substances such as plastics, solvents, surfactants, explosives and cosmetics. Many of these are discarded into waste treatment and landfills. Both aerobic and anaerobic microorganisms can degrade ethylene glycol. While ethylene glycol cannot be used as a carbon source by wild-type E.coli, it can be utilized by isolated mutant strains. These strains contain two regulatory mutations: a mutation that increases propanediol oxidoreductase levels which functions to metabolize propanediol, and increased activity of Glycolaldehyde dehydrogenase to produce glycolate from glycolaldehyde.  "
What is the definition of Ethanolamine Metabolism?,"Ethanolamine, in E. coli, is produced through phospholipid biosynthesis. Once in the cytosol it can be used to produce acetaldehyde by reacting with ethanolamine ammonia-lyase resulting in the release of ammonium and acetaldehyde."
What is the definition of ADP-L-glycero-beta-D-manno-heptose Biosynthesis?,"ADP-L-glycero-β-D-manno-heptose is a precursor for the inner core lipopolysaccharide (LPS), which is the outer membrane of Gram-negative bacteria. LPS is consisted of lipid A, a core oligosaccharide, and an O-specific polysaccharide (O antigen). This biosynthesis pathway starts with catalyzation of D-sedoheptulose 7-phosphate that produced from pentose phosphate pathway to form D-glycero-D-manno-heptose 7-phosphate by lysophospholipid acyltransferase. D-glycero-D-manno-heptose 7-phosphate later undergoes catalyze to form D-glycero-β-D-manno-heptose 1,7-bisphosphate by fused heptose 7-phosphate kinase (also known as heptose 1-phosphate adenyltransferase) that powered by ATP. D-glycero-β-D-manno-heptose 1,7-bisphosphate will go through hydrolysis by D,D-heptose 1,7-bisphosphate phosphatase to form D-glycero-β-D-manno-heptose 1-phosphate and a phosphate. D-glycero-β-D-manno-heptose 1-phosphate will form ADP-D-Glycero-D-manno-heptose and diphosphate, and eventually ADP-D-Glycero-D-manno-heptose will be biotransformed to ADP-L-glycero-β-D-manno-heptose as the end product of this pathway by ADP-L-glycero-D-mannoheptose-6-epimerase."
What is the definition of 2-O-alpha-Mannosyl-D-glycerate Degradation?,"2-O-α-Mannosyl-D-glycerate (MG; also named as Alpha-Mannosylglycerate) is an organic compound that will affect the osmosis in hyperthermophilic archaea and bacteria. In E.coli, 2-O-α-mannosyl-D-glycerate PTS permease (mngA) import MG into cell, and then phosphorylate MG to 2-O-(6-phospho-α-mannosyl)-D-glycerate by phosphocarrier protein HPr. 2-O-(6-phospho-α-mannosyl)-D-glycerate is converted to glyceric acid as well as mannose 6-phosphate by alpha-mannosidase mngB. Finally, glyceric acid is catalyzed to 2-Phospho-D-glyceric acid with ATP as energy source by Glycerate kinase 2.  E.coli can't use MG as osmotic stress protection, but it can use MG as a carbon source."
What is the definition of Trehalose Degradation I (Low Osmolarity)?,"In E.coli, trehalose can be only synthesized with high osmolarity, and if the osmolarity is low, then the source of trehalose can be only obtained from external via transportation with trehalose PTS permease. However, sugar can be degraded with both low or high osmolarity in E.coli. Glucokinase can phosphorylate free gluocose into glucose-6-phosphate and both glucose-6-phosphate moieties enter glycolysis."
What is the definition of Sedoheptulose Bisphosphate Bypass?,"Sedoheptulose bisphospate bypass pathway demonstrates a series of reaction that form D-Erythrose 4-phosphate for pentose phosphate pathway and glycerone phosphate for glycolysis and pyruvate dehydrogenase pathway. D-Sedoheptulose 7-phosphate is obtained from pentose phosphate pathway, which later converted to sedoheptulose 1,7-bisphosphate via 6-phosphofructokinase-1. Fructose-bisphosphate aldolase class 2 catalyzes sedoheptulose 1,7-bisphosphate to form D-Erythrose 4-phosphate and pyruvate dehydrogenase. "
What is the definition of Cyanate Degradation?,The cyanate degradation pathway begins with the transportation of cyanate into the cytosol through a cynX transporter. Once inside the cytosol  cyanate reacts with hydrogen carbonate and a hydrogen ion through a cyanase resulting in the release of  carbon dioxide and carbamate. Carbamate reacts spontaneously with hydrogen resulting in the release of ammonium and carbon dioxide. Carbon dioxide reacts with water through carbonic anhydrase resulting in the release of hydrogen ion and hydrogen carbonate.
What is the definition of L-Lyxose Degradation?,"L-lyxose is a sugar and a monosaccharide containing five carbon atoms and aldehyde group. Wild-type E.coli can't utilize L-lyxose as its source of carbon and energy. In mutated E.coli, it can metabolize l-lyxose through utilization of enzymes of the rhamnose, arabinose and 2,3-diketo-L-gulonate systems. β-L-lyxopyranose enter cell by L-rhamnose-proton symporter, then convert to l-xylulose by L-rhamnose isomerase. L-xylulose is further metabolized to L-xylulose-5-phosphate with energy ATP. Putative L-ribulose-5-phosphate 3-epimerase can convert L-xylulose -5-phosphate to L-ribulose 5-phosphate, and L-ribulose 5-phosphate 4-epimerase can catalyze L-ribulose 5-phosphate to xylulose 5-phosphate for further pentose phosphate."
What is the definition of D-Serine Degradation?,"The degradation of D-serine begins with the transport of D-serine into the cytosol through a cycA. Once in the cytosol D-serine reacts with ammonia-lyase resulting in the release of a hydrogen ion, water and a 2-aminoprop-2-enoate. This compound in turn reacts spontaneously to produces 2-iminipropanoate. This compound in turn reacts with water and hydrogen ion spontaneously resulting in the release of ammonium and apyruvate."
What is the definition of Ribose Degradation?,"Escherichia coli can utilize the monosaccharide D-ribose as the sole source of carbon and energy for the cell. A high-affinity ABC transport system transports D-ribose into the cell as unphosphorylated beta-D-ribopyranose. Ribose pyranase converts between the furanose and pyranose forms of beta-D-ribose. D-ribofuranose converts between the alpha and beta anomers quickly and spontaneously. Ribokinase converts D-ribose to the pentose phosphate pathway intermediate, D-ribose 5-phosphate, which can enter the central metabolism pathways to meet the cells needs. "
What is the definition of L-Arabinose Degradation I?,"L-arabinose enters E. coli unphosphorylated via a low-affinity proton-driven transporter (AraE) or a high-affinity ATP-driven system (AraFGH). Following entry, it is converted to L-ribulose-5-phosphate by an isomerase and kinase. L-ribulose-5-phosphate is then converted by an epimerase to the pentose phosphate pathway intermediate, D-xylulose-5-phosphate. D-xylulose-5-phosphate then enters metabolism pathways to become precursor metabolites, reducing power and metabolic energy. "
What is the definition of Xylose Degradation I?,"Escherichia coli can utilize D-xylose as the sole source of carbon and energy for the cell. A low-affinity proton motive force or a high-affinity ATP-driven (ABC) transport system brings unphosphorylated D-xylose into the cell. Following entry, D-xylose is converted to D-xylulose by an isomerase and then converted to the pentose phosphate pathway intermediate, D-xylulose 5-phosphate via a kinase. D-xylulose 5-phosphate can then enter pathways of metabolism to meet the cells needs. "
What is the definition of L-Threonine Degradation to Methylglyoxal?,"L-threonine is degrade into methylglyoxal (pyruvaldehyde) by first reacting with a NDA dependent threonine dehydrogenase resulting in the release of a hydrogen ion, an NADH and a 2-amino-3-oxobutanoate. The latter compound reacts spontaneously with a hydrogen ion resulting in the release of a carbon dioxide and a aminoacetone. The aminoacetone in turn reacts with an oxygen and a water molecule through an aminoacetone oxidase resulting in the release of a hydrogen peroxide, ammonium and a methylglyoxal which can then be incorporated in the methylglyoxal degradation pathways."
What is the definition of Lipoate Biosynthesis and Incorporation I?,"Lipoate is an essential cofactor for key enzymes of oxidative metabolism. Mechanism of lipoate biosynthesis is similar to biotin biosynthesis. Octanoyltransferase facilitates the tranfer of octanoate moiety from octanoate-ACP to particular lysyl residues in lipoate-dependent enzymes. This process regenerates the acyl-carrier in the process, and create an octanylated domains in lipoate-dependent enzymes. Lipoyl synthase combines with S-adenosyl-L-methionine to generate an active lipoylated domain by converting the octanoyl side chain to an active lipoyl. Lipoyl synthase also split S-Adenosyl methionine (AdoMet) into 5'-deoxyadenosyl radical (later becomes 5'-deoxyadenosine by abstracting a hydrogen from a C-H bond) and L-methionine. L-methionine will undergo S-Adenosyl-L-Methionine Biosynthesis."
What is the definition of 2-Oxoglutarate Decarboxylation to Succinyl-CoA?,"2-oxoglutarate dehydrogenase complex is consisted of oxoglutarate decarboxylase, dihydrolipoyl succinyltransferase and dihydrolipoyl dehydrogenase), which is a rate-limiting enzyme of the citric acid cycle (TCA cycle) in prokaryote. The reaction that catalyzed by 2-oxoglutarate dehydrogenase complex can be generalized as 2-oxoglutarate + coenzyme A + NAD+ → succinyl-CoA + CO2 + NADH. During the OGDHC reaction cycle, 2-oxoglutarate is bound and decarboxylated by E1(o), a thiamin-diphosphate cofactor containing enzyme. The succinyl group is transferred to the lipoyl domain of E2(o) where it is carried to the active site and transferred to coenzyme A, forming succinyl-CoA. During this transfer the lipoyl group is reduced to dihydrolipoyl. The succinyl-CoA is released and the lipoyl domain of E2(o) is oxidized by E3 via transfer of protons to NAD, forming NADH and regenerating the lipoyl group back to lipoyllysine for another cycle. Under aerobic growth conditions the OGDHC not only catalyzes a key reaction in the TCA cycle, it also provides succinyl-CoA for methionine and lysine biosynthesis, the latter pathway also leading to peptidoglycan biosynthesis. The synthesis of the OGDHC is repressed by anaerobiosis and is also subject to glucose repression. It is induced by aerobic growth on acetate. (EcoCyc)"
What is the definition of Cyclopropane Fatty Acid (CFA) Biosynthesis?,"Cyclopropane fatty acids (CFA) are synthesized by the modification of an unsaturated bond of acyl chains of phospholipid bilayers by methylenation via cyclopropane fatty acyl phospholipid synthase. CFA phospholipid synthase is a unique enzyme in that it acts on the nonpolar part of the phospholipids. The bond that is modified is about nine to eleven carbon atoms from the glycerol backbone. S-adenosyl-L-methionine donates a methylene group to the cis double bond of the unsaturated fatty acid. CFA synthase acts on phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Cyclopropane fatty acids in the cytoplasmic membrane protect cells from ethanol, high osmotic pressure and other environmental stressors. "
What is the definition of L-Cysteine Degradation?,"The degradation of cysteine starts with L-cysteine reacting with l-cysteine desulfhydrase resulting in the release of a hydrogen sulfide, a hydrogen ion and a a 2-aminoprop-2-enoate. The latter compound in turn reacts spontaneously to form a 2-iminopropanoate. This compound in turn reacts spontaneously with water and a hydrogen ion resulting in the release of ammonium and pyruvate."
What is the definition of BaeSR Two-Component Signal Transduction System?,"In E.coli K-12, two component systems (TCSs) are responsible for sensing and response to changes in environmental conditions. Sensor kinase response environmental signals by auto-phosphorylate on membrane, which transfer a phosphoryl group to a response regulator (RR) for activation. Signal transduction histidine-protein kinase (BaeS) is sensor kinase and transcriptional regulatory protein (BaeR) is the response regulator in the TCSs. BaeR overexpression may lead to greater resistance to novobiocin and deoxycholate. "
What is the definition of Methylglyoxal Degradation I?,"The degradation of methylglyoxal starts with methylglyoxal being degraded by interacting with glutathione and a glyoxalase resulting in the release of a (R)-S-lactoylglutatione. This compound in turn reacts with a water molecule through a glyoxalase II resulting in the releas of glutathione, a hydrogen ion and an R-lactate. The R-lactate in turn reacts with an ubiquinone through a D-lactate dehydrogenase resulting in the release of an ubiquinol and a pyruvate which can then be incorporated the pyruvate metabolism"
What is the definition of Operon: Cytosine Transport?,"The cytosine transport operon genes constitutes a bicistronic operon with a unique promoter, regulated by hypoxanthine and guanine which repress the synthesis of both cytosine deaminase and cytosine transport protein. "
What is the definition of Operon: Clp Protease?,The ClpPX protease is a bicistronic operon involved in the degradation of of particular substrates distinct to those degrade by ClpAP. The operon also includes a Rho-independent terminator for regulation of the operon.
What is the definition of Operon: Biotin Biosynthesis?,"The biotin operon is a polycistronic operon regulated by accB and accC. The operon repressed by the BirA protein,  a transcriptional factor but also a biotin protein ligase that targets the AccB protein. Therefore, when AccB is overproduced, the bio operon is derepressed, since BirA is linked to AccB. On the other hand, as AccC protein  is overproduced, AccB is removed from the BirA-AccB complex, thus BirA is allowed to freely bind to its operator site to repress the bio operon."
What is the definition of Operon: Cytochrome bd Terminal Oxidase appCBA?,"The cytochrome bd terminal oxidase is a polycystronic operon comprised of appC, appB and appA. This operon is expressed in response to oxygen deprivation and it is possitively controlled by the product of appR (rpoS). This operon can also be positively controlled by appY and negatively controlled by  cAMP and its receptor protein CAP."
What is the definition of Operon: Cell Division Control?,"The cell division control operon dicB is a polycistronic operon consisting of ydfA, ydfB, ydfC, dicB, ydfD, and ydfE which is negatively regulated by dicA gene product. DicB is a Qin prophage cell division inhibition protein."
What is the definition of Operon: Mannose Uptake?,"The mannose operon is a polycistronic operon consisting of manX,manY, and manZ. At high concentrations of CAP, a CRP-cAMP DNA-binding transcriptional dual regulator binds either to a weak CAP site upstream from manX in the region -180 to -100, or to a class II promoter where CAP and NagC bind simultaneously allowing for the activation of transcription.There are two binding sites for the NagC repressor upstream from manX, one at -79 position and one at the -13 position.  Other methods of repression of transcription of the manXYZ operon include the binding of a unmodified Cra DNA-binding transcriptional dual regulator, or a Mlc  DNA-binding transcriptional repressor which binds to NagC and the CAP site. "
What is the definition of Operon: Mannose Uptake II?,"The mannose operon is a polycistronic operon consisting of manX,manY, and manZ. At high concentrations of CAP, a CRP-cAMP DNA-binding transcriptional dual regulator binds either to a weak CAP site upstream from manX in the region -180 to -100, or to a class II promoter where CAP and NagC bind simultaneously allowing for the activation of transcription. There are two binding sites for the NagC repressor upstream from manX, one at -79 position and one at the -13 position. Other methods of repression of transcription of the manXYZ operon include the binding of a unmodified Cra DNA-binding transcriptional dual regulator, or a Mlc DNA-binding transcriptional repressor which binds to NagC and the CAP site."
What is the definition of Operon: Mannose Uptake Inactivation?,"The mannose operon is a polycistronic operon consisting of manX,manY, and manZ. At high concentrations of CAP, a CRP-cAMP DNA-binding transcriptional dual regulator binds either to a weak CAP site upstream from manX in the region -180 to -100, or to a class II promoter where CAP and NagC bind simultaneously allowing for the activation of transcription.There are two binding sites for the NagC repressor upstream from manX, one at -79 position and one at the -13 position.  Other methods of repression of transcription of the manXYZ operon include the binding of a unmodified Cra DNA-binding transcriptional dual regulator, or a Mlc  DNA-binding transcriptional repressor which binds to NagC and the CAP site."
What is the definition of Operon: Periplasmic Binding Protein Inner Membrane Protein Controlled by araC?,"The periplasmic binding protein inner membrane protein operon is a polycystronic operon consisting of araF, araG, and araH. This operon's transcription is controlled either by a CRP-cAMP DNA-binding transcriptional dual regulator binding to a a site 42 bp upstream of the transcription start site, or  by a bound AraC which binds either to 70, 91, 145 or 166 bp upstream of the transcription start site"
What is the definition of Operon: De Novo Purine Nucleotide Biosynthesis?,"The de novo purine nucleotide biosynthesis operon consists of the following genes: cvpA, purF and ubiX followed by a Rho-Independent terminator. This operon is regulated by a PurR-hypoxanthine DNA-binding transcriptional repressor which represses the transcription of the  operon."
What is the definition of Operon: Folylpolyglutamate Synthase?,"The folylpolyglutamate synthase operon consist of folC and dedD and a terminator. The product of folC is folylpolyglutamate synthase (also known as Dihydrofolate synthase), which is used for balancing the concentration of folylpolyglutamate, folate homeostasis and proliferating cells' survival. The product of dedD is cell division protein DedD, which is required for efficient cell constriction."
What is the definition of Asparagine Metabolism?,"In both eukaryotes and prokaryotes, L-asparagine is biosynthesized from L-aspartate by amidation using L-glutamine as an amino group donor which both of reactions are driven by ATP. In the first reaction, asparagine synthetase [glutamine-hydrolyzing] 1 catalyzes L-aspartic acid to form L-Asparagine. In the second reactions, asparagine synthetase [glutamine-hydrolyzing] 1 and 2 both catalyze L-aspartic acid to form L-Asparagine. Asparagine gets metabolized back into L-aspartic acid by reacting with water through a L-asparaginase 1 resulting in the release of ammonium and L-aspartic acid. The only known role of L-asparagine is incorporation into proteins."
What is the definition of Operon: Sugar Uptake?,"The sugar uptake operon is a polycistronic operon consisting of ptsH, ptsI, and crr. The expression of these genes are controlled by CRP-cAMP DNA-binding transcriptional dual regulator binding at -60.5, -42.5, -63.5, or -48.5 bp in order to activate transcription. As for the repression of the operon, NagC (NagC DNA-binding transcriptional dual regulator)  binds  to 7, -35.5, 13 or 16 to repress the operon. Other methods of repression include Mlc (Mlc DNA-binding transcriptional repressor) binding to 13 bp site and Cra (Cra DNA-binding transcriptional dual regulator) binding to -55.5"
What is the definition of Operon: Pyridoxal 5'-Phosphate Biosynthesis?,"The pyridoxal 5'-phosphate biosynthesis operon is a bicistronic operon consisting of pdxJ and acpS and it is regulated by the PDX box. The product of pdxJ is pyridoxine 5'-phosphate synthase, which is required for forming pyridoxal 5'-phosphate (also known as active form of vitamin B6). The product of acpS is holo-[acyl-carrier-protein] synthase, which is required for transferring 4'-phosphopantetheine moiety to 'Ser-36' of acyl-carrier-protein from coenzyme A."
What is the definition of Operon: Biosynthesis of Aromatic Amino Acids?,"The biosynthesis of aromatic amino acids operon is a bicistronic operon consisting of aroF and tyrA. This operon is regulated by a tyrR-tyrosine DNA-binding transcriptional repressor which represses transcirption of the operon. The tyrR-tyrosine binds to either-29.5, -52.5, or -104.5 bp"
What is the definition of Operon: Glycine Cleavage System?,"The glycine cleavage system is a polycistronic operon consisting of gcvT, gcvH, and gcvP. This operon irs regulated positively by  CRP-cAMP DNA-binding transcriptional dual regulator binding to -145.5 or -313.15,  Lrp (Lrp transcriptional dual regulator) binding to -161 or  GcvA (GcvA DNA-binding transcriptional dual regulator)  binding to -226 or -258It regulates negatively through  GcvA (GcvA DNA-binding transcriptional dual regulator)  binding to -44, -66, -226 or -258, or  PurR-Hypoxanthine DNA-binding transcriptional repressor binding to 7.5"
What is the definition of Operon: Glycine Cleavage System II?,"The glycine cleavage system is a polycistronic operon consisting of gcvT, gcvH, and gcvP. This operon irs regulated positively by CRP-cAMP DNA-binding transcriptional dual regulator binding to -145.5 or -313.15, Lrp (Lrp transcriptional dual regulator) binding to -161 or GcvA (GcvA DNA-binding transcriptional dual regulator) binding to -226 or -258 It regulates negatively through GcvA (GcvA DNA-binding transcriptional dual regulator) binding to -44, -66, -226 or -258, or PurR-Hypoxanthine DNA-binding transcriptional repressor binding to 7.5"
What is the definition of Operon: Ribosomal Protein Inactivation?,"The ribosomal protein operon is a polycistronic operon consisting of the genes: rpsU, dnaG, and rpoD. This operon is repressed by the LexA binding to the 4.5 bp site, or by an alarmone-based regulation, DksA-ppGpp, which inhibit transcription initiation."
What is the definition of Operon: Ribosomal Protein rpsO?,"The ribosomal protein operon is a bicistronic operon consisting of rpsO and pnp. This operon is regulated by a Rho independent terminator, allowing for only rpsO to be transcribed if the terminator is formed"
What is the definition of Operon: Arsenical Resistance?,"The arsenical resistance operon consists of arsR, arsB and arsC. This operon is regulated by ArsR DNA-binding transcriptional repressor binding to the -41.5 bp site. Without the transcriptional repressor, RNA polymerase sigma 70 complex will bind to promoter of ars operon to enable the facilitation of transcription of gene arsA, arsR and arsC. The products of these gene are required for detoxification of arsenite, arsenate and antimonite. Gene arsB and arsA will encode the arsenical pump membrane protein, which is essential to form channel of arsenite pump to pump arsenite and antimonite out of cell. Gene arsC will encode arsenate reductase, which will reduce arsenate to arsenite. "
What is the definition of Operon: Arsenical Resistance Inactivation?,"The arsenical resistance operon consists of arsR, arsB and arsC. This operon is regulated by ArsR DNA-binding transcriptional repressor binding to the -41.5 bp site. With the transcriptional repressor bind to ArsR DNA-binding site of ars operon, there is no facilitation of transcription of gene arsR, arsB and arsC."
What is the definition of Operon: Xylose Transport?,"The xylose transport operon is a polycistronic operon consisting of xylfF, xylG, xylH and xylR. This operon is regulated by CRP-cAMP DNA-binding transcriptional dual regulator binding to a -180.5 site to activate transcription.Other methods of activating transcription include the xylR-xylose DNA binding transcriptional activator binding either to -61.5 or -40.5.The methods of repression of the operon are regulated by Fis DNA-binding transcriptional dual regulator which binds either to -82, -75 or 22"
What is the definition of Operon: Xylose Transport II?,"The xylose transport operon is a polycistronic operon consisting of xylfF, xylG, xylH and xylR. This operon is regulated by CRP-cAMP DNA-binding transcriptional dual regulator binding to a -180.5 site to activate transcription. Other methods of activating transcription include the xylR-xylose DNA binding transcriptional activator binding either to -61.5 or -40.5. The methods of repression of the operon are regulated by Fis DNA-binding transcriptional dual regulator which binds either to -82, -75 or 22"
What is the definition of Operon: Mannitol Uptake?,"The mannitol uptake operon is a bicistronic operon consisting of the genes mtlA and mtlD. The transcription of this operon is activated by the binding of  CRP-cAMP DNA-binding transcriptional dual regulator to either : -261.5, -219.5, -175.5, -102.5 or -58.5. The transcription of this operon is repressed by either the binding of  Cra (Cra DNA-binding transcriptional dual regulator) to -22.5 or the binding of Fis DNA-binding transcriptional dual regulator to the 137 bp site."
What is the definition of Operon: Mannitol Uptake Inactivation?,"The mannitol uptake operon is a bicistronic operon consisting of the genes mtlA and mtlD. The transcription of this operon is activated by the binding of CRP-cAMP DNA-binding transcriptional dual regulator to either : -261.5, -219.5, -175.5, -102.5 or -58.5. The transcription of this operon is repressed by either the binding of Cra (Cra DNA-binding transcriptional dual regulator) to -22.5 or the binding of Fis DNA-binding transcriptional dual regulator to the 137 bp site."
What is the definition of Operon: Ribonuclease & Pyrimidine Biosynthesis?,The  ribonuclease & pyrimidine biosynthesis operon is a bicistronic operon consisting of the genes rph and pyrE. This operon is regulated by a rho-independent terminator in between rph and pyrE and a rho-independent terminator downstream of pyrE. 
What is the definition of Operon: DNA/RNA Processing?,"The DNA/RNA processing operon is a polycistronic operon consisting of the genes: rpoZ, spoT, trmH, and recG. This operon is regulated allostericly by DksA-ppGpp which represses transcription. RpoZ encodes the omega subunit of the Escherichia coli RNA polymerase, spoT encodes guanosine-3‘,5‘-bispyrophosphate (ppGpp), trmH catalyzes the 2'-O methylation of guanosine at position 18 in tRNA, and recG encodes a DNA helicase."
What is the definition of Operon: Replication (DnaA)?,"The DnaA replication operon consists of the genes dnaA, dnaN and recF. This operon can be regulated by two promoters, one at -232 and the other at -153. The promoter at -232 is activated by an ArgP DNA-binding transcriptional activator binding to either 219.5, -49.5 or -69.5 and it can be repressed by a  DnaA-ATP transcriptional dual regulator binding to 23 bp downstream the promoter. The second promoter is activated and repressed by DnaA binding to -40, -51, or -61 , and repressed by DnaA binding to -57 "
What is the definition of Operon: Replication (DnaA) II?,"The DnaA replication operon consists of the genes dnaA, dnaN and recF. This operon can be regulated by two promoters, one at -232 and the other at -153. The promoter at -232 is activated by an ArgP DNA-binding transcriptional activator binding to either 219.5, -49.5 or -69.5 and it can be repressed by a DnaA-ATP transcriptional dual regulator binding to 23 bp downstream the promoter. The second promoter is activated and repressed by DnaA binding to -40, -51, or -61 , and repressed by DnaA binding to -57"
What is the definition of Operon: Methionine Biosynthesis?,"The methionine biosynthesis operon is a bicistronic operon consisting of metB and metL genes. This operon's transcription is activated by PhoP-Phosphorylated DNA-binding transcriptional dual regulator binding to a -20 bp site from the promoter. It is repressed by a MetJ-S-adenosylmethionine DNA-binding transcriptional repressor binding to either: -30.5, -38.5, -40.5, -46.5,-48.5 or -56.5"
What is the definition of Operon: Maltodextrins and Maltose Transport?,"The maltodextrins and maltose transport operon consist of the genes malE, malF, malG. This operon's transcription is activated by Fis DNA-binding transcriptional dual regulator)binding to either 52 or -116. Transcription can also be activated by MalT-Maltotriose-ATP DNA-binding transcriptional activator  binding to -41.5, -51.5, -197.5, -207.5, or -231.5. Transcription can also be activated by  CRP-cAMP DNA-binding transcriptional dual regulator binding to -76.5, -105.5, -139.5, or -171.5.The repression of transcription of this operon regulated by  CreB-Phosphorylated DNA-binding transcriptional regulator binding to 18.5"
What is the definition of Operon: Maltodextrins and Maltose Transport II?,"The maltodextrins and maltose transport operon consist of the genes malE, malF, malG. This operon's transcription is activated by Fis DNA-binding transcriptional dual regulator)binding to either 52 or -116. Transcription can also be activated by MalT-Maltotriose-ATP DNA-binding transcriptional activator binding to -41.5, -51.5, -197.5, -207.5, or -231.5. Transcription can also be activated by CRP-cAMP DNA-binding transcriptional dual regulator binding to -76.5, -105.5, -139.5, or -171.5. The repression of transcription of this operon regulated by CreB-Phosphorylated DNA-binding transcriptional regulator binding to 18.5"
What is the definition of Operon: Malto Dextrins Uptake?,"The malto dextrin uptake operon involves the genes malK, lamB, and malM. The operon's transcription can be activated by having MalT-Maltotriose-ATP DNA-binding transcriptional activator bind to -230.5, -220.5, -74.5, -64.5 or -40.5 bp from the promoter. The operon's transcription can also be activated by CRP-cAMP DNA-binding transcriptional dual regulator binding  to -195.5, -166.5, -132.5, or -100.5 bp from the promoter."
What is the definition of Operon: Malto Dextrins Uptake II?,"The malto dextrin uptake operon involves the genes malK, lamB, and malM. The operon's transcription can be activated by having MalT-Maltotriose-ATP DNA-binding transcriptional activator bind to -230.5, -220.5, -74.5, -64.5 or -40.5 bp from the promoter. The operon's transcription can also be activated by CRP-cAMP DNA-binding transcriptional dual regulator binding to -195.5, -166.5, -132.5, or -100.5 bp from the promoter."
What is the definition of Operon: Phosphonate Utilization?,"The phosphonate utilization operon is a polycistronic operon consist of the genes: phnC, phnD, phnE, phnF, phnG, phnH, phnI, phnJ, phnK, phnL, phnM, phnN,phnO and phnQ.  This operon's transcription is activated by a PhoB-Phosphorylated DNA-binding transcriptional dual regulator  binding on an unspecified binding site."
What is the definition of Operon: Lysine Decarboxylase?,"The lysine carboxylase operon consists of cadB and cadA genes. This operon's transcription activation can be controlled by GadE-RcsB DNA binding transcriptional activator, GadX (GadX DNA-binding transcriptional dual regulator) , CadC (CadC DNA-binding transcriptional activator)  or Lrp (Lrp transcriptional dual regulator)  in unspecified binding site locations.This operon's transcription inactivation is controlled by  H-NS (H-NS DNA-binding transcriptional dual regulator)  binding to -32, -129, -175, -260 or -317 bp of the promoter site.This operon's transcription inactivation can also be controlled by  ArcA-Phosphorylated DNA-binding transcriptional dual regulator  binding to -179 bp of the promoter site."
What is the definition of Operon: Lysine Decarboxylase II?,"The lysine carboxylase operon consists of cadB and cadA genes. This operon's transcription activation can be controlled by GadE-RcsB DNA binding transcriptional activator, GadX (GadX DNA-binding transcriptional dual regulator) , CadC (CadC DNA-binding transcriptional activator) or Lrp (Lrp transcriptional dual regulator) in unspecified binding site locations. This operon's transcription inactivation is controlled by H-NS (H-NS DNA-binding transcriptional dual regulator) binding to -32, -129, -175, -260 or -317 bp of the promoter site. This operon's transcription inactivation can also be controlled by ArcA-Phosphorylated DNA-binding transcriptional dual regulator binding to -179 bp of the promoter site."
What is the definition of Operon: High Frequency of Lysogenization?,"The high frequency of lyzogenization operon is a polycistronic operon consisting of the genes: hfq, hflX, hflK and hflC. This operon is regulated by CRP-cAMP DNA-binding transcriptional dual regulator being binded to a crp binding site in the -96.5 bp from the promoter"
What is the definition of Operon: Pyrimidine Biosynthesis ?,"The pyrimidine biosynthesis operon consists of the genes pyrB and pyrI. This is a bicistronic operon. The operon transcription is negatively regulated by the intracellullar levels of UTP. The higher the UTP levels, the less expressiong of the operon"
What is the definition of Operon: Glucuronate Pathway?,The glucuronate pathway operon is a bicistronic operon consisting of the genes uxuA and uxuB. The transcription of this operon is activated by  CRP-cAMP DNA-binding transcriptional dual regulator binding to -57.5 or -142.5 bp off the promoter. The transcription of the operon can be repressed by multiple means:-UxuR (UxuR DNA-binding transcriptional repressor) binding -159.5 or -53.5 off the promoter-ExuR (ExuR DNA-binding transcriptional repressor) binding to -159.5 or -53.5 off the promoter-OxyR (OxyR DNA-binding transcriptional dual regulator) binding to -54 or -32 off the promoter
What is the definition of Operon: Glucuronate Pathway Inactivation?,The glucuronate pathway operon is a bicistronic operon consisting of the genes uxuA and uxuB. The transcription of this operon is activated by CRP-cAMP DNA-binding transcriptional dual regulator binding to -57.5 or -142.5 bp off the promoter. The transcription of the operon can be repressed by multiple means: -UxuR (UxuR DNA-binding transcriptional repressor) binding -159.5 or -53.5 off the promoter -ExuR (ExuR DNA-binding transcriptional repressor) binding to -159.5 or -53.5 off the promoter -OxyR (OxyR DNA-binding transcriptional dual regulator) binding to -54 or -32 off the promoter
What is the definition of Operon: Nucleotide and Deoxyribonucleotide Catabolism?,"The nucleotide and deoxyribonucleotide operon is a polycistronic operon consisting of the genes DeoC, DeoA, DeoB and DeoD. This operon's transcription is activated by Fis DNA-binding transcriptional dual regulator binding to a -102 bp site off the promoter. This operon can also be activated by having CRP-cAMP DNA-binding transcriptional dual regulator binding either to -93.5 or -40.5. The repression of the operon's transcription can be controlled by multiple sites upsteam the promoter:- DeoR (DeoR DNA-binding transcriptional repressor) -887, -309, -8 for promoter deop2 and   -609, -8, and 269 for promoter deop1- CRP-cAMP DNA-binding transcriptional dual regulator binding at -93.5 for promoter deop2- CytR (CytR DNA-binding transcriptional repressor) -87.5, -70.5, -61 for promoter deop2-ModE-MoO42- DNA-binding transcriptional dual regulator -35 for promoter deop2"
What is the definition of Operon: Nucleotide and Deoxyribonucleotide Catabolism II?,"The nucleotide and deoxyribonucleotide operon is a polycistronic operon consisting of the genes DeoC, DeoA, DeoB and DeoD. This operon's transcription is activated by Fis DNA-binding transcriptional dual regulator binding to a -102 bp site off the promoter. This operon can also be activated by having CRP-cAMP DNA-binding transcriptional dual regulator binding either to -93.5 or -40.5. The repression of the operon's transcription can be controlled by multiple sites upsteam the promoter: - DeoR (DeoR DNA-binding transcriptional repressor) -887, -309, -8 for promoter deop2 and -609, -8, and 269 for promoter deop1 - CRP-cAMP DNA-binding transcriptional dual regulator binding at -93.5 for promoter deop2 - CytR (CytR DNA-binding transcriptional repressor) -87.5, -70.5, -61 for promoter deop2 -ModE-MoO42- DNA-binding transcriptional dual regulator -35 for promoter deop2"
What is the definition of Operon: DNA Replication (dnaTC)?,The DNA replication (dnaTC) operon is a bicistronic operon consisting of dnaC and dnaT. This operon is regulated by a rho-independent terminator. The product of dnaC and dnaT are respectively primosomal protein 1 and DNA replication protein DnaC. DnaT is also responsible for inducting replication of stable DNA during SOS response.
What is the definition of The Oncogenic Action of 2-Hydroxyglutarate?,"The compound 2-hydroxyglutarate is the product of gain-of-function mutations producing mutIDH1 and mutIDH2 in the cytosolic and mitochondrial isoforms of isocitrate dehydrogenase (IDH). This compound is derived from the TCA cycle. The compound 2-hydroxyglutarate is sufficiently similar in structure to 2-oxogluratate (2OG) to inhibit a range of 2OG-dependent dioxygenases,including histone lysine demethylases (KDMs) and the ten-eleven translocation (TET) family of 5-methylcytosine (5mC) hydroxylases. In turn, this leads to modulations of HIF-mediated hypoxia responses and alterations in gene expression through global epigenetic remodelling that may contribute to malignant transformation."
What is the definition of The Oncogenic Action of Succinate?,"Hypoxia-inducible factor In many tumours, oxygen availability becomes limited (hypoxia) very quickly during cancer development. The major regulator of the response to hypoxia is the HIF transcription factor. Under normal oxygen levels, the protein levels of HIF alpa is very low due to constant degradation, mediated by a sequence of post-translational modification events catalyzed by the enzymes PHD1,2 and 3, (also known as EglN2,1 and 3). Under hypoxic conditions, HIF alpha escapes hydroxylation and degration. Succinate dehydrogenase (SDH)  is a collection of housekeeping genes (SDHA,B,C,D), but mutations in those genes allows for succinate to accumulate and cross the mitochondrial barrier through a dicarboxylate carrier.  Once in the cytosol, it inhibits the activity of the PHD1,2 and 3 since succinate is a product of the enzyme, it acts as feedback inhibition."
What is the definition of The Oncogenic Action of Fumarate?,"Hypoxia-inducible factor In many tumours, oxygen availability becomes limited (hypoxia) very quickly during cancer development. The major regulator of the response to hypoxia is the HIF transcription factor. Under normal oxygen levels, the protein levels of HIF alpa is very low due to constant degradation, mediated by a sequence of post-translational modification events catalyzed by the enzymes PHD1,2 and 3, (also known as EglN2,1 and 3). Under hypoxic conditions, HIF alpha escapes hydroxylation and degration. Fumarate hydratase (FH) is a housekeeping gene, but mutations in this gene allows for fumarate to accumulate and cross the mitochondrial barrier through a dicarboxylate carrier. Once in the cytosol, it inhibits the activity of the PHD1,2 and 3 since it is chemically similar to succinate. Having a double bond in the centre of the dicarboxylic acid, fumarate is a rigid molecule compared to succinate making it a probable possibility for fumarate to interacts better with PHDs."
What is the definition of Proline Metabolism ?,"The biosynthesis of L-proline in E. coli involves L-glutamic acid being phosphorylated through an ATP driven glutamate 5-kinase resulting in a L-glutamic acid 5-phosphate. This compound is then reduced through a NADPH driven gamma glutamyl phosphate reductase resulting in the release of a phosphate, a NADP and a L-glutamic gamma-semialdehyde. L-glutamic gamma-semialdehyde is dehydrated spontaneously, resulting in a release of water,hydrogen ion and 1-Pyrroline-5-carboxylic acid. The latter compound is reduced by an NADPH driven pyrroline-5-carboxylate reductase which is subsequently reduced to L-proline. L-proline works as a repressor of the pyrroline-5-carboxylate reductase enzyme and glutamate 5-kinase. In E. coli, the biosynthesis of L-proline from L-glutamate is governed by three genetic loci namely proB, proA and proC. The first reaction in the pathway is catalyzed by γ-glutamyl kinase, encoded by proB . The second reaction, NADPH-dependent reduction of γ-glutamyl phosphate to glutamate-5-semialdehyde, in the pathway is catalyzed by glutamate-5-semialdehyde dehydrogenase, encoded by proA . These two enzymes aggregate into a multimeric bi-functional enzyme complex known as γ-glutamyl kinase-GP-reductase multienzyme complex. It is believed that the complex formation serves to protect the highly labile glutamyl phosphate from the hostile nucleophilic and aqueous environment found in the cell . The final step in the pathway, the reduction of pyrroline 5-carboxylate to L-proline, is catalyzed by an NADPH-dependent pyrroline-5-carboxylate reductase encoded by proC . Proline is metabolized by being converted back to L-glutamate, which is further degraded to α-ketoglutarate, an intermediate of the TCA cycle. The process by which proline is turned into L-glutamate starts with L-proline interacting with ubiquinone through a bifunctional protein putA resulting in an ubiquinol, a hydrogen ion and a 1-pyrroline-5-carboxylic acid. The latter compound is then hydrated spontaneously resulting in a L-glutamic gamma-semialdehyde. This compound is then processed by interacting with water through an NAD driven bifunctional protein putA resulting in a hydrogen ion, NADH and L-glutamic acid."
What is the definition of Glutaminolysis and Cancer?,"The glutaminolysis pathway catabolizes glutamine to generate ATP and lactate. Glutamine not only provides a major substrate for respiration but also for the synthesis of other macromolecules, such as nucleotides, proteins and hexosamines. It also  macromolecule biosynthesis, glutaminolysis also has an important role in regulating redox balance, mTOR signaling, apoptosis and autophagy.High extracellular glutamine concentrations stimulate tumor growth and are essential for cell transformation. The transportation of glutamine in and out regulates mTOR activation to coordinate cell growth and proliferation.Glutaminolysis is a series of biochemical reactions by which glutamine is degraded into glutamate, aspartate, CO2, pyruvate, lactate, alanine and citrate.Glutamine is imported through ASCT2 and SN2, once inside the cell, it can be deaminated into glutamate. Glutamate is converted into Oxoglutaric acid which then is incorporated into the TCA cycle. Once it reaches malic acid, it is transported outside the mitochondria and transformed into pyruvic acid and lactate.The oxoglutaric acid can also be transformed into citric acid which then gets turned into acetyl coa and get incorporated into the lipid synthesis"
What is the definition of L-Alanine Metabolism ?,"L-alanine metabolized from pyruvate and glutamate reacting through a Alanine aminotransferase resulting in the release of a oxoglutaric acid and a alanine. Alanine is degraded by alanine aminotransferase to form pyruvic acid. Meanwhile, oxoglutaric acid is converted to L-glutamic acid also by alanine aminotransferase. Pyruvate is transported into mitochondria for further metabolism."
What is the definition of Aspartate Metabolism ?,"Aspartate (also named as L-aspartic acid) is an α-amino acid that can be used for protein biosynthesis. Oxalacetic acid is produced from aspartic acid by mitochondrial aspartate aminotransferase, then oxalacetic acid is reduced to malic acid by malate dehydrogenase. Malic acid enters mitochondria through mitochondrial dicarboxylate transporter and forms oxalacetic acid by facilitation of malate dehydrogenase. In the final step, oxalacetic acid is catalyzed by mitochondrial aspartate aminotransferase to form aspartate."
What is the definition of Glutamate Metabolism?,The glutamate metabolism in S. cerevisiae happens both inside the mitochondria and the cytosol.The process in the mitochondria starts with asparagine being metabolized into ornithine. Ornithine then reacts with an ornithine aminotransferase resulting in the release of a L-glutamic gamma semialdehyde. This compound then reacts with an aldehyde dehydrogenase resulting in the release of L-glutamic acid. Mitochondrial L-glutamic acid is degraded by reacting with a glutamate dehydrogenase resulting in the release of oxoglutaric acid which is then incorporated into the TCA cycle.The process of glutamate metabolism in the cytosol starts with the synthesis of L-glutamic acid from either L-glutamine or from oxoglutaric acid.1. L-glutamine reacts with Oxoglutaric acid through a NAD dependent glutamate synthase resulting in the release of glutamic acid2. Oxoglutaric acid reacts with ammonium through a NADP dependent glutamate dehydrogenase resulting in the release of water and L-glutamic acid 3.Oxoglutaric acid reacts with ammonium through a NADP dependent glutamate dehydrogenase 2 resulting in the release of water and L-glutamic acid The degradation of L-glutamic acid starts with water through an  glutamate dehydrogenase resulting in the release of Oxoglutaric acid and ammonium. L-glutamic acid can also be degraded by reacting with a glutamate decarboxylase resulting in the release of GABA. GABA is further degraded by 4-aminobutyrate aminotransferase resulting in the release of succinic acid semialdehyde.This compound is then metabolized into succinic acid through a succinate semialdehyde dehydrogenase
What is the definition of TCA Cycle?,"Citric acid cycle (also known as  tricarboxylic acid cycle (TCA) and Krebs cycle) contains series of reactions that involved enzyme catalyzation which are essential for all living cells that require oxygen for cellular respiration. In mitochondria (for eukaryotes), TCA cycle begins with acetyl-CoA and oxaloacetic acid (oxaloacetate) be catalyzed to form citric acid (citrate) by citrate synthase 3. Then, 3-isopropylmalate dehydratase with cofactor 4Fe-4S can catalyze citrate to form cis-aconitic acid as the intermediate compound and catalyze cis-aconitic acid to form isocitric acid. Many TCA cycle intermediates are the precursors for other molecules' synthesis; and NADH (from NAD+) is the major energy that is produced by oxidative steps of the TCA cycle. "
What is the definition of beta-Alanine Metabolism?,"The synthesis of beta-alanine starts with the biosynthesis of S-adenosylmethionine (SAM) from methionine. SAM is then used to synthesized S-adenosylmethionineamine which then reacts with putrescine through a spermidine synthase resulting in the release of 5'-methylthioadenosine and spermidine. The latter compound reacts with S-adenosylmethioninamine through spermine synthase resulting in the release of spermine and 5'-methylthioadenosine. Spermine reacts with water and oxygen through a polyamine oxidase resulting in the release of hydrogen peroxide, spermidine, and 3-aminopropanal. The latter compound reacts with an aldehyde dehydrogenase resulting in the release of beta-alanine. The degradation of beta-alanine leads to the production of coenzyme A which reacts with (R)-pantoate through an ATP-driven pantoate-beta-alanine ligase resulting in the release of pantothenic acid. The latter compound is then phosphorylated through a pantothenate kinase resulting in the release of D-4'-phosphopantothenate. This compound then reacts with L-cysteine and cytidine triphosphate through a phosphopantothenate cysteine ligase resulting in the release of cytidine monophosphate and 4'-phosphopantothenoylcysteine. The latter compound is then decarboxylated through a phosphopantothenoylcysteine decarboxylase resulting in the release of carbon dioxide and 4'-phosphopantethiene. The latter compound is then converted into dephospho-CoA through a pantetheine phosphate adenyltransferase. Dephospho-CoA is finally phosphorylated by a dephospho-CoA kinase resulting in the production of coenzyme A."
What is the definition of 4-Aminobutanoate Degradation ?,"GABA(γ-aminobutyric acid) is a non-protein amino acid that can be accumulated via permease-mediated uptake by Uga4p, Put4p, and Gap1p. GABA can also be produced via glutamate degradation by the glutamate decarboxylase, this variant of the pathway includes a 2-oxoglutarate-dependent 4-aminobutyrate transaminase and an NAD+-dependent dehydrogenase. This combination of enzymes has been documented in bacteria and animals and in some plants. Regarding the hydrogenase, NAD-specific variants have been studied from many bacteria, plant and animals."
What is the definition of Cysteine Metabolism?,"The biosynthesis of cysteine begins with aspartate being phosphorylated into L-aspartyl-4-phosphate through an ATP driven aspartate kinase. L-aspartyl-4-phosphate is then catabolized through an NADPH dependent Aspartic Beta-Semiladehyde dehydrogenase resulting in the release of L-aspartate semialdehyde which is transformed into a homoserine through a Homoserine dehydrogenase. Homeserine in turn is acetylated through a homoserine O-trans-acetylase resulting in the release of O-acetyl-L-homoserine.The latter compound interacts with hydrogen sulfide through a O-acetylhomoserine (thiol)-lyase resulting in the release of L-homocysteine. L-homocysteine reacts with serine through a cystathionine beta synthase resulting in the release of water and L-cystathionine. This compound in turn can be turned into cysteine by reacting with water through a cystathionine gama-lyase. Cysteine can be turned back to L-cystathionine by reacting with a acetyl-L-homoserine spontaneously, thus resulting in L-cystathionine.Cysteine can also be degraded by reacting with a cystathionine gamma lyase resulting in the release of hydrogen sulfide, a hydrogen ion and 2-aminoprop-2-enoate which can spontaneously be converted into 2-iminopropanoate and further degraded into pyruvic acid."
What is the definition of Methionine Metabolism and Salvage?,"The biosynthesis of methionine begins with aspartate being phosphorylated into L-aspartyl-4-phosphate through an ATP driven aspartate kinase. L-Aspartyl-4-phosphate is then catabolized through an NADPH-dependent aspartic beta-semialdehyde dehydrogenase resulting in the release of L-aspartate semialdehyde which is transformed into a homoserine through a homoserine dehydrogenase. Homeserine, in turn, is acetylated through a homoserine O-trans-acetylase resulting in the release of O-acetyl-L-homoserine. The latter compound interacts with hydrogen sulfide through an O-acetylhomoserine (thiol)-lyase resulting in the release of L-homocysteine. The latter compound then reacts with 5-methylterahydropteroyltri-L-glutamate through an N5-methyltetrahydropteroyltrigluatamate homocysteine methyltransferase resulting in the release of a tetrahydropteroyltri-l-glutamate and methionine. The degradation of methionine begins with methionine being used to synthesize S-adenosylmethionine through an S-adenosylmethionine synthetase. The S-adenosylmethionine reacts with a demethylated methyl donor resulting in the release of a methylated methyl donor, a hydrogen ion, and an S-adenosylhomocysteine. The latter compound then reacts with an S-adenosyl-L-homocysteine hydrolase resulting in the release of adenosine and homocysteine where the cycle can begin again. The salvage of methionine begins with S-methyl-5'-thioadenosine (a product of spermine biosynthesis) being phosphorylated through a 5-methylthioadenosine phosphorylase resulting in the release of adenine and S-methyl-5-thio-alpha-D-ribose 1-phosphate. This last compound is isomerized into 5-methylthioribulose 1-phosphate. The latter compound is then dehydrated through a methylthioribulose 1-phosphate dehydratase resulting in 5-(methylthio)-2,3-dioxopentyl 1-phosphate. This resulting compound is then dephosphorylated through a 2,3-dioxomethiopentane-1-phosphate enolase/phosphatase resulting in a  1,2-dihydroxy-5-(methylthio)pent-1-en-3-one. This latter compound can react spontaneously or through an acireductone dioxygenase resulting in the release of a 2-oxo-4-methylthiobutanoate. This latter compound is then turned into methionine through an aromatic amino acid aminotransferase II."
What is the definition of Sarcosine Oncometabolite Pathway ?,"Sarcosine levels have been found to be higher in prostate cancer cells. The expression of sarcosine biosynthetic enzyme, glycine N-methyltransferase (GNMT), is elevated in cancer tissues, while sarcosine dehydrogenase (SARDH) and pipecolic acid oxidase (PIPOX), which metabolize sarcosine, were reduced. Consistent with this, GNMT promoted the oncogenic potential of prostate cells by facilitating sarcosine production, while SARDH and PIPOX reduced the oncogenic potential of prostate cells by metabolizing sarcosine."
What is the definition of Fructose Metabolism?,"The biosynthesis of fructose has multiple point of origin:-Sucrose is metabolized by an invertase resulting in the release of B-D-fructofuranose and D-glucopyranose. D-glucopyranose is then phosphorylated through a ATP driven glucokinase resulting in the release of a hydrogen ion, ADP and D-glucopyranose 6-phosphate. The latter compound is then isomerized through a D-glucopyranose 6-phosphate isomerase resulting in the release of a B-D-fructofuranose 6-phosphate-Sucrose is metabolized by an invertase resulting in the release of B-D-fructofuranose and D-glucopyranose. B-D-fructofuranoseis phosphorylated through an ATP driven fructokinase resulting in the release of B-D-fructofuranose 6-phosphate.-D-sorbitol reacts with sorbitol dehydrogenase resulting in the release of keto-D-fructose.The latter compound reacts spontaneously in B-D-fructofuranose. The latter compound is then phosphorylated through a fructokinase resulting in the release of B-D-fructofuranose 6-phosphate-Sucrose 6-phosphate reacts with an invertase resulting in the release of B-D-fructofuranose and B-D-glucose 6-phosphate. The latter compound is then phosphorylated through a fructokinase resulting in the release of B-D-fructofuranose 6-phosphateThe degradation of B-D-fructofuranose 6-phosphate starts with the phosphorylation of B-D-fructofuranose 6-phosphate through a 6-phosphofructo-2-kinase resulting in the release of B-D-fructose 2,6-bisphosphate that can be latter incorporated into glycolysis"
What is the definition of Mannose Metabolism?,Mannose is metabolized through the phosphorylation of mannose by a mannokinase resulting in a D-mannopyranose 6-phosphate. The latter compound is isomerized into a B-D-fructofuranose 6-phosphate which can either be incorporated into glycolysis or it can be further be metabolized into a mannose 1-phosphate through a phosphomannomutase. Mannose 1-phosphate then react with a gdp and a hydrogen ion to produce GDP-alpha-D-mannose
What is the definition of Glutathione Metabolism?,"The biosynthesis of glutathione starts with Cysteine and Glutamic acid being combined through a glutamate-cysteine ligase resulting in the release of a hydrogen ion, ADP, a phosphate and Gammaglutamylcysteine. The latter compound reacts with a glycine through an ATP dependent glutathione synthase resulting in the release of hydrogen ion, ADP, a phosphate and a glutathione. Glutathione is degraded into cysteinylglycine through a gamma-glutamyltransferase. Cysteinylglycine reacts with water through a cys-gly metaliodipeptidase resulting in the release of glycine and cysteine. L-cysteine reacts with glutamic acid through a glutamate-cysteine ligase resulting in the release of a hydrogen ion, ADP, a phosphate and Gammaglutamylcysteine. The latter compound reacts with a glycine through an ATP dependent glutathione synthase resulting in the release of hydrogen ion, ADP, a phosphate and a glutathione "
What is the definition of Leloir Pathway ?,"The pathway starts with the isomerization of Beta-D-galactose into Alpha-D-galactose through a galactose mutarotase.  Alpha-D-galactose is then phosphorylated through an ATP dependent galactokinase resulting in the release of ADP, a hydrogen ion and alpha-D-galactose 1-phosphate. The latter compound reacts with UDP glucose which is the result of UTP reacting with alpha-D-glucose through a uridinephosphoglucose pyrophosphorylase. The reaction between alpha-D-galactose 1-phosphate and UDP glucose results in the release of glucose 1-phosphate and UDP-alpha-D-galactose.Glucose 1-phosphate can be further isomerized into glucose 6-phosphate, while UDP-alpha-D-galactose can be reverted into UDP glucose through a UDP-epimerase."
What is the definition of Glycine Metabolism?,"The biosynthesis of glycine begins with 3-phospho-D-glycerate being metabolize into 3-phosphohydroxypyruvate through a 3-phosphoglycerate dehydrogenase. The resulting compound 3-phosphohydroxypyruvate is transaminated into 3-phospho-L-serine through a phosphoserine transaminase. This is followed by 3-phospho-L-serine being dephosphorylated through a phosphoserine phosphatase resulting in the release of a phosphate and Serine which can then be used to synthesize glycine through a serine hydroxymethyltransferase.Serine can also be incorporated into the mitochondrion and then serine  can then be used to synthesize glycine through a mitochondrial serine hydroxymethyltransferase. Glycine is then used to synthesize formic acid by first being metabolized into  5,10 methylene THF, which is transformed into a 5,10 methenyltetrahydrofolate , followed by an N10 formyl tetrahydrofolate and lastly formic acid, all through a mitochondrial C1-tetrahydrofolate synthase.Glycine can also be synthesized from threonine through a threonine aldolase resulting in the release of acetaldehyde and glycine.Glycine can also be synthesized from glyoxylate interacting with alanine through a glyoxylate aminotransferase resulting in the release of glycine and pyruvic acid."
What is the definition of Threonine Metabolism?,"The biosynthesis of threonine starts with L-aspartic acid being phosphorylated by an ATP driven Aspartate kinase resulting in an a release of an ADP and an L-aspartyl-4-phosphate. This compound interacts with a hydrogen ion through an NADPH driven aspartate semialdehyde dehydrogenase resulting in the release of a phosphate, an NADP and a L-aspartate-semialdehyde.The latter compound interacts with a hydrogen ion through a NADPH driven aspartate kinase / homoserine dehydrogenase resulting in the release of an NADP and a L-homoserine. L-homoserine is phosphorylated through an ATP driven homoserine kinase resulting in the release of an ADP, a hydrogen ion and a O-phosphohomoserine. The latter compound then interacts with a water molecule threonine synthase resulting in the release of a phosphate and an L-threonine. L-threonine is degraded into glycine and acetaldehyde by reacting with a threonine aldolase. Acetaldehyde can then be integrated into the mitochondria or stay in the cytosol. It is then degraded into Acetyl-CoA through an aldehyde dehydrogenase"
What is the definition of Serine Metabolism?,"The biosynthesis of serine begins with 3-phospho-D-glycerate being metabolize into 3-phosphohydroxypyruvate through a 3-phosphoglycerate dehydrogenase. The resulting compound 3-phosphohydroxypyruvate is transaminated into 3-phospho-L-serine through a phosphoserine transaminase. This is followed by 3-phospho-L-serine being dephosphorylated through a phosphoserine phosphatase resulting in the release of a phosphate and Serine. Serine can also be incorporated into the mitochondrion and then serine  can then be used to synthesize glycine through a mitochondrial serine hydroxymethyltransferase. Glycine is then used to synthesize formic acid by first being metabolized into  5,10 methylene THF, which is transformed into a 5,10 methenyltetrahydrofolate , followed by an N10 formyl tetrahydrofolate and lastly formic acid, all through a mitochondrial C1-tetrahydrofolate synthase.In the cytosol serine can either be degraded to synthesize glycine through a serine hydroxymethyltransferase or it can be degraded into 2-aminoprop-2-enoate. The latter compound can be spontaneously be converted first into 2-iminopropanoate and this compound is then converted into pyruvic acid."
What is the definition of Biosynthesis of Unsaturated Fatty Acids?,"The biosynthesis of unsaturated fatty acids begins with palmitic acid interacting with ATP and Coenzyme A through an acyl-CoA synthetase resulting in the release of AMP, diphosphate and palmitoyl-CoA. This compound then enters the cycle of unsaturated fatty acid elongation This cycle starts with the acyl-CoA reacting with a hydrogen ion and a malonyl-CoA through a 3-oxo-stearoyl-CoA synthase resulting in the release of a coenzyme A, a carbon dioxide molecule and a 3-oxoacyl-CoA. The 3-oxoacyl-CoA then reacts with a hydrogen ion and an NADPH through a 3-oxoacyl-CoA reductase resulting in the release of an NADP and a (3R)-3-hydroxy-acyl-CoA. The resulting compound then reacts with a trans-2-enoyl-CoA hydratase 2 resulting in the release of water and trans-2,3-dehydroacyl-CoA. This compound then reacts with a hydrogen ion and a NADPH through a enoyl-CoA reductase resulting in the release of a NADP and a new acyl-CoA. The cycle goes from palmitoyl-CoA-->stearoyl-CoA-->eicosanoyl-CoA-->docosanoyl-CoA-->tetracosanoyl-CoA-->hexacosanoyl-CoA.The long chain fatty acids  are then incorporated into the sphingolipid pathway. The long chain fatty acid reacts with a phytosphingosine through a ceramide synthase resulting in the release of a hydrogen ion, a coenzyme A and a N-acyl-phytosphinganine."
What is the definition of Glycerol Metabolism?,The glycerol metabolism begins with the reversible reaction of 3-phosphoglyceric acid to glyceric acid through a D-glycerate 3-kinase. Glyceric acid then reacts with a NADH driven aldehyde dehydrogenase resulting in the release of water and glyceraldehyde. Glyceraldehyde is then turned to glycerol through an alcohol dehydrogenase.Glycerol can then either react in a reversible reaction with a glycerol dehydrogenase resulting in the release of dihydroxyacetone.  On the other hand glycerol can be phosphorylated through a glycerol kinase resulting in the release of glycerol 3 phosphate. Both glycerol 3 phosphate and dihydroxyacetone lead to the production of 1-oleyl-2-lyso-phosphatidate. Dihydroxyacetone is then phosphorylated through a dihydroxyacetone kinase resulting in the release of glycerone phosphate. Glycerone phosphate reacts with oleoyl-CoA (an acyl-CoA) through a glycerol-3-phosphate O-acyltransferase resulting in the release of 1-oleoyl-2-lyso-glycerone phosphate. Glycerol 3 phosphate can go back to a glycerol through a glycerol 3-phosphatase. It can also be react with a oleoyl-CoA through a glycerol-3-phosphate O-acyltransferase resulting in the release of 1-oleyl-2-lyso-phosphatidate. This compound reacts with an oleoyl-CoA through a Lysophosphatidic acid:oleoyl-CoA acyltransferase resulting in the release of a dioleoyl phosphatidate
What is the definition of Amino Sugar and Nucleotide Sugar Metabolism?,The metabolism of aminosugars begins with D-fructose being phosphorylated resulting in the release of Beta-D-fructose 6-phosphate. Beta-D-fructose 6-phosphate can react in 3 different paths:1.-Beta-D-fructose 6-phosphate reacts with glucosamine 6-phosphate synthase resulting in the release of glucosamine 6-phosphate. This compound then reacts with glucosamine phosphate N-acetyltransferase resulting in the releaase of N-acetyl-D-Glucosamine 6-phosphate. This compound then reacts with a phosphoacetylglucosamine mutase resulting in the release of N-acetyl-glucosamine 1-phosphate. The latter compound reacts with a UTP through a UDP-N-acetylglucosamine pyrophosphorylase resulting in the release of UDP-N-acetylglucosamine. This compound is then used to produce chiting2.-Beta-D-fructose 6-phosphate reacts with a mannose isomerase to release mannose 6-phosphate. The latter compound then reacts with a phosphomutase resulting in the release of mannose 1-phosphate. This in turn reacts with a GTP through a PSA1 resulting in the release of a guanosine diphosphate mannose.3.-Beta-D-fructose 6-phosphate reacts with a glucose isomerase to release a beta-d-glucose 6 phosphate. This compound reacts wth phosphoglucomutase resulting in the release of glucose 1phosphate. This compound then reacts with a UTP through a uridinephosphoglucose pyrophosphorylase resulting in the release of UDP and a UDP-glucose.  UDP-glucose reacts with a bifunctional protein GAL10 resulting in the release of Uridine diphosphategalactose. This compound reacts in a reversible reaction with glucose 1-phosphate through a Galactose 1-phosphate uridylyltransferase resulting in the release of UDP-glucose and galactose 1-phosphate. 
What is the definition of Tetrahydrofolate Biosynthesis?,"The biosynthesis of tetrahydrofolate begins with guanosine triphosphate interacting with water through  GTP-cyclohydrlase resulting in the release of a formic acid, a hydrogen ion and a dihydroneopterin triphosphate. The latter compound then reacts with water in a spontaneous reaction resulting in the release of pyrophosphate, hydrogen ion and dihydroneopterinphosphate. Dihydroneopterin phosphate then reacts spontaneously with water resulting in the release of phosphate and 7,8-dihydroneopterin. This compound reacts wuth a folic acid synthesis enzyme resulting in the release of glycoaldehyde and 6-hydroxymethyl-7,8-dihydropterin. The latter compound is then diphosphorylated through an ATP driven folic acid synthesis resulting in the release of AMP, a hydrogen ion and 6-hydroxymethyl-7,8-dihydropterin diphosphate. This compound reacts with p-Aminobenzoic acid  that is release from chorismate, the reaction happens through a folic acid synthesis resulting in the pyrophosphate and 7,8-dihydropteric acid. The latter compound reacts with glutamic acid through an ATP driven folic acid synthesis 3 resulting in the release of hydrogen ion, a phosphate, ADP and a 7,8-dihydrofolate monoglutamate. The latter compound reacts with a hydrogen ion through a NADPH through a dihydrofolate reductase resulting in the release of NADP and tetrahydrofolate.  This compound can also be a result of 5,10 methenyltetrahydrofolic acid reacting with water through a mitochondrials c1-tetrahydrofolate synthase which releases a 10-formyltetrahydrofolate. This compound in turn reacts with a 5-phosphoribosyl-N-formylglycinamide through a glycinamide ribotide transformylase resulting in the release of a tetrahydrofolate and a 5'phosphoribosyl-N-fromylglycinamide."
What is the definition of Histidine Biosynthesis?,"The biosynthesis of histidine begins with the transformation of D-ribose 5-phosphate through an ATP-driven pyrophosphokinase resulting in the release of AMP, hydrogen ion, and phosphoribosyl pyrophosphate. The resulting compound then reacts with an ATP phosphoribosyltransferase resulting in the release of pyrophosphate and 1-(5-phosphoribosyl)-ATP. The latter compound then reacts with a histidine biosynthesis bifunctional protein resulting in the release of hydrogen ion, a pyrophosphate and phosphoribosyl-AMP. The resulting compound is then dehydrated through a histidine biosynthesis trifunctional protein resulting in the release of a phosphoribosylformiminoAICAR-phosphate. This compound then reacts with a 1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino] imidazole-4-carboxamide isomerase resulting in the release of a phosphoribulosylformimino-AICAR-P. This resulting compound then reacts with an L-glutamine through a imidazole glycerol phosphate synthase hisHF resulting in the release of glutamic acid, AICAR, hydrogen ion, and D-erythro-imidazoles glycerol phosphate. The latter compound reacts with a imidazoleglycerol-phosphate dehydratase results in the release of a water molecule and imidazole acetol-phosphate. The resulting compound reacts with L-glutamic acid through a histidinol-phosphate aminotransferase resulting in the release of oxoglutaric acid L-histidinol phosphate. Histidinol phosphate reacts with a water molecule through a histidinol-phosphatase resulting in the release of a phosphate and a histidinol. The resulting compound reacts with an NAD driven histidine biosynthesis trifunctional protein resulting in the release of histidinol. Histidinol reacts with water through a histidine biosynthesis trifunctional protein resulting in the release of L-histidine."
What is the definition of Glyoxylate Cycle?,The glyoxylate cycle begins with glyoxylic acid reacting with acetyl-coa through a malate synthase resulting in the release of a L-malic acid. The L-malic acid reacts with an NAD dependent malate dehydrogenase resulting in the release of a oxalacetic acid. This compound in turn reacts with an acetyl-coa through a citrate synthase resulting in the release of citric acid reacts with aconitate hydratase resulting in the release of water molecule and a cis-aconitate. This compound in turn react with a water molecule to produce D-threo-isocitric acid. The resulting compoun then reacts with an isocitrate lyase resulting in the release of a succinic acid and a glyoxylic acid.
What is the definition of Lysine Metabolism?,"The biosynthesis of lysine starts with oxoglutaric acid interacting with acetyl-coa through a homocitrate synthase resulting in the release of homocitric acid. This reaction may happen in the cytosol or in the mitochondria. The homocitric acid spontaneously releases water an is transformed into cis-homoaconitate, The cis-homoaconitate reacts with homoaconitase resulting in the release of water and a homoisocitrate.  Homoisocitrate reacts with a NAD dependent homoisocitrate dehydrogenase resulting in the release of a carbon dioxide, a NADH and a oxoadipic acid. These set of reactions happen in the mitochondria. Oxoadipic acid reacts with a glutamic acid resulting in the release of oxoglutaric acid and aminoadipic acid. The aminoadipic acid reacts with a holo-[LYS2 peptidyl-carrier-protein] through an ATP driven L-2-aminoadipate reductase resulting in the release of AMP, pyrophosphate and L-2-aminoadipyl-[lys2 peptidyl-carrier-protein]. This resulting element reacts with a NADPH dependent L-2-aminoadipate reductase resulting in the release of allysine. Allysine reacts with a glutamic acid through a NADPH dependent saccharopine dehydrogenase resulting in the release of water, NADP and saccharopine. Saccharopine reacts with a water molecule and a NAD dependent saccharopine dehydrogenase resulting in the release of oxoglutaric acid and L-lysine. This last reaction is reversible and leads to the degradation of lysine"
What is the definition of NAD Metabolism?,"The NAD biosynthesis begins with L-tryptophan interacting with oxygen through an indeleoamine 2,3-dioxygenase resulting in the release of N-formylkynurenine. This compound reacts with water through a kynurenine formamidase resulting in the release of formic acid, a hydrogen ion andL-kynurenine. The latter compound reacts with oxygen, hydrogen ion, NADPH through a kynurenine 3-monoxygenase resulting in the release of water, NADP and 3-hydroxy-L-kynurenine. The latter compound reacts with water through a kynureninase resulting in the release of L-alanine, hydrogen ion and 3-hydroxyanthranillic acid. The latter compound reacts with oxygen through a 3-hydroxyanthranilate 3,4-dioxygenase resulting in the release of hydrogen ion and 3-amino-3-carboxymuconic acid semialdehyde. The latter compound then spontaneously releases water and quinolinic acid. Quinolinic acid reacts with PRPP and hydrogen ion through a nicotinate-nucleotide pyrophosphorylase resulting in the release of carbon dioxide, pyrophosphate and nicotinate beta-D-ribonucleotide. Nicotinate beta-D-ribonucleotide can also result from two other set of reactions: a) Nicotinate D-ribonucleoside being phosphorylated through an ATP dependent nicotinamide riboside kinase resulting in the release of ADP, hydrogen ion and nicotinate beta-D-ribonucleotide. b) nicotinamide riboside react with water through uridine nucleosidase resulting in the release of D-Ribose, hydrogen ion and niacinamide. Niacinamide react with water through nicotinamidase resulting in the release of ammonium and nicotinic acid. Nicotinic acid reacts with PRPP , water and ATP through a nicotinate phosphoribosyltransferase resulting in the release of pyrophosphate, ADP, phosphaste and nicotinate beta-D-ribonucleotide.Nicotinate beta-D-ribonucleotide reacts with ATP and hydrogen ion through a nicotinamide/nicotinic acid mononucleotide adenylyltransferase resulting in the release of pyrophosphate and nicotinic acid adenine dinucleotide. The latter compound reacts with glutamine, water, and ATP through a glutamine dependent NAD synthetase resulting in the release of pyrophosphate, AMP, hydrogen ion, glutamic acid and NAD.NAD can also be biosynthesized through a nicotinamide riboside being phosphorylated through an ATP driven nicotinamide riboside kinase resulting in the release of ADP, hydrogen ion and nicotinamide ribotide. The latter compound reacts with ATP and a hydrogen ion through a nicotinamid acid mononucleotide adenylyltransferase resulting in the release of a pyrophosphate and NAD. NAD is degraded through a NAD dependent histone deacetylase resulting in SIR2 resulting in the release of 3-O acetyl ADP-ribose and niacinamide which can be incorporated into the pathway."
What is the definition of Cardiolipin Biosynthesis?,"The biosynthesis of cardiolipin begins in the endoplasmic reticulum. Glycerone phosphate interacts with a NADPH resulting in the release of NADP and glycerol 3-phosphate. Glycerol 3-phoshate reacts with Glycerol-3-phosphate O-acyltransferase resulting in the release of 1-palmitoylglycerol 3-phosphate. The resulting compound reacts with an acyl-CoA through a oleoyl-CoA: lysophosphatidate acyltransferase resulting in the release of a Phosphatidic Acid. Phosphatidic Acid is transported to the mitochondrial outer membrane. Once in, it gets transported into the mitochondrial inner membrane. The phosphatidic acid reacts with cytidine triphosphate through a phosphatidate cytidyltransferase resulting in the release of a CDP-DG. The resulting compound reacts with a glycerol 3-phosphate through a CDP-diacylglycerol-glycerol-3-phosphate 3-phosphatidyltransferase resulting in the release of cytidine monophosphate and PGP. PGP reacts with Phosphatidylglycerophosphatase GEP4, mitochondrial resulting in the release of PG. PG reacts with a CDP-DG through a Cardiolipin synthase (CMP-forming) resulting in the release of CL and cytidine monophosphate. CL reacts with lipase cldp1 resulting in the release of 1-MLCL. This in gets transformed into the isomer 2-MLCL. This in turn can either react with an transacylase TAZ1P resulting in the release of CL or it can be transported to the mitochondrial outer membrane where it reacts with a transacylase TAZ1P resulting in the release of a cardiolipin."
What is the definition of Xylitol Degradation?,"The degradation of xylose begins with NADP dependent trifunctional aldehyde reductase/xylose reductase/glucose 1-dehydrogenase resulting in the release of a NADPH, hydrogen ion and Xylitol. Xylitol reacts with a NAD D-xylulose reductase resulting in the release of NADH, a hydrogen ion and D-xylulose. Xylulose reacts with ATP through a xylulose kinase resulting in a release of ADP, hydrogen ion and xylulose 5-phosphate. The latter compound, xylulose 5-phosphate  through a Ribulose-phosphate 3-epimerase resulting in the release of D-ribulose 5-phosphate. D-ribulose 5-phosphate and xylulose 5-phosphate react with a transketolase resulting in the release of D-glyceraldehyde 3-phosphate  and D-sedoheptulose 7-phosphate. These two compounds react through a transaldolase resulting in the release of a D-erythrose 4-phosphate and Beta-D-fructofuranose 6-phosphate. D-erythrose 4-phosphate reacts with a xylulose 5-phosphate through a transketolase resulting in the release of Beta-D-fructofuranose 6-phosphate and D-glyceraldehyde 3-phosphate"
What is the definition of Phenylalanine Metabolism?,"The biosynthesis of phenylalanine begins with chorismate interacting with chorismate mutase resulting in a prephenate. Prephenate reacts with a hydrogen ion through a prephenate dehydratase resulting in the release of water, carbon dioxide and 2-oxo-3-phenylpropanoate. The latter compound can be turn into phenylalanine through two different reversible reactions a) 2-oxo-3-phenylpropanoate reacts with alanine through a aromatic amino acid aminotransferase 2 resulting in the release of pyruvate and phenylalanine. b) 2-oxo-3-phenylpropanoate reacts with glutamic acid through a amino aci aminotransferase 1 resulting in the release of oxoglutaric acid and phenylalanine. The degradation of phenylalanine begins with the two previous reactions turning phenylalanine back ino 2-oxo-3-phenylpropanoate. The latter compound reacts with a phenylpyruvate carboxy lyase resulting in the release of phenylacetaldehyde. This latter compound reacts with a 2-phenylethanol dehydrogenase resulting in the release of 2-phenylethanol."
What is the definition of Tyrosine Metabolism?,"The biosynthesis of tyrosine begins with chorismate interacting with chorismate mutase resulting in a prephenate. Prephenate reacts with a hydrogen ion through a prephenate dehydratase resulting in the release of NADPH, carbon dioxide and 4-hydroxyphenylpyruvate. The latter compound can be turn into tyrosine through two different reversible reactions a) 4-hydroxyphenylpyruvate reacts with alanine through a aromatic amino acid aminotransferase 2 resulting in the release of pyruvate and phenylalanine. b) 4-hydroxyphenylpyruvatereacts with glutamic acid through a amino aci aminotransferase 1 resulting in the release of oxoglutaric acid and phenylalanine. The degradation of phenylalanine begins with the two previous reactions turning phenylalanine back into 4-hydroxyphenylpyruvate. The latter compound reacts with a phenylpyruvate carboxy lyase resulting in the release of phenylacetaldehyde. This latter compound reacts with a alcohol dehydrogenase resulting in the release of tyrosol."
What is the definition of Tryptophan Metabolism?,"The tryptophan biosynthesis begins with chorismate interacting with a L-glutamine through a Anthranilate synthase resulting in the release of glutamic acid, pyruvic acid, hydrogen ion and 2-aminobenzoic acid. The latter compound reacts with a PRPP through an Anthranilate phosphoribosyltransferase resulting in the release of pyrophosphate and a N-5-phosphoribosyl anthranilate. The latter compound is isomerized through a N-5 phosphoribosylanthranilate isomerase resulting in the release of a 1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate which then reacts with a hydrogen ion resulting in the release of water, carbon dioxide and indoleglycerol phosphate. The latter compound reacts with a tryptophan synthase resulting in the release of D-glyceraldehyde 3-phosphate and Indole. Indole reacts with L-serine through a tryptophan synthase resulting in the release of water and tryptophan.The degradation of tryptophan can occur in 2 ways:a) tryptophan reacting with an aromatic aminotransferase resulting in the release of indole 3 pyruvate which can then be transformed into indoleacetaldehyde through a pyruvate isozyme. Indoleacetaldehyde reacts with alcohol dehydrogenase resulting in a tryptophol B) tryptophan is consumed through the nicotinate biosynthesis"
What is the definition of Riboflavin Metabolism?,"Riboflavin metabolism can happen in two different sets of reactionsa) Guanosine triphosphate reacts with water through a GTP cyclohydrolase resulting in the release of formic acid, pyrophosphate and 2,5-Diamino-6-(1-D-ribosylamino)pyrimidin-4(3H)-one 5'-phosphate. The latter compound then reacts with a NADH dependent  2,5-diamino-6-(ribosylamino)-4(3H)-pyrimidinone 5'-phosphate reductase resulting in the release of NAD and 2,5-Diamino-6-(1-D-ribitylamino)pyrimidin-4(3H)-one 5'-phosphate. The latter compound reacts through a tRNA pseudouridine synthase 8 / 2,5-diamino-6-(5-phospho-D-ribitylamino)-pyrimidin-4(3H)-one deaminase resulting in the release of 5-Amino-2,6-dioxy-4-(5'-phospho-D-ribitylamino)pyrimidine.b)Ribulose 5-phosphate reacts with 3,4-dihydroxy 2-butanone 4-phosphate synthase resulting in the release of formic acid and 1-Deoxy-L-glycero-tetrulose 4-phosphate. The latter compound reacts with a  5-Amino-6-ribitylamino uracil through a 6,7-dimethyl-8-ribityllumazine synthase resulting the release of 6,7-dimethyl-8-(D-ribityl)lumazine. The latter compound reacts with a riboflavin synthase resulting in the release of 5-Amino-6-ribitylamino uracil  and Riboflavin. The Riboflavin reacts with an ATP driven riboflavin synthase resulting in the release of ADP and Flavin mononucleotide. The latter compound reacts with an ATP driven FAD synthetase resulting in the release of pyrophosphate and FAD."
What is the definition of Pyruvate Metabolism?,"The metabolism of pyruvate begins with its biosynthesis which can happen through 5 different sets of reactions.A) Lactaldehyde reacts with an NADPH dependent methylglyoxal reductase results in the release of a pyruvaldehyde. Pyruvaldehyde reacts with glutathione through a lactylglutathione lyase resulting in the release of s-lactoylglutathione. The latter compound then reacts with water through a  hydroxyacylglutathione hydrolase resulting in the release of glutathione and D-lactic acid. Lactic acid then reacts with a ferricytochrome c through a D-lactate dehydrogenase resulting in the release of ferrocytochrome c, a hydrogen ion and pyruvic acid.B) L-lactic acid reacts with a ferricytochrome c through a L-lactate dehydrogenase resulting in the release of ferrocytochrome c, a hydrogen ion and pyruvic acid.C)Phosphoenolpyruvic acid reacts with an ADP through pyruvate kinase II resulting in the release of pyruvic acid. D)Phosphoenolpyruvic acid reacts in a reversible reaction with an ADP or ATP driven phosphoenolpyruvate carboxykinase resulting in the release of oxalacetic acid which reacts with ADP driven pyruvate carboxylase resulting in the release of pyruvic acid.E)L-malic acid reacts in a reversible reaction through NAD driven malate dehydrogenase resulting in the release of pyruvic acid.Pyruvic acid is degraded through 2 sets of reactionsa)Pyruvic acid reacts with a pyruvate decarboxylase resulting in the release of acetaldehyde. This compound then reacts with alcohol dehydrogenase resulting in the release of ethanolb)Pyruvic acid reacts with a Pyruvate dehydrogenase complex resulting in the release of 2-(a-Hydroxyethyl)thiamine diphosphate. The latter compound reacts with a Pyruvate dehydrogenase complex resulting in the release of S-Acetyldihydrolipoamide-E reacts with a Pyruvate dehydrogenase complex resulting in the release of acetyl-CoA. Acetyl CoA can then be metabolized through different reactions to produce the resulting acetate, acetyl adenylate, isopropylmalic acid acetoacetyl coa, malonyl coa or homocitric acid"
What is the definition of Ethanol Fermentation?,"Pyruvic acid can produce ethanol (the ending product of glycolysis pathway) through two-step reactions, and result in ethanol fermentation. Glycolysis is a metabolic pathway with sequence of ten reactions involving ten intermediate compounds that converts glucose to pyruvate. Glycolysis release free energy for forming high energy compound such as ATP and NADH. Glycolysis is consisted of two phases, which one of them is chemical priming phase and second phase is energy-yielding phase. As the starting compound of chemical priming phase, D-glucose can be obtained from galactose metabolism or imported by monosaccharide-sensing protein 1 from outside of cell. D-Glucose is catalyzed by probable hexokinase-like 2 protein to form glucose 6-phosphate which is powered by ATP.  Glucose 6-phosphate transformed to fructose 6-phosphate by glucose-6-phosphate isomerase, which the later compound will be converted to fructose 1,6-bisphosphate, which is the last reaction of chemical priming phase  by 6-phosphofructokinase with cofactor magnesium, and it is also powered by ATP. Before entering the second phase, aldolase catalyzing the hydrolysis of F1,6BP into dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. Dihydroxyacetone phosphate and glyceraldehyde 3-phosphate can convert to each other bidirectionally by facilitation of triosephosphate isomerase. The second phase of glycolysis is yielding-energy phase that produce ATP and NADH. At the first step, D-glyceraldehyde 3-phosphate is catalyzed to glyceric acid 1,3-biphosphate by glyceraldehyde-3-phosphate dehydrogenase with NAD, which also generate NADH. ATP is generated through the reaction that convert glyceric acid 1,3-biphosphate to 3-phosphoglyceric acid. Phosphoglycerate mutase 2 catalyze 3-phosphoglyceric acid to 2-Phospho-D-glyceric acid,  and alpha-enolase with cofactor magnesium catalyzes 2-Phospho-D-glyceric acid to phosphoenolpyruvic acid. Eventually, plastidial pyruvate kinase 4 converts phosphoenolpyruvic acid to pyruvate with cofactor magnesium and potassium and ADP. Pyruvate will undergo pyruvate metabolism, tyrosine metabolism and pantothenate and CoA biosynthesis. "
What is the definition of The Oncogenic Action of L-2-Hydroxyglutarate in Hydroxyglutaric aciduria ?,"Hydroxyglutaric aciduria is a rare genetic disorder. Both isoforms are believed to have autosomal recessive inheritance. The compound 2-hydroxyglutarate is the product of gain-of-function mutations producing mutIDH1 and mutIDH2 in the cytosolic and mitochondrial isoforms of isocitrate dehydrogenase (IDH). This compound is derived from the TCA cycle. The compound 2-hydroxyglutarate shares enough structural similarity to 2-oxogluratate (2OG) to inhibit a range of 2OG-dependent dioxygenases, including histone lysine demethylases (KDMs) and the ten-eleven translocation (TET) family of 5-methylcytosine (5mC) hydroxylases. This results in modulations of HIF-mediated hypoxia responses and alterations in gene expression through global epigenetic remodelling that may contribute to malignant transformation. L-2-hydroxyglutarate dehydrogenase (L2HGDH) converts L-2-hydroxyglutarate to α-ketoglutaric acid. L-2-Hydroxyglutarate is an oncometabolite and is produced by gain-of-function IDH mutations. When IDH is mutated, L-2-Hydroxyglutaric acid production is increased. L-2-hydroxyglutarate is a competitive inhibitor of 2OG-dependent dioxygenases resulting in genetic changes and malignancies. "
What is the definition of The Oncogenic Action of D-2-Hydroxyglutarate in Hydroxyglutaric aciduria ?,"Hydroxyglutaric aciduria  is a rare genetic disorder. Both isoforms are believed to have autosomal recessive inheritance. The compound 2-hydroxyglutarate is the product of gain-of-function mutations producing mutIDH1 and mutIDH2 in the cytosolic and mitochondrial isoforms of isocitrate dehydrogenase (IDH). This compound is derived from the TCA cycle. The compound 2-hydroxyglutarate shares structural similarity with 2-oxogluratate (2OG) to inhibit a range of 2OG-dependent dioxygenases, including histone lysine demethylases (KDMs) and the ten-eleven translocation (TET) family of 5-methylcytosine (5mC) hydroxylases. This results in modulations of HIF-mediated hypoxia responses and alterations in gene expression through global epigenetic remodelling that may contribute to malignant transformation. 2-Hydroxyglutarate dehydrogenase (D2HGDH) converts D-2-hydroxyglutarate (D-2HG) to α-ketoglutaric acid. The enzyme D-3-phosphoglycerate dehydrogenase (PHGDH) catalyzes the NADH-dependent reduction of α-ketoglutarate (AKG) to D-2HG.  D-2-Hydroxyglutarate is an oncometabolite produced from IDH mutations.  A mutation in IDH causes high concentrations of D-2-Hydroxyglutaric acid. D-2-hydroxyglutarate is a competitive inhibitor of 2OG-dependent dioxygenases resulting in genetic changes and malignancies. "
What is the definition of Fatty Acid Biosynthesis ?,"he entire synthesis process which produces palmitic acid occurs on a multifunctional dimeric protein Fatty Acid Synthase (FA) in the cytosol. The production of palmitic acid can be summarized as the successive addition of two carbons to an initial acetyl moiety primer. After 7 cycles palimitic acid is released. The synthesis starts with the sequential transfer of a primer substrate, acetyl-CoA, to the nucleophilic serine residue of the acyltransferase domain of FA. The acetyl moiety is then transferred to the Acyl Carrier Protein (ACP) domain of FA, then finally to the active site of the beta-ketoacyl synthase domain. A chain extender substrate, molonyl-CoA, is transferred to the nucleophilic serine residue of the acyltransferase domain and subsequently to the ACP domain. The acetyl moiety is extend by a condensation reaction, catalysed by the beta-ketoacyl synthase domain, that produces a new Carbon-Carbon bound, this reaction is coupled to a decarboxylation resulting in the production of carbon dioxide. Subsequently beta-ketoacyl condensation product is reduced to a saturated acyl moiety through the step wise action on the beta-ketoacyl reductase, beta-hydroxyacyl dehydrase and enoyl reductase domains respectively. This saturated acyl moiety is then transfer back to the active site of the beta-ketoacyl synthase domain, another molonyl-CoA is loaded and the process repeats. The addition of molonyl moieties occurs 7 times after which the final product is released by that action of thioesterase domain. The final product is 16 carbon long palmitic acid."
What is the definition of Oxidative Phosphorylation?,"The process of oxidative phosphorylation involves multiple interactions of ubiquinone with succinic acid, resulting in a fumaric acid and ubiquinol. Ubiquinone interacts with succinic acid through a succinate:quinone oxidoreductase resulting in a fumaric acid an ubiquinol. This enzyme has various cofactors, ferroheme b, 2FE-2S, FAD, and 3Fe-4S iron-sulfur cluster. Then 2 ubiquinol interact with oxygen and 4 hydrogen ion through a cytochrome bd-I terminal oxidase resulting in a 4 hydrogen ion transferred into the periplasmic space, 2 water returned into the cytoplasm and 2 ubiquinone, which stay in the inner membrane. The ubiquinone interacts with succinic acid through a succinate:quinone oxidoreductase resulting in a fumaric acid an ubiquinol. Then 2 ubiquinol interacts with oxygen and 4 hydrogen ion through a cytochrome bd-II terminal oxidase resulting in a 4 hydrogen ion transferred into the periplasmic space, 2 water returned into the cytoplasm and 2 ubiquinone, which stay in the inner membrane. The ubiquinone interacts with succinic acid through a succinate:quinone oxidoreductase resulting in a fumaric acid an ubiquinol. The 2 ubiquinol interact with oxygen and 8 hydrogen ion through a cytochrome bo terminal oxidase resulting in a 8 hydrogen ion transferred into the periplasmic space, 2 water returned into the cytoplasm and 2 ubiquinone, which stays in the inner membrane. The ubiquinone then interacts with 5 hydrogen ion through a NADH dependent ubiquinone oxidoreductase I resulting in NAD, hydrogen ion released into the periplasmic space and an ubiquinol. The ubiquinol is then processed reacting with oxygen, and 4 hydrogen through a ion cytochrome bd-I terminal oxidase resulting in 4 hydrogen ions released into the periplasmic space, 2 water molecules into the cytoplasm and 2 ubiquinones. The ubiquinone then interacts with 5 hydrogen ion through a NADH dependent ubiquinone oxidoreductase I resulting in NAD, hydrogen ion released into the periplasmic space and an ubiquinol. The 2 ubiquinol interact with oxygen and 8 hydrogen ion through a cytochrome bo terminal oxidase resulting in a 8 hydrogen ion transferred into the periplasmic space, 2 water returned into the cytoplasm and 2 ubiquinone, which stays in the inner membrane. "
What is the definition of Porphyrin Metabolism ?,"Porphyrins are organic compounds. Many porphyrins are involved in oxygen transportation. Porphyrin ring biosynthesis begins in the mitochondria and involves glycine and succinyl-CoA condensation by δ-aminolevulinic acid synthase (ALAS) to produce δ-aminolevulinic acid (ALA), also known as 5-aminolevulinic acid. ALA is then transported to the cytosol where it becomes dimerized by ALA dehydratase (also known as porphobilinogen synthase) to produce porphobilinogen. The pathway continues with the condensation of 4 molecules of porphobilinogen catalyzed by porphobilinogen deaminase (PBG deaminase, also called hydroxymethylbilane synthase or uroporphyrinogen I synthase) to produce hydroxymethylbilane. Hydroxymethylbilane may then be converted to uroporphyrinogen III, a heme intermediate, or it may be non-enzymatically cyclized to uroporphyrinogen I. In the cytosol, uroporphyrinogen I and III substituents become decarboxylated to become coproporphyrinogens. Coproporphyrinogen III is an important intermediate in the synthesis of heme. In the inner mitochondria, coproporphyrinogen III undergoes decarboxylation of 2 propionate residues producing protoporphyrinogen IX. Protoporphyrinogen IX oxidase converts protoporphyrinogen IX to protoporphyrin IX. The final reaction of heme synthesis is ferrochelatase catalyzing the insertion of iron into the ring, producing heme b. Heme is broken down when heme oxygenase opens the heme ring. This oxidation produces linear tetrapyrrole biliverdin, ferric iron (Fe3+), and carbon monoxide (CO). Biliverdin reductase then produces bilirubin. "
What is the definition of Pantothenate and CoA Biosynthesis ?,"CoA biosynthesis requires compounds from two other pathways: aspartate metabolism and valine biosynthesis. It requires a beta-alanine and R-pantoate. The compound (R)-pantoate is generated in two reactions, as shown by the interaction of alpha-ketoisovaleric acid, 5,10 methylene-THF, and water through a 3-methyl-2-oxobutanoate hydroxymethyltransferase resulting in a tetrahydrofolic acid and a 2-dehydropantoate. This compound interacts with hydrogen through an NADPH-driven acetohydroxy acid isomeroreductase resulting in the release of NADP and R-pantoate. On the other hand L-aspartic acid interacts with a hydrogen ion and gets decarboxylated through an aspartate 1-decarboxylase resulting in a carbon dioxide and a beta-alanine. beta-Alanine and R-pantoate interact with an ATP-driven pantothenate synthetase resulting in pyrophosphate, AMP, hydrogen ion, and pantothenic acid. Pantothenic acid is phosphorylated through an ATP-driven pantothenate kinase resulting in an ADP, a hydrogen ion, and D-4'-phosphopantothenate. This compound interacts with a CTP and a L-cysteine resulting in a fused 4'-phosphopantothenoylcysteine decarboxylase and phosphopantothenoylcysteine synthetase resulting in a hydrogen ion, a pyrophosphate, a CMP,  and 4-phosphopantothenoylcysteine. The latter compound interacts with a hydrogen ion through a fused 4'-phosphopantothenoylcysteine decarboxylase and phosphopantothenoylcysteine synthetase resulting in a carbon dioxide release and a 4-phosphopantetheine. This compound interacts with an ATP, hydrogen ion, and a phosphopantetheine adenylyltransferase resulting in a release of pyrophosphate, and dephospho-CoA. Dephospho-CoA reacts with an ATP driven dephospho-CoA kinase resulting in an ADP, a hydrogen ion, and a coenzyme A. Coenzyme A is converted by beta-alanine ligase and a kinase to (R)-4'-phosphopantothenate. These kinases are inhibited by negative feedback by CoA, this is the primary regulation of CoA biosynthesis. L-cysteine is added to (R)-4'-phosphopantothenate to form R-4'-phosphopantothenoyl-L-cysteine (PPC). PPC is then decarboxylated to 4'-phosphopantetheine then converted to CoA by a dephospho-CoA Kinase. The enzymes of this pathway are necessary for growth. "
What is the definition of Fatty Acid Elongation In Mitochondria ?,"Cells typically contain large amounts of C18 and C20 fatty acids. Longer chain fatty acids are derived from either dietary sources or from elongation of C16-CoA or C18-CoA formed by the cytoplasmic fatty acid synthetase system. All of the fatty acids needed can be synthesized from palmitate (C16:0) except the essential polyunsaturated fatty acids such as linoleate and linolenate. To create longer, shorter, oxidized, reduced fatty acids, palmitic acid is subjected to enzymatic reactions by reductases, hydroxylases, elongases and mixed function oxidases. There are 3 major processes that modify palmitic acid: elongation, desaturation, and hydroxylation. Elongation of fatty acids may occur at endoplasmic reticulum where fatty acid molecules of length up to C24 may be produced. Mitochondrial elongation may result in fatty acids up to C16 in length. Fatty acid elongation in mitochondria is essentially the reverse of beta-oxidation for fatty acid oxidation. In particular, both pathways make use of acetyl-CoA acyltransferase, 3-hydroxyacyl-CoA dehydrogenase and enoyl-CoA hydratase. The final step of fatty acid elongation uses enoyl-CoA reductase (not part of the beta-oxidation pathway). The mitochondrial pathway is important for elongating fatty acids containing 14 or fewer carbon atoms. Fatty acids with aliphatic tails of less than six carbons are short-chain fatty acids (SCFA). Medium chains (MCFA) have a six to twelve carbon tail and large chains (LCFA) have a tail with greater than twelve carbons. Very long chain fatty acids (VLCFA) have a tail with greater than twenty-two carbons. "
What is the definition of One Carbon Pool by Folate I ?,"Dihydrofolic acid, a product of the folate biosynthesis pathway, can be metabolized by multiple enzymes. Dihydrofolic acid can be reduced by a NADP-driven dihydrofolate reductase resulting in a NADPH, hydrogen ion and folic acid. Dihydrofolic acid can also be reduced by an NADPH-driven dihydrofolate reductase resulting in a NADP and a tetrahydrofolic acid. Folic acid can also produce a tetrahydrofolic acid through a NADPH-driven dihydrofolate reductase. Dihydrofolic acid also interacts with 5-thymidylic acid through a thymidylate synthase resulting in the release of dUMP and 5,10-methylene-THF Tetrahydrofolic acid can be converted into 5,10-methylene-THF through two different reversible reactions. Tetrahydrofolic acid interacts with a S-Aminomethyldihydrolipoylprotein through a aminomethyltransferase resulting in the release of ammonia, a dihydrolipoylprotein and 5,10-Methylene-THF Tetrahydrofolic acid interacts with L-serine through a glycine hydroxymethyltransferase resulting in a glycine, water and 5,10-Methylene-THF. The compound 5,10-methylene-THF reacts with an NADPH dependent methylenetetrahydrofolate reductase [NAD(P)H] resulting in NADP and 5-Methyltetrahydrofolic acid. This compound interacts with homocysteine through a methionine synthase resulting in L-methionine and tetrahydrofolic acid. Tetrahydrofolic acid can be metabolized into 10-formyltetrahydrofolate through 4 different enzymes: 1.- Tetrahydrofolic acid interacts with FAICAR through a phosphoribosylaminoimidazolecarboxamide formyltransferase resulting in a 1-(5'-Phosphoribosyl)-5-amino-4-imidazolecarboxamide and a 10-formyltetrahydrofolate 2.-Tetrahydrofolic acid interacts with 5'-Phosphoribosyl-N-formylglycinamide through a phosphoribosylglycinamide formyltransferase 2 resulting in a Glycineamideribotide and a 10-formyltetrahydrofolate 3.-Tetrahydrofolic acid interacts with Formic acid through a formyltetrahydrofolate hydrolase resulting in water and a 10-formyltetrahydrofolate 4.-Tetrahydrofolic acid interacts with N-formylmethionyl-tRNA(fMet) through a 10-formyltetrahydrofolate:L-methionyl-tRNA(fMet) N-formyltransferase resulting in a L-methionyl-tRNA(Met) and a 10-formyltetrahydrofolate 10-formyltetrahydrofolate can interact with a hydrogen ion through a bifunctional 5,10-methylene-tetrahydrofolate dehydrogenase resulting in water and 5,10-methenyltetrahydrofolic acid. Tetrahydrofolic acid can be metabolized into 5,10-methenyltetrahydrofolic acid by reacting with a 5'-phosphoribosyl-a-N-formylglycineamidine through a phosphoribosylglycinamide formyltransferase 2 resulting in water, glycineamideribotide and 5,10-methenyltetrahydrofolic acid. The latter compound can either interact with water through an aminomethyltransferase resulting in a N5-Formyl-THF, or it can interact with a NADPH driven bifunctional 5,10-methylene-tetrahydrofolate dehydrogenase resulting in a NADP and 5,10-Methylene THF."
What is the definition of Selenocompound Metabolism?,The the metabolism of selenocompounds starts with Selenocysteine being metabolized by a CGS resulting in the release of Seleno-cystathionine. The resulting compound is metabolized by a CBL resulting in the release of selenohomocysteine. The resulting compound reacts with MET resulting in the release of a seleno-methionine. Selenomethionine can be either metabolized into Seleno-methionyl-tRNA or a Methyl-selenol. Methyl-selenol can also be the result of Methyl-selenic acid reacting with a thioredoxin reductase or Se-methyl-selenocysteine reacting through a CTH.
What is the definition of Valine Biosynthesis ?,"The pathway of valine biosynthesis starts with pyruvic acid interacting with a hydrogen ion through a acetolactate synthase / acetohydroxybutanoate synthase or a acetohydroxybutanoate synthase / acetolactate synthase resulting in the release of carbon dioxide and (S)-2-acetolactate. The latter compound then interacts with a hydrogen ion through an NADPH driven acetohydroxy acid isomeroreductase resulting in the release of a NADP and an (R) 2,3-dihydroxy-3-methylvalerate. The latter compound is then dehydrated by a dihydroxy acid dehydratase resulting in the release of water and isovaleric acid. Isovaleric acid interacts with an L-glutamic acid through a Valine Transaminase resulting in a oxoglutaric acid and an L-valine."
What is the definition of Isoleucine Biosynthesis ?,"Isoleucine biosynthesis begins with L-threonine from the threonine biosynthesis pathway. L-threonine interacts with a threonine dehydratase biosynthetic releasing water, a hydrogen ion and (2Z)-2-aminobut-2-enoate. This compound is isomerized into a 2-iminobutanoate which interacts with water and a hydrogen ion spontaneously, resulting in the release of ammonium and 2-ketobutyric acid. This compound reacts with pyruvic acid and hydrogen ion through an acetohydroxybutanoate synthase / acetolactate synthase 2 resulting in carbon dioxide and (S)-2-Aceto-2-hydroxybutanoic acid. The latter compound is reduced by an NADPH driven acetohydroxy acid isomeroreductase releasing NADP and acetohydroxy acid isomeroreductase. The latter compound is dehydrated by a dihydroxy acid dehydratase resulting in 3-methyl-2-oxovaleric acid.This compound reacts in a reversible reaction with L-glutamic acid through a Branched-chain-amino-acid aminotransferase resulting in oxoglutaric acid and L-isoleucine."
What is the definition of Sphingolipid Metabolism ?,"Sphingolipids have important structural and functional roles. They can be associated with membrane cholesterol and assist in forming specialized membrane domains. Sphingolipids, similar to phospholipids, have a polar head group with two nonpolar tails. Sphingolipids differ from phospholipids by their sphingosine core, a long-chain amino alcohol. sphingomyelins and glycosphingolipids are sphingolipids.  Sphingolipids are produced in the endoplasmic reticulum. Sphinoglipid synthesis begins with palmitoyl-CoA and serine producing 3-keto-dihydrosphingosine by serine palmitoyltransferase. 3-Keto-dihydrosphingosine is then reduced to dihydrosphingosine which is then acylated to form dihydroceramide. Dihydroceramide is then dehyrogenated to ceramide. Ceramides are a sphingosine and fatty acid connected by an amide bond and can be produced by metabolism of sphingolipids. Ceramide can also be broken down back to sphingosine. Ceramide gets transported to the Golgi where it forms sphingomyelin or glycosphingolipids. From the Golgi, these products are transported by vesicles to specialized membrane domains. "
What is the definition of Taurine and Hypotaurine Biosynthesis?,"The biosynthesis of taurine and hypotaurine is processed by the same protein, glutamate decarboxylase. Hypotaurine is produced by 3-sulfino-L-alanine reacting with glutamate decarboxylase resulting in the release of carbon dioxide and hypotaurine. Taurine is produced by L-cysteate reacting with a glutamate decarboxylase resulting in the release of Taurine and carbon dioxide"
What is the definition of Starch and Sucrose Metabolism ?,"Carbohydrates are a major component of the diet, and include starch (amylose and amylopectin) and disaccharides such as sucrose, lactose, maltose and, in small amounts, trehalose. Once released from starch or once ingested, sucrose can be degraded into beta-D-fructose and alpha-D-glucose via lysosomal alpha-glucosidase or sucrose-isomaltase. Beta-D-Fructose can be converted to beta-D-fructose-6-phosphate by glucokinase and then to alpha-D-glucose-6-phosphate by the action of glucose phosphate isomerase. Phosphoglucomutase 1 can then act on alpha-D-glucose-6-phosphate (G6P) to generate alpha-D-glucose-1-phosphate. alpha-D-Glucose-1-phosphate (G6P) has several possible fates. It can enter into gluconeogenesis, glycolysis, or the nucleotide sugar metabolism pathway. UDP-glucose pyrophosphorylase 2 can convert alpha-D-glucose-1-phosphate into UDP-glucose, UDP-glucose can then be used to produce D-glucose via trehalose. UDP-glucose can also serve as a precursor to the synthesis of glycogen via glycogen synthase. Glycogen is a starch analogue commonly called an animal starch. Glycogen is found in the cytosol in granules. Glycogen is cleaved and converted to glucose-6-phosphate (G6P) which undergoes glycolysis or can enter the pentose phosphate pathway. "
What is the definition of Steroid Biosynthesis ?,"The biosynthesis of steroids begins with acetyl coa being turned into acetoacetyl through a acetoacetyl CoA thiolase. Acetoacetyl -CoA reacts with an acetyl-CoA and water through a 3-hydroxy 3-methylglutaryl coenzyme A synthase resulting in the release of coenzyme A, hydrogen ion and (S)-3-hydroxy-3-methylglutaryl-CoA. The latter compound reacts with NADPH and a hydrogen ion through a 3-hydroxy-3-methylglutaryl-coenzyme A resulting in the release of coenzyme A , NADP and mevalonate. Mevalonate is then phosphorylated through an ATP  driven kinase mevalonate kinase resulting in the release of ADP, hydrogen ion and mevalonate 5-phosphate. The latter compound is phosphorylated through an ATP driven kinase, phosphomevalonate kinase resulting in the release of ADP and mevalonate diphosphate. This latter compound then reacts with an ATP driven mevalonate diphosphate decarboxylase resulting in the release of ADP, carbon dioxide, a phosphate and a isopentenyl diphosphate. The latter compound can be isomerized into dimethylallyl diphosphate or reacth with a dimethylallyl diphosphate to produce geranyl diphosphate. Geranyl diphosphate reacts with a isopentenyl through a farnesyl diphosphate synthase resulting in the release of diphosphate and farnesyl diphosphate. The latter compound reacts with hydrogen ion, NADPH through a squalene synthetase resulting in the release NADP, pyrophosphate and squalene. The latter compound reacts with hydrogen ion NADPH and oxygen through squalene monooxygenase resulting in the release of NADP, Water and  (3S)-2,3-epoxy-2,3-dihydrosqualene. The latter compound reacts through a 2,3-oxidosqualene lanosterol cyclase resulting in the release of lanosterol. Lanosterol reacts with  hydrogen ion, NADPH, and oxygen through a cytochrome P450 lanosterol 14a demethylase resulting in the release of formate, water, NADP and 14-demethyllanosterol. The latter compound reacts with hydrogen ion and NADPH through a c-14 sterol reductase resulting in the release of NADP and 4,4-dimethylzymosterol. The latter compound reacts with methylsterol monooxygenase resulting in the release of 4α-hydroxymethyl-4β-methyl-5α-cholesta-8,24-dien-3β-ol which reacts with methylsterol monooxygenase twice to obtain 4α-carboxy-4β-methyl-5α-cholesta-8,24-dien-3β-ol. The latter compound then reacts with an NADP C-3 sterol dehydrogenase resulting in the release of water, NADP and 3-dehydro-4-methylzymosterol. The latter compound then reacts with NADPH and a hydrogen ion through a 3-keto sterol reductase resulting in the release of NADP and 4alpha-methyl-zymosterol. The latter compound then reacts with a methylsterol monooxygenase 3 times, followed by one reaction with c-sterol dehydrogenase and one reaction with 3-keto sterol reductase resulting in the release of a zymosterol. The latter compound reacts with SAM through a sterol methyltransferase resulting in the release of s-adenosylhomocysteine and fecosterol. Fecosterol is isomerized into episterol. The latter compound reacts with c-5 sterol desaturase resulting in the release of ergosta-5,7,24(28)-trien-3β-ol which then reacts with a c-22 sterol desaturase resulting in the release of  ergosta-5,7,22,24(28)-tetraen-3-β-ol. This latter compound then reacts with a C-24 sterol reductase resulting in the release of an ergosterol.	"
What is the definition of Sulfur Metabolism?,"The sulfur metabolism pathway starts in three possible ways. Sulfate is converted by the sulfate adenylyltransferase enzymatic complex to adenosine phosphosulfate through the addition of adenine from a molecule of ATP, along with one phosphate group. Adenosine phosphosulfate is further converted to phoaphoadenosine phosphosulfate through an ATP hydrolysis and dehydrogenation reaction by the adenylyl-sulfate kinase. Phoaphoadenosine phosphosulfate is finally dehydrogenated and converted to sulfite by phosphoadenosine phosphosulfate reductase. This reaction requires magnesium, and adenosine 3',5'-diphosphate is the bi-product. A thioredoxin is also oxidized. Sulfite next undergoes a series of reactions that lead to the production of pyruvic acid, which is a precursor for pathways such as gluconeogenesis. The first reaction in this series is the conversion of sulfite to hydrogen sulfide through hygrogenation and the deoxygenation of sulfite to form a water molecule. The reaction is catalyzed by the sulfite reductase [NADPH] flavoprotein alpha and beta components. Siroheme, 4Fe-4S, flavin mononucleotide, and FAD function as cofactors or prosthetic groups. Hydrogen sulfide next undergoes dehydrogenation in a reversible reaction to form L-Cysteine and acetic acid, via the cysteine synthase complex and the coenzyme pyridoxal 5'-phosphate. On the other hand L-cysteine can also be formed through homocysteine. L-Cysteine is dehydrogenated and converted to 2-aminoacrylic acid (a bronsted acid) and hydrogen sulfide(which may be reused) by a larger enzymatic complex composed of cysteine synthase A/B, protein malY, cystathionine-β-lyase, and tryptophanase, along with the coenzyme pyridoxal 5'-phosphate. 2-aminoacrylic acid isomerizes to 2-iminopropanoate, which along with a water molecule and a hydrogen ion is lastly converted to pyruvic acid and ammonium in a spontaneous fashion. The second possible initial starting point for sulfur metabolism is taurine(an alternate sulfur source oxoglutaric acid, and oxygen are converted to sulfite by the alpha-ketoglutarate-dependent taurine dioxygenase. Carbon dioxide, succinic acid, and aminoacetaldehyde are bi-products of this reaction. Sulfite next enters pyruvic acid synthesis as already described. The third variant of sulfur metabolism starts with thiosulfate releasing  Sulfite is next converted to pyruvic acid by the process already described. "
What is the definition of Ketone Body Metabolism ?,The ketone body metabolism is a simple pathway that shows a reversible reaction from acetoacetyl-Coa to acetyl-CoA. Both are combined to form S-3-hydroxy-3-methylglutaryl-CoA. The latter compound can then be incorporated into the steroid biosynthesis pathway.
What is the definition of Terpenoid Backbone Biosynthesis?,"The biosynthesis of steroids begins with acetyl coa being turned into acetoacetyl through a acetoacetyl CoA thiolase. Acetoacetyl -CoA reacts with an acetyl-CoA and water through a 3-hydroxy 3-methylglutaryl coenzyme A synthase resulting in the release of coenzyme A, hydrogen ion and (S)-3-hydroxy-3-methylglutaryl-CoA. The latter compound reacts with NADPH and a hydrogen ion through a 3-hydroxy-3-methylglutaryl-coenzyme A resulting in the release of coenzyme A , NADP and mevalonate. Mevalonate is then phosphorylated through an ATP driven kinase mevalonate kinase resulting in the release of ADP, hydrogen ion and mevalonate 5-phosphate. The latter compound is phosphorylated through an ATP driven kinase, phosphomevalonate kinase resulting in the release of ADP and mevalonate diphosphate. This latter compound then reacts with an ATP driven mevalonate diphosphate decarboxylase resulting in the release of ADP, carbon dioxide, a phosphate and a isopentenyl diphosphate. The latter compound can be isomerized into dimethylallyl diphosphate or reacth with a dimethylallyl diphosphate to produce geranyl diphosphate. Geranyl diphosphate reacts with a isopentenyl through a farnesyl diphosphate synthase resulting in the release of diphosphate and farnesyl diphosphate. Farnesyl diphosphate has three different fates: 1.-Producing hexaprenyl diphosphate in the mitocondrial inner membrane by reacting with 3 isopentenyl diphosphate2.-Producing geranylgeranyl diphosphate in the cytoplasm by reacting with one isopentenyl diphosphate3.-Producing a dolichol precursor in the ER by reacting with 13 isopentenyl diphosphates."
What is the definition of Vitamin B1/Thiamine Metabolism?,"The biosynthesis of thiamine begins with pyrithiamine reacting with thiaminase 2 resulting in the release of 4-Amino-5-hydroxymethyl-2-methylpyrimidine. The latter compound reacts with a hydroxymethylpyrimidine/phosphomethylpyrimidine kinase resulting in the release of 4-amino-2-methyl-5-phosphomethylpyrimidine. The latter compound reacts with a hydroxymethylpyrimidine/phosphomethylpyrimidine kinase resulting in the release of 2-Methyl-4-amino-5-hydroxymethylpyrimidine diphosphate. The latter compound reacts with 4-methyl-5-(2-phosphonooxyethyl)thiazole, a product of oxythiamine metabolism, through a Thiamine biosynthetic bifunctional enzyme resultin in the release of a Thiamine monophosphate. The latter compound is phosphatased through a acid phosphatase complex resulting in the release of thiamine. The latter compound is phosphorylated through a thiamin pyrophosphokinase resulting in the release of thiamine pyrophosphate."
What is the definition of Vitamin B6?,"Vitamin B6 belongs to the vitamin B complex group and is water-soluble. The active form is Pyridoxal phosphate (PLP) which acts as a cofactor for various essential enzymes in reactions including: amino acid metabolism, transamination, deamination, and decarboxylation. Other forms of the vitamin include: pyridoxine (PN), pyridoxine 5’-phosphate (PNP), pyridoxal (PL), pyridoxamine (PM), pyridoxamine 5’-phosphate (PMP), and 4-pyridoxic acid (PA). Most animals are unable to synthesize the vitamin while most bacteria are able too. Some organisms also import the vitamin to supplement or augment biosynthesis. S. cerevisiae has transporter Tpn1p on the plasma membrane to import vitamin B6. It transports mostly PN, a precursor of PLP, but also PM and PL. Vitamin B6 is also an antioxidant to provide protection against reactive oxygen species. It has been shown that vitamin B6 synthesis is increased in response to cell stress. "
What is the definition of Valine Degradation?,The degradation of valine starts either in the mitochondria or the cytosol. L-valine reacts with 2-oxoglutarate through a branch-chain amino acid aminotransferase resulting in the release of L-glutamate and 3-methyl-2-oxobutanoate. The latter compound reacts with 2-oxoisovalerate carboxy-lyase resulting in the release of carbon dioxide and isobutanal. Isobutanal can then be turned into isobutanol through a alcohol dehydrogenase
What is the definition of Leucine Degradation?,The degradation of L-leucine starts either in the mitochondria or the cytosol. L-leucine reacts with 2-oxoglutarate through a branch-chain amino acid aminotransferase resulting in the release of ketoleucine and glutamate. The latter compound reacts with ketoisocaproate decarboxylase resulting in the release of carbon dioxide and 3-methylbutanal. The latter compound can then be turned into 3-methylbutanol through a alcohol dehydrogenase
What is the definition of Isoleucine Degradation?,The degradation of isoleucine starts either in the mitochondria or the cytosol. L-isoleucine reacts with 2-oxoglutarate through a branch-chain amino acid aminotransferase resulting in the release of L-glutamate and 3-methyl-2-oxopentanoate. The latter compound reacts with 2-oxoisovalerate carboxy-lyase resulting in the release of carbon dioxide and methylbutanal. Methylbutanal can then be turned into methylbutanol through a alcohol dehydrogenase
What is the definition of Ether Lipid Metabolism?,"The metabolism of ether lipids can begin with 1-O-Hexadecyl-2-O-acetyl-sn-glycerol and citicoline reacting through a CPT1 resulting in the release of CMP, 2-acetyl-1-alkyl-sn-glycerol-3-phosphocholine (PAF), in this case, a 2-acetyl-1-hexadecyl-sn-glycero-3-phosphocholine. The latter compound reacts with a cytidine monophosphate through a platelet-activating factor acetylhydrolase IB subunit alpha resulting in the release of acetic acid, hydrogen ion and lysoPAF.   The latter compound can react with a palmitic acid reacting with TAG lipase / steryl ester hydrolase / phospholipase A2 / LPA acyltransferase resulting in the release of water and 1-O-Palmityl-2-palmitoyl-rac-glycero-3-phosphocholine. The latter compound can also be generated by  1-O-Hexadecyl-2-palmitoyl-sn-glycerol reacting with citicoline through a diacylglycerol cholinephosphotransferase resulting in the release of 1-O-Palmityl-2-palmitoyl-rac-glycero-3-phosphocholine and Cytidine monophosphate.  1-O-Hexadecyl-2-palmitoyl-sn-glycerol reacts with CDP-Ethanolamine through a  bifunctional diacylglycerol cholinephosphotransferase/ethanolaminephosphotransferase resulting in the release of 1-hexadecyl-2-palmitoyl-glycero-3-phosphoethanolamine  and Cytidine monophosphate"
What is the definition of Glycerophospholipid Metabolism?,The metabolism of glycerophospholipid begins with glycerone phosphate either reacting with glycerol-3-phosphate dehydrogenase resulting in the release of glycerol-3-phosphate or it can react with glycerol-3-phosphate O-acyltransferase / dihydroxyacetone phosphate acyltransferase resulting in the release of a 1-acylglycerone 3-phosphate. Glycerol-3-phosphate reacts with glycerol-3-phosphate O-acyltransferase resulting in the release of an acyl glycerol phosphate. 1-acylglycerone 3-phosphate 1-acyl dihydroxyacetone phosphate reductase resulting in the release of a acyl glycerol phosphate. The latter compound then reacts with a oleoyl-CoA: lysophosphatidate acyltransferase resulting in the release of a phosphatidic acid. The latter compound reacts with Phosphatidic acid phosphohydrolase 1 resulting in the release of diacyl glycerol. This compound can be metabolized through a CTP-dependent diacylglycerol kinase 1 resulting in the release of a phosphatidic acid. Diacyl glycerol reacts with cdp-ethanolamine through a bifunctional diacylglycerol cholinephosphotransferase/ethanolaminephosphotransferase resulting in the release of a phosphatidyl ethanolamine.
What is the definition of Choline Metabolism?,The metabolism of choline containing lipids begins with glycerone phosphate either reacting with glycerol-3-phosphate dehydrogenase resulting in the release of glycerol-3-phosphate or it can react with glycerol-3-phosphate O-acyltransferase / dihydroxyacetone phosphate acyltransferase resulting in the release of a 1-acylglycerone 3-phosphate. Glycerol-3-phosphate reacts with glycerol-3-phosphate O-acyltransferase resulting in the release of an acyl glycerol phosphate. 1-acylglycerone 3-phosphate 1-acyl dihydroxyacetone phosphate reductase resulting in the release of a acyl glycerol phosphate. The latter compound then reacts with a oleoyl-CoA: lysophosphatidate acyltransferase resulting in the release of a phosphatidic acid. The latter compound reacts with Phosphatidic acid phosphohydrolase 1 resulting in the release of diacyl glycerol. This compound can be metabolized through a CTP-dependent diacylglycerol kinase 1 resulting in the release of a phosphatidic acid. Phosphatidylcholine is degraded by a phospholipase resulting in the release of choline and phosphatidic acid. Phosphatidylcholine can react with lysophospholipase resulting in the release of two fatty acids and a glycerophosphocholine. The latter compound reacts with a glycerophosphodiester phosphodiesterase resulting in the release of glycerol 3-phosphate and choline. Choline is phosphorylated through a choline kinase resulting in the release of phosphorycholine which can react with choline-phosphate cytidyltransferase resulting in the release of citicoline. The latter compound reacts with a diacylglycerol through a diacylglycerol cholinephosphotransferase resulting in the release of a phosphatidylcholine.
What is the definition of Inositol Phosphate Metabolism ?,"Inositol phosphates are a group of molecules that are important for a number of cellular functions, such as cell growth, apoptosis, cell migration, endocytosis, and cell differentiation. Inositol phsosphates consist of an inositol (a sixfold alcohol of cyclohexane) phosphorylated at one or more positions. There are a number of different inositol phosphates found in eukaryotes, distinguishable by the number and position of the phosphate groups. Inositol phosphate can be formed either as a product of phosphatidylinositol phosphate metabolism or from glucose 6-phosphate via the enzyme inositol-3-phosphate synthase 1. Conversion between the different types of inositol phosphates then occurs via a number of specific inositol phosphate kinases and phosphatases, which add (kinase) or remove (phosphatase) phosphate groups. The differing roles of the numerous inositol phosphates means that their metabolism must be tightly regulated. This is done via the localization and activation/deactivation of the various kinases and phosphatases, which can be found in the cytoplasm, nucleus or endoplasmic reticulum. The unphosphorylated inositol ring can be used to produce phosphoinositides through phosphatidylinositol phosphate metabolism."
What is the definition of Inositol Metabolism ?,"Inositol (also known as myo-inositol) is a carbocyclic polyol that can be found in many food such as nuts and beans. Inositol (e.g. inositol phosphates, etc.) can act as secondary messengers in eukaryotic cells. Inositol can be synthesized from three resources: inositol monophosphatase 1 can catalyze D-Myo-inositol 4-phosphate, myo-inositol 1-phosphate and 1D-myo-Inositol 3-phosphate to form inositol with water as cofactor. "
What is the definition of Lipoic Acid Metabolism?,"The lipoic acid metabolism involves the metabolism of octanoyl-acp by reacting with a sulfur donor and a S-adenosylmethionine through a lipoic acid synthetase resulting in the release of L-methionine, deoxyadenosine and lipoyl-ACP. Lipoyl-ACP reacts with an apoprotein through a through a lipoyl(octanoyl) transferase resulting in the release of an ACP and a protein N6-(lypoyl)lysine.Octanoyl-acp can also interact with a apoprotein through a lipoyl(octanoyl) transferase resulting in the release of an ACP and a protein N6-(octanoyl)lysine. Protein N6-(octanoyl) lysine reacts with  sulfur donor and a S-adenosylmethionine through a lipoic acid synthetase resulting in the release of L-methionine, deoxyadenosine and Protein N6(lipoyl) lysine."
What is the definition of N-Glycan Biosynthesis?,"The N-glycan biosynthesis is a pathway involving the creation of a dolichol, and the consecutive reactions involving the addition of Acetylglucosaminyl groups, mannosyl groups and glucosyl groups. The set of reactions all happen in the ER membrane. The resulting glucosyl3mannosyl9-N-acetylglucosaminyl2-diphosphodolichol is used as protein modificator."
What is the definition of Nitrogen Metabolism?,The metabolism of nitrogen in yeast involves ammonia and amino acids. Ammonia and oxoglutaric acid react with glutamate dehydrogenase resulting in the release of glutamic acid. Isocitric acid acid reacts with isocitrate dehydrogenase resulting in the release of Oxoglutaric acid which reacts with glutamine resulting in the release of glutamic acid.
What is the definition of Riboneogenesis?,"The riboneogenesis pathway is in charge of converting 3 carbon units into ribose. This pathway involves the conversion of fructose 6 phosphate which can be derived from the gluconeogenesis pathway. Fructose 6 phosphate reacts with a glyceraldehyde 3 phosphate through a transketolase resulting in the release of erythrose 4 phosphate and xylulose 5 phosphate. Erythrose 4 phosphate reacts with a dihydroxyacetone phosphate resulting in a release of sedoheptulose 1,7-biphosphate. Sedoheptulose 1,7-biphosphate is transformed by SHB17 resulting in the release of sedoheptulose 7 phosphate and a phosphate. Sedoheptulose 7 phosphate  reacts with a glyceraldehyde 3 phosphate through a transketolase resulting in the release of xylulose 5 phosphate and ribose 5 phosphate. Ribose 5 phosphate can react with reversibly through a ribose 5 phosphate ketol-isomerase resulting in the release of ribulose 5 phosphate. Xylulose 5 phosphate can react reversibly through a ribulose 5 phosphate 3-epimerase resulting in the release of ribulose 5 phosphate."
What is the definition of TOR Signalling Pathway: Rapamycin-Based Repression?,"The TOR signalling pathway is responsible for the cellular reactions towards nutrient and energy availability and hypoxia/stress. When TOR1/2 is activated, it activates TAP42 which in turn can inhibit SIT4 . I can also activate TAP41 phosphorylation. The enzyme SIT4 activates the dephosphorylation of TIP41 which in turn inhibits TAP42. The enzyme SIT4 also activates the dephosphorylation of Ure2-Gln3 complex and the separation of Ure2 and Gln3. Gln3 then gets incorporated into the nucleus resulting in the transcription of GLN1, GLT1,GDH1,GDH2,GAP1,MEP2,DAL3,PUT1 which are incorporated into Nitrogen Utilization"
What is the definition of Stress-Activated Signalling Pathways: Low Osmolarity?,"Stress-activated protein kinase pathways in Saccharomyces. The HOG1 MAPK pathway is controlled by two separate osmosensors, SLN1 and SHO1. Sln1 is activated in low osmolarity, thus repressing Ssk1 by phosphorylating it. Ssk1 is in charge of activating Ssk2/22 which in turn activates Pbs2 and in turn activates Hog1. SHO1 is activated during high osmolarity, resulting in Ste11 being activated, which in turn activates Pbs2 and activates Hog1.Ptp2 and Ptp3 negatively regulates Hog1."
What is the definition of Stress-Activated Signalling Pathways: High Osmolarity?,"Stress-activated protein kinase pathways in Saccharomyces. The HOG1 MAPK pathway is controlled by two separate osmosensors, SLN1 and SHO1. Sln1 is activated in low osmolarity, thus repressing Ssk1 by phosphorylating it. Ssk1 is in charge of activating Ssk2/22 which in turn activates Pbs2 and in turn activates Hog1. SHO1 is activated during high osmolarity, resulting in Ste11 being activated, which in turn activates Pbs2 and activates Hog1. Ptp2 and Ptp3 negatively regulates Hog1."
What is the definition of Gluconeogenesis from L-Malic Acid ?,"L-malic acid is metabolized through 3 possible ways: NAD driven malate dehydrogenase resulting in oxalacetic acid, NADP driven malate dehydrogenase B resulting pyruvic acid or malate dehydrogenase, NAD-requiring resulting in pyruvic acid. Oxalacetic acid is processed by phosphoenolpyruvate carboxykinase (ATP driven) while pyruvic acid is processed by phosphoenolpyruvate synthetase resulting in phosphoenolpyruvic acid. This compound is dehydrated by enolase resulting in an 2-phosphoglyceric acid. This compound is then isomerized by 2,3-bisphosphoglycerate-independent phosphoglycerate mutase resulting in a 3-phosphoglyceric acid which is phosphorylated by an ATP driven phosphoglycerate kinase resulting in an glyceric acid 1,3-biphosphate. This compound undergoes an NADH driven glyceraldehyde 3-phosphate dehydrogenase reaction resulting in a D-Glyceraldehyde 3-phosphate which is first isomerized into dihydroxyacetone phosphate through an triosephosphate isomerase. D-glyceraldehyde 3-phosphate and Dihydroxyacetone phosphate react through a fructose biphosphate aldolase protein complex resulting in a fructose 1,6-biphosphate. This compound is metabolized by a fructose-1,6-bisphosphatase resulting in a Beta-D-fructofuranose 6-phosphate which is then isomerized into a Beta-D-glucose 6-phosphate through a glucose-6-phosphate isomerase."
What is the definition of TCA Cycle ?,"The TCA cycle (tricarboxylic acid cycle) is also known as the citric acid cycle and the Krebs cycle. This pathway is the catabolism of aerobic respiration which produces energy and reducing power. It also initiates the production of precursors necessary for biosynthesis. If the carbon source for the cycle is acetate then citrate synthase becomes rate-limiting. Respiration produces ATP through a process of compounds acting as electron donors transferring electrons to electron acceptors. During this electron transport chain, a proton motive force is generated by the transport of protons outside the cytoplasmic membrane. As protons return to the cytoplasm, a multisubunit ATPase catalyzes the production of ATP from the proton motive force energy. During aerobic respiration, the final electron acceptor is oxygen. During anaerobic respiration, several organic compounds act as acceptors such as hydrogen, fumarate and nitrate. The cycle can start from Acetyl-CoA interacting with Oxalacetic acid and water through a citrate synthase monomer resulting in a hydrogen ion, CoA and a Citric Acid. The latter compound is dehydrated by a Citrate hydro-lyase resulting in the release of water and a cis-Aconitic acid. This compound is then hydrated through a Citrate hydro-lyase resulting in a D-threo-Isocitric acid. This compound is decarboxylated by an NADP dependent Citrate dehydrogenase, resulting in a release of carbon dioxide and NADPH and Oxoglutaric acid. The oxoglutaric acid interacts with a Coenzyme A through a NAD driven 2-oxoglutarate dehydrogenase resulting in a release of carbon dioxide, an NADH and succinyl-CoA. The succinyl-CoA interacts with a phosphate and an ADP through a 2-oxoglutarate dehydrogenase resulting in a CoA, an ATP and Succinic Acid. Succinic acid interacts with a ubiquinone, in this case a ubiquinone 1 through a succinate:quinone oxidoreductase resulting in an ubiquinol, in this case a ubiquinol-1 and a fumaric acid. The fumaric acid interacts with water through a fumarase hydratase resulting in a L-Malic acid. Malic acid can either react with a NAD dependent dehydrogenase resulting in the release of pyruvate. Malic Acid acid can also react with a malate dehydrogenase resulting in the release of oxalacetic acid"
What is the definition of Alanine Metabolism?,"The alanine biosynthesis starts with hypoxic conditions leading to large amounts of alanine being produced either through reactions in chloroplast, mitochondrion or cytoplasm Alanine concentration decreases after the plants return to normal oxygen conditions. Alanine production can be used by plants to conserve nitrogen and carbon atoms during anaerobic fermentation, otherwise, nitrogen and carbon atoms may be lost. Alanine is degraded and the nitrogen stored is released."
What is the definition of Arginine Metabolism?,"The metabolism of arginine begins like glutamic acid reacting with acetyl-CoA through a amino-acid acetyltransferase resulting in the release of coenzyme A, hydrogen ion and a N-acetyl-L-glutamate. The latter reacts with an ATP through acetylglutamate kinase resulting in the release of ADP  and  N-acetylglutamyl-phosphate.  The latter then reacts with an NADPH and a Hydrogen ion through a n-acetyl-gamma-glutamyl-phosphate reductase resulting in the release of phosphate, NADP and N-acetyl-L-glutamate 5-semialdehyde. The latter compound reacts with L-glutamate through an acetylornithine transaminase resulting in the release of oxoglutaric acid and N-acetyl-L-ornithine. The latter reacts with Water through a acetylornithine deacetylase resulting in the release of acetate and L-ornithine. Ornithine can also be produced by the acetyl cycle. The acetyl cycle starts with N-acetylglutamic acid being phosphorylated through an acetylglutamate kinase resulting in the release of ADP and N-acetylglutamyl-phosphate. The latter compound reacts with NADPH and a hydrogen ion through a N-acetyl-gamma-glutamyl-phosphate reductase  resulting in the release of  a phosphate, NADP and N-acetyl-L-glutamic 5-semialdehyde. The latter reacts with L-glutamate through an acetyl ornithine transaminase resulting in the release of oxoglutaric acid and N-acetylornithine. The latter compound reacts with L-glutamic acid resulting in the release of L-ornithine and N-acetylglutamate. The latter compound starts the cycle over again.Ornithine reacts with carbomoyl phosphate through an OTC resulting in the release of phosphate, hydrogen ion and L-citrulline. The latter compound reacts with ATP, and L-aspartate through a argininosuccinate synthase resulting in the release of AMP, diphosphate, hydrogen ion and L-arginino-succinate. The latter compound reacts with argininosuccinate lyase resulting in the release of fumarate and l-arginine.Arginine reacts with water through arginase resulting in the release of urea and l-ornithine. Ornithine reacts with oxoglutaric acid through an ornithine aminotransferase resulting in the release of glutamic acid and l-glutamate 5- semialdehyde which can spontaneously react to produce S-pyrroline-5-carboxylate. The latter reacts with pyrroline 5-carboxylate reductase resulting in the release of proline. Arginine  eacts with water through arginase resulting in the release of urea and l-ornithine. Ornithine reacts with oxoglutaric acid through an ornithine aminotransferase resulting in the release of glutamic acid and l-glutamate 5- semialdehyde  react with pyrroline 5 carboxylate dehydrogenase resulting in the release of glutamic acid."
What is the definition of Proline Metabolism?,"The metabolism of proline begins like glutamic acid reacting with acetyl-CoA through a amino-acid acetyltransferase resulting in the release of coenzyme A, hydrogen ion and a N-acetyl-L-glutamate. The latter reacts with an ATP through acetylglutamate kinase resulting in the release of ADP and N-acetylglutamyl-phosphate. The latter then reacts with an NADPH and a Hydrogen ion through a n-acetyl-gamma-glutamyl-phosphate reductase resulting in the release of phosphate, NADP and N-acetyl-L-glutamate 5-semialdehyde. The latter compound reacts with L-glutamate through an acetylornithine transaminase resulting in the release of oxoglutaric acid and N-acetyl-L-ornithine. The latter reacts with Water through a acetylornithine deacetylase resulting in the release of acetate and L-ornithine. Ornithine can also be produced by the acetyl cycle. The acetyl cycle starts with N-acetylglutamic acid being phosphorylated through an acetylglutamate kinase resulting in the release of ADP and N-acetylglutamyl-phosphate. The latter compound reacts with NADPH and a hydrogen ion through a N-acetyl-gamma-glutamyl-phosphate reductase resulting in the release of a phosphate, NADP and N-acetyl-L-glutamic 5-semialdehyde. The latter reacts with L-glutamate through an acetyl ornithine transaminase resulting in the release of oxoglutaric acid and N-acetylornithine. The latter compound reacts with L-glutamic acid resulting in the release of L-ornithine and N-acetylglutamate. The latter compound starts the cycle over again. Ornithine reacts with carbomoyl phosphate through an OTC resulting in the release of phosphate, hydrogen ion and L-citrulline. The latter compound reacts with ATP, and L-aspartate through a argininosuccinate synthase resulting in the release of AMP, diphosphate, hydrogen ion and L-arginino-succinate. The latter compound reacts with argininosuccinate lyase resulting in the release of fumarate and l-arginine. Arginine eacts with water through arginase resulting in the release of urea and l-ornithine. Ornithine reacts with oxoglutaric acid through an ornithine aminotransferase resulting in the release of glutamic acid and l-glutamate 5- semialdehyde react with pyrroline 5 carboxylate dehydrogenase resulting in the release of glutamic acid.Arginine reacts with water through arginase resulting in the release of urea and l-ornithine. Ornithine reacts with oxoglutaric acid through an ornithine aminotransferase resulting in the release of glutamic acid and l-glutamate 5- semialdehyde which can spontaneously react to produce S-pyrroline-5-carboxylate. The latter reacts with pyrroline 5-carboxylate reductase resulting in the release of proline. Proline is degraded by reacting with a proline dehydrogenase resulting in the release of S-1-pyrroline 5-carboxylate. The latter is then spontaneously reacts with water and hydrogen ion resulting in the release of L-glutamate-5-semialdehyde. The latter compoundreacts with NAD and water through a 1-pyrroline-5-carboxylate dehydrogenase resulting in the release of 2 hydrogen ions, NADH and L-glutamic acid."
What is the definition of Asparagine Metabolism?,"Asparagine is one of the twenty amino acids that combine to construct proteins according to the genetic code. In both eukaryotes and prokaryotes, L-asparagine is biosynthesized from L-aspartate via amidation using L-glutamine as an amino group donor. The first of the two reactions involved is catalyzed by asparagine synthetase [glutamine-hydrolyzing] 1. However, the second reaction is catalyzed by both asparagine synthetase [glutamine-hydrolyzing] 1 and 2. Asparagine synthetase 1 is negatively controlled by light and sucrose whereas asparagine synthetase 2 is positively controlled by light and sucrose. Asparagine gets metabolized back into L-aspartic acid by reacting with water through an L-asparaginase, resulting in the release of ammonium and L-aspartic acid."
What is the definition of Aspartate Metabolism?,"Aspartate is synthesized from oxaloacetic acid and l-glutamate in the cytosol, the chloroplast, the mitochondria and the peroxisome. Aspartate is broken down via conversion to malate, a part of the reversible malate-aspartate shuttle in the mitochondrial and cytoplasmic space. This shuttle involves the transfer of reduction equivalents across the mitochondrial membrane to produce ATP.  NADH is unable to cross the inner mitochondrial membrane. Therefore, the shuttle allows electrons from NADH in the cytosol, a product of glycolysis, to cross the inner mitochondrial membrane to produce ATP. "
What is the definition of Lysolipid Incorporation into Mitochondria?,"Lysolipids such as lysophosphatidylethanolamine, lysophosphatidylcholine, lysophosphatidylserine and lysophosphatidylinositol get transported into the cell through a phospholipid ATPase. Once in the cytosol they are incorporated into the mitochondria membrane through a Ale1p transport membrane where phosphatidylcholine is generated."
What is the definition of Lysolipid Incorporation into ER?,"Lysolipids such as lysophosphatidylethanolamine, lysophosphatidylcholine, lysophosphatidylserine and lysophosphatidylinositol get transported into the cell through a phospholipid ATPase. Once in the cytosol they are incorporated into the ER membrane through a Ale1p transport membrane where phosphatidylcholine is generated."
What is the definition of Glutamine Metabolism?,"Glutamine biosynthesis begins in the chloroplast with pyruvic acid reacting with an ATP and phosphate through an orthophosphate dikinase resulting in the release of diphosphate, AMP, a hydrogen ion and phosphoenolpyruvate. The latter compound reacts with hydrogen carbonate through a phosphoenolpyruvate carboxylase 3 resulting in the release of a phosphate and oxalacetic acid. Oxalacetic acid can be converted to citric acid either in the peroxisome or in the mitochondria. Citric acid reacts with an aconitate hydratase resulting in the release of cis-Aconitic acid in the mitchondria or in the cytosol. Cis-Aconitic acid reats with an aconitate hydratase again either in the mitochondria or a cytosol resulting in the release of isocitric acid. Isocitric acid reacts either with a NAD dependent isocitrate dehydrogenase or an NADP isocitrate dehydrogenase resulting in the release of oxoglutaric acid. Oxoglutaric acid reacts with a ferredoxin dependent glutamate synthase resulting in the release of a glutamic acid. glutamic acid reacts with a glutamine synthetase in the cytosol resulting in the release of L-glutamine.L-glutamine is degraded in the arginine metabolism  or react with a PDX2 resulting in the release of glutamic acid which can be then degraded in a glutamic acid metabolism pathway."
What is the definition of Glutamic Acid Metabolism?,"The metabolism of glutamic acid can start either in the chloroplast or in the mitochondria. This is done through a oxoglutaric acid reacting with a ferredoxin-dependent glutamic acid synthase resulting in the release of L-glutamic acid. Other reactions also involving oxoglutaric acid conversion to l-glutamic acid are: in the chloroplast: Oxoglutaric acid, glutamine , NADH and Hydrogen ion react through a glutamate synthase [NADH] resulting in the release of NAD and L-glutamic acid. in the mitochondria: Oxoglutaric acid, ammonium and NADPH react with a glutamate dehydrogenase 3 resulting in the release of NADP, water and L-glutamic acid.Oxoglutaric acid, ammonium and NADPH react with a glutamate dehydrogenase 1 & 2 resulting in the release of nNADP, water and L-glutamic acid.L-glutamic acid is degraded back to glutamine and oxoglutaric acid or it reacts with glutamate decarboxylase complex resulting in the release of gamma aminobutyric acid. The latter compound reacts with a either an oxoglutaric aci or a pyruvic acid through a Gamma-aminobutyrate transaminase POP2 resulting in the release of l-glutamic acid and succinic acid semialdehyde or l-alanine and succinic acid semialdehyde.. Succinic acid semialdehyde can react to a water molecule and NAD through a succinate-semialdehyde dehydrogenase resulting in the release of NADH, a hydrogen ion and succinic acid. Succinic acid semialdehyde can also react with a hydrogen ion and an NADPH through a glyoxylate/succinic semialdehyde reductase resulting in the release of NADP and 4-hydroxybutyric acid."
What is the definition of Histidine Metabolism?,"The biosynthesis of histidine begins with the transformation of D-ribose 5-phosphate through an ATP driven pyrophosphokinase resulting in the release of AMP, hydrogen ion and a phosphoribosyl pyrophosphate. The resulting compound then reacts with an ATP phosphoribosyltransferase resulting in the release of pyrophosphate and 1-(5-phosphoribosyl)-ATP. The latter compound then reacts with a histidine biosynthesis bifunctional protein resulting in the release of hydrogen ion, a pyrophosphate and phosphoribosyl-AMP. The resulting compound is then dehydrated through a histidine biosynthesis trifunctional protein resulting in the release of a phosphoribosylformiminoAICAR-phosphate. This compound then reacts with a 1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino] imidazole-4-carboxamide isomerase resulting in the release of a phosphoribulosylformimino-AICAR-P. This resulting compound then reacts with an L-glutamine through a imidazole glycerol phosphate synthase hisHF resulting in the release of glutamic acid, AICAR, hydrogen ion and D-Erythro-imidazoles glycerol phosphate. The latter compound reacts with a imidazoleglycerol-phosphate dehydratase results in the release of a water molecule and imidazole acetol-phosphate. The resulting compound reacts with L-glutamic acid through a histidinol-phosphate aminotransferase resulting in the release of oxoglutaric acid L-histidinol phosphate. Histidinol phosphate reacts with a water molecule through a histidinol-phosphatase resulting in the release of a phosphate and a histidinol. The resulting compound reacts with an NAD driven histidine biosynthesis trifunctional protein resulting in the release of histidinol. Histidinol reacts with water through a histidine biosynthesis trifunctional protein resulting in the release of L-histidine. Histidine is then degraded into histamine. "
What is the definition of Isoleucine Degradation?,"The degradation of isoleucine starts either in the mitochondria or the cytosol. L-isoleucine reacts with 2-oxoglutarate through a branch-chain amino acid aminotransferase resulting in the release of L-glutamate and 3-methyl-2-oxopentanoate. The latter compound reacts with 2-oxoisovalerate carboxy-lyase resulting in the release of carbon dioxide and methylbutanoyl. Methylbutanol reacts with oxidized flavoproteins resulting in the release of a reduced flavoprotein and tiglyl-CoA. The latter then reacts with water resulting in the release of 2-methyl-3-hydroxybutyryl-CoA. The latter compound reacts with NAD resulting in the release of NADH, hydrogen ion and 2-methylacetoacetyl-CoA. The latter then reacts with a Coenzyme A resulting in the release of propanoyl-CoA and acetyl-CoA. This degradation pathways may be an important detoxification mechanism to prevent the build up of branched chain aminoacids and their derived alpha-keto acids which are cytotoxic."
What is the definition of Leucine Degradation?,"The degradation of L-leucine starts either in the mitochondria, the cytosol or the chloroplast. L-leucine reacts with 2-oxoglutarate through a branch-chain amino acid aminotransferase resulting in the release of ketoleucine and glutamate. Ketoleucine reacts with coenzyme a through a NAD dependent branched chain keto-acid dehydrogenase complex resulting in the release of NADH, carbon dioxide and isovaleryl-CoA. Isovaleryl-CoA reacts with an oxidized electron flavoprotein resulting in the release of a reduced flavoprotein and a methylcrotonyl-CoA. The latter reacts with ATP and hydrogen carbonate through a 3-methylcrotonyl-CoA carboxylase resulting in the release of phosphate, ADP, hydrogen ion and 3-methylglutaconyl-CoA. The latter compound reacts with water through a methylglutaconyl-CoA hydratase resulting in the release of hydroxy-3-methylglutaryl-CoA. The latter reacts with a hydroxymethylglutaryl-CoA lyase resulting in the release of acetyl-CoA and acetoacetate."
What is the definition of Cholesterol Biosynthesis and Metabolism CE(14:0)?,"The biosynthesis of Cholesterol starts with acetyl-CoA reacts with acetyl-CoA c-acetyltransferase resulting in the release of CoA acetoacetyl-CoA, The latter compound then reacts with an acetyl-coa through a hydroxymethylglutaryl-CoA synthase resulting in the release of 3-hydroxy-3-methylglutaryl-CoA. The latter compound in turn reacts with a NADPH through a 3-hydroxy-3-methylglutaryl-coenzyme A reductase resulting in the release of a NADP, Coenzyme A and Mevalonic acid. The latter is then phosphorylated by ATP through a mevalonate kinase resulting in the release of ADP and Mevalonic acid-5P which is then phosphorylated by ATP through a phosphomevalonate kinase resulting in the release of ADP and (S)-5-diphosphomevalonic acid. The latter compound in turn reacts with ATP through a diphosphomevalonic decarboxylase resulting in the release of phosphate, ADP, carbon dioxide and Isopentenyl pyrophosphate. The latter compound in turn reacts with isopentenyl diphosphate delta isomerase resulting in the release of dimethylallylpyrophosphate. The latter compound then reacts with isopentenyl pyrophosphate through a farnesyl pyrophosphate synthase resulting in the release of Geranyl-PP. The latter then reacts with an isopentenyl pyrophosphate through farnesyl pyrophosphate synthase resulting in the release of pyrophospate and farnesyl pyrophosphate. Farnesyl pyrophosphate then reacts with NADPH through a squalene synthase in order to produce squalene while also releasing two phosphates and NADP. Squalene then reacts with oxygen and NADPH through a squalene monooxygenase resulting in the release of water, NADP and (S)-2,3-epoxysqualene. The latter in turn reacts with lanosterol synthase resulting in the release of lanosterin. Lanosterin then reacts with oxygen and NADPH through a lanosterol 14-alpha demethylase resulting in the release of formic acid, water, NADP and 4,4-dimethylcholesta-8,14,24-trienol. The latter compound in turn is reduced by an NADPH through a Delta (14)-sterol reductase resulting in the release of NADP and 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. The latter reacts with hydrogen ion,oxygen and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-hydroxymethyl-4B-methyl-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with a hydrogen ion, water, and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen, NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4B-methyl-4a-carboxy-cholesta-8,24-dien-3B-ol. The latter reacts with an NADP through c-3 sterol dehydrogenase resulting in the release of NADPH, carbon dioxide and 3-keto-4-methylzymosterol. The latter is reduced by NADPH through a 3-keto sterol reductase resulting in the release of NADP and 4a-methylzymosterol. The latter then reacts with hydrogen, oxygen and nadph through methylsterol monooxygenase resulting in the release of water, NADP and 4a-hydroxymethyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with water, hydrogen and NADPH through a methylsterol monooxygenase resulting in the release of water, NADP and 4a-formyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen and NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4a-carboxy-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with NADP through a C-3 sterol dehydrogenase resulting in the release of carbon dioxide, NADPH and 5a-cholesta-8,24-dien-3-one. The latter reacts with hydrogen ion and NADPH through a 3-keto sterol reductase resulting in the release of NADP and zymosterol. Zymosterol can either be used to create ergosterol starts with zymosterol reacting with S-adenosylmethionine through a sterol 24-c-methyltransferase resulting in the release of S-adenosylhomocysteine, hydrogen ion and fecosterol. Fecosterol reacts with C-8 sterol isomerase resulting in the release of episterol. Episterol reacts with oxygen, hydrogen ion and ferrocytochrome c through a C-5 sterol desaturase resulting in the release of ferricytochrome c, water and 5,7,24(28)-ergostatrienol. The latter reacts with hydrogen ion, oxygen, NADPH and c-22 sterol desaturase resulting in the release of water, NADP AND ERGOSTA-5,7,22,24(28)-tetraen-3-B-ol. The latter compound reacts with hydrogen ion and NADPH through a C-24 sterol reductase resulting in the release of NADP and ergosterol. Zymosterol reacts with C-8 sterol isomerase resulting in the release of 5a-cholesta-7,24-dien-3b-ol. The latter compound reacts with C-5 sterol desaturase resulting in the release of 7-dehydrodesmosterol. The latter is then converted spontaneously through desmosterol. Desmosterol is then spontaneously turned into cholesterol which can in turn react with tetradecanoyl-CoA spontaneously resulting in the release of Coenzyme A and CE(14:0)."
What is the definition of Cholesterol Biosynthesis and Metabolism CE(10:0)?,"The biosynthesis of Cholesterol starts with acetyl-CoA reacts with acetyl-CoA c-acetyltransferase resulting in the release of CoA acetoacetyl-CoA, The latter compound then reacts with an acetyl-coa through a hydroxymethylglutaryl-CoA synthase resulting in the release of 3-hydroxy-3-methylglutaryl-CoA. The latter compound in turn reacts with a NADPH through a 3-hydroxy-3-methylglutaryl-coenzyme A reductase resulting in the release of a NADP, Coenzyme A and Mevalonic acid. The latter is then phosphorylated  by ATP through a mevalonate kinase resulting in the release of ADP and Mevalonic acid-5P which is then phosphorylated by ATP through a phosphomevalonate kinase resulting in the release of ADP and (S)-5-diphosphomevalonic acid. The latter compound in turn reacts with ATP through a diphosphomevalonic decarboxylase resulting in the release of phosphate, ADP, carbon dioxide and Isopentenyl pyrophosphate. The latter compound in turn reacts with isopentenyl diphosphate delta isomerase resulting in the release of dimethylallylpyrophosphate. The latter compound then reacts with isopentenyl pyrophosphate through a farnesyl pyrophosphate synthase resulting in the release of Geranyl-PP. The latter then reacts with an isopentenyl pyrophosphate through farnesyl pyrophosphate synthase resulting in the release of pyrophospate and farnesyl pyrophosphate. Farnesyl pyrophosphate then reacts with NADPH through a squalene synthase in order to produce squalene while  also releasing two phosphates and NADP. Squalene then reacts with oxygen and NADPH through a squalene monooxygenase resulting in the release of water, NADP and (S)-2,3-epoxysqualene. The latter in turn reacts with lanosterol synthase resulting in the release of lanosterin. Lanosterin then reacts with oxygen and NADPH through a lanosterol 14-alpha demethylase resulting in the release of formic acid, water, NADP and 4,4-dimethylcholesta-8,14,24-trienol. The latter compound in turn is reduced by an NADPH through a Delta (14)-sterol reductase resulting in the release of NADP and 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. The latter reacts with hydrogen ion,oxygen and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-hydroxymethyl-4B-methyl-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with a hydrogen ion, water, and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen, NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4B-methyl-4a-carboxy-cholesta-8,24-dien-3B-ol. The latter reacts with an NADP through c-3 sterol dehydrogenase resulting in the release of NADPH, carbon dioxide and 3-keto-4-methylzymosterol.  The latter is reduced by NADPH through a 3-keto sterol reductase resulting in the release of NADP and 4a-methylzymosterol. The latter then reacts with hydrogen, oxygen and nadph through methylsterol monooxygenase resulting in the release of water, NADP and 4a-hydroxymethyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with water, hydrogen and NADPH through a methylsterol monooxygenase resulting in the release of water, NADP and 4a-formyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen and NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4a-carboxy-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with NADP through a C-3 sterol dehydrogenase resulting in the release of carbon dioxide, NADPH and 5a-cholesta-8,24-dien-3-one. The latter reacts with hydrogen ion and NADPH through a 3-keto sterol reductase resulting in the release of NADP and zymosterol. Zymosterol can either be used to create ergosterol starts with zymosterol reacting with S-adenosylmethionine through a sterol 24-c-methyltransferase resulting in the release of S-adenosylhomocysteine, hydrogen ion and fecosterol. Fecosterol reacts with C-8 sterol isomerase resulting in the release of episterol. Episterol reacts with oxygen, hydrogen ion and ferrocytochrome c through a C-5 sterol desaturase resulting in the release of ferricytochrome c, water and 5,7,24(28)-ergostatrienol. The latter reacts with hydrogen ion, oxygen, NADPH and c-22 sterol desaturase resulting in the release of water, NADP AND ERGOSTA-5,7,22,24(28)-tetraen-3-B-ol. The latter compound reacts with hydrogen ion and NADPH through a C-24 sterol reductase resulting in the release of NADP and ergosterol.Zymosterol reacts with C-8 sterol isomerase resulting in the release of 5a-cholesta-7,24-dien-3b-ol. The latter compound reacts with C-5 sterol desaturase resulting in the release of 7-dehydrodesmosterol. The latter is then converted spontaneously through desmosterol. Desmosterol is then spontaneously turned into cholesterol which can in turn react with Decanoyl-CoA spontaneously resulting in the release of Coenzyme A and CE(10:0)."
What is the definition of Cholesterol Biosynthesis and Metabolism CE(12:0)?,"The biosynthesis of Cholesterol starts with acetyl-CoA reacts with acetyl-CoA c-acetyltransferase resulting in the release of CoA acetoacetyl-CoA, The latter compound then reacts with an acetyl-coa through a hydroxymethylglutaryl-CoA synthase resulting in the release of 3-hydroxy-3-methylglutaryl-CoA. The latter compound in turn reacts with a NADPH through a 3-hydroxy-3-methylglutaryl-coenzyme A reductase resulting in the release of a NADP, Coenzyme A and Mevalonic acid. The latter is then phosphorylated by ATP through a mevalonate kinase resulting in the release of ADP and Mevalonic acid-5P which is then phosphorylated by ATP through a phosphomevalonate kinase resulting in the release of ADP and (S)-5-diphosphomevalonic acid. The latter compound in turn reacts with ATP through a diphosphomevalonic decarboxylase resulting in the release of phosphate, ADP, carbon dioxide and Isopentenyl pyrophosphate. The latter compound in turn reacts with isopentenyl diphosphate delta isomerase resulting in the release of dimethylallylpyrophosphate. The latter compound then reacts with isopentenyl pyrophosphate through a farnesyl pyrophosphate synthase resulting in the release of Geranyl-PP. The latter then reacts with an isopentenyl pyrophosphate through farnesyl pyrophosphate synthase resulting in the release of pyrophospate and farnesyl pyrophosphate. Farnesyl pyrophosphate then reacts with NADPH through a squalene synthase in order to produce squalene while also releasing two phosphates and NADP. Squalene then reacts with oxygen and NADPH through a squalene monooxygenase resulting in the release of water, NADP and (S)-2,3-epoxysqualene. The latter in turn reacts with lanosterol synthase resulting in the release of lanosterin. Lanosterin then reacts with oxygen and NADPH through a lanosterol 14-alpha demethylase resulting in the release of formic acid, water, NADP and 4,4-dimethylcholesta-8,14,24-trienol. The latter compound in turn is reduced by an NADPH through a Delta (14)-sterol reductase resulting in the release of NADP and 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. The latter reacts with hydrogen ion,oxygen and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-hydroxymethyl-4B-methyl-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with a hydrogen ion, water, and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen, NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4B-methyl-4a-carboxy-cholesta-8,24-dien-3B-ol. The latter reacts with an NADP through c-3 sterol dehydrogenase resulting in the release of NADPH, carbon dioxide and 3-keto-4-methylzymosterol. The latter is reduced by NADPH through a 3-keto sterol reductase resulting in the release of NADP and 4a-methylzymosterol. The latter then reacts with hydrogen, oxygen and nadph through methylsterol monooxygenase resulting in the release of water, NADP and 4a-hydroxymethyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with water, hydrogen and NADPH through a methylsterol monooxygenase resulting in the release of water, NADP and 4a-formyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen and NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4a-carboxy-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with NADP through a C-3 sterol dehydrogenase resulting in the release of carbon dioxide, NADPH and 5a-cholesta-8,24-dien-3-one. The latter reacts with hydrogen ion and NADPH through a 3-keto sterol reductase resulting in the release of NADP and zymosterol. Zymosterol can either be used to create ergosterol starts with zymosterol reacting with S-adenosylmethionine through a sterol 24-c-methyltransferase resulting in the release of S-adenosylhomocysteine, hydrogen ion and fecosterol. Fecosterol reacts with C-8 sterol isomerase resulting in the release of episterol. Episterol reacts with oxygen, hydrogen ion and ferrocytochrome c through a C-5 sterol desaturase resulting in the release of ferricytochrome c, water and 5,7,24(28)-ergostatrienol. The latter reacts with hydrogen ion, oxygen, NADPH and c-22 sterol desaturase resulting in the release of water, NADP AND ERGOSTA-5,7,22,24(28)-tetraen-3-B-ol. The latter compound reacts with hydrogen ion and NADPH through a C-24 sterol reductase resulting in the release of NADP and ergosterol. Zymosterol reacts with C-8 sterol isomerase resulting in the release of 5a-cholesta-7,24-dien-3b-ol. The latter compound reacts with C-5 sterol desaturase resulting in the release of 7-dehydrodesmosterol. The latter is then converted spontaneously through desmosterol. Desmosterol is then spontaneously turned into cholesterol which can in turn react with Dodecanoic acid spontaneously resulting in the release of Coenzyme A and CE(12:0)."
What is the definition of Methionine Metabolism?,"The methionine metabolism starts from aspartate-produced homoserine. Homoserine reacts with HSK resulting in the release of O-phospho-L-homoserine. The latter compound interacts with cysteine through CGS resulting in the release of phosphate and cystathionine. The latter compound reacts with COI3 resulting in the release of 2-aminoprop-2-enoate, hydrogen ion and homocysteine. Homocysteine can react with S-adenosyl-L-methionine through a HMT protein complex resulting in the release of methionine. Methionine can be used to generate S-adenosyl-L-methionine or it can generate oxobutanoate"
What is the definition of Cholesterol Biosynthesis and Metabolism CE(16:0)?,"The biosynthesis of Cholesterol starts with acetyl-CoA reacts with acetyl-CoA c-acetyltransferase resulting in the release of CoA acetoacetyl-CoA, The latter compound then reacts with an acetyl-coa through a hydroxymethylglutaryl-CoA synthase resulting in the release of 3-hydroxy-3-methylglutaryl-CoA. The latter compound in turn reacts with a NADPH through a 3-hydroxy-3-methylglutaryl-coenzyme A reductase resulting in the release of a NADP, Coenzyme A and Mevalonic acid. The latter is then phosphorylated by ATP through a mevalonate kinase resulting in the release of ADP and Mevalonic acid-5P which is then phosphorylated by ATP through a phosphomevalonate kinase resulting in the release of ADP and (S)-5-diphosphomevalonic acid. The latter compound in turn reacts with ATP through a diphosphomevalonic decarboxylase resulting in the release of phosphate, ADP, carbon dioxide and Isopentenyl pyrophosphate. The latter compound in turn reacts with isopentenyl diphosphate delta isomerase resulting in the release of dimethylallylpyrophosphate. The latter compound then reacts with isopentenyl pyrophosphate through a farnesyl pyrophosphate synthase resulting in the release of Geranyl-PP. The latter then reacts with an isopentenyl pyrophosphate through farnesyl pyrophosphate synthase resulting in the release of pyrophospate and farnesyl pyrophosphate. Farnesyl pyrophosphate then reacts with NADPH through a squalene synthase in order to produce squalene while also releasing two phosphates and NADP. Squalene then reacts with oxygen and NADPH through a squalene monooxygenase resulting in the release of water, NADP and (S)-2,3-epoxysqualene. The latter in turn reacts with lanosterol synthase resulting in the release of lanosterin. Lanosterin then reacts with oxygen and NADPH through a lanosterol 14-alpha demethylase resulting in the release of formic acid, water, NADP and 4,4-dimethylcholesta-8,14,24-trienol. The latter compound in turn is reduced by an NADPH through a Delta (14)-sterol reductase resulting in the release of NADP and 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. The latter reacts with hydrogen ion,oxygen and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-hydroxymethyl-4B-methyl-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with a hydrogen ion, water, and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen, NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4B-methyl-4a-carboxy-cholesta-8,24-dien-3B-ol. The latter reacts with an NADP through c-3 sterol dehydrogenase resulting in the release of NADPH, carbon dioxide and 3-keto-4-methylzymosterol. The latter is reduced by NADPH through a 3-keto sterol reductase resulting in the release of NADP and 4a-methylzymosterol. The latter then reacts with hydrogen, oxygen and nadph through methylsterol monooxygenase resulting in the release of water, NADP and 4a-hydroxymethyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with water, hydrogen and NADPH through a methylsterol monooxygenase resulting in the release of water, NADP and 4a-formyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen and NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4a-carboxy-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with NADP through a C-3 sterol dehydrogenase resulting in the release of carbon dioxide, NADPH and 5a-cholesta-8,24-dien-3-one. The latter reacts with hydrogen ion and NADPH through a 3-keto sterol reductase resulting in the release of NADP and zymosterol. Zymosterol can either be used to create ergosterol starts with zymosterol reacting with S-adenosylmethionine through a sterol 24-c-methyltransferase resulting in the release of S-adenosylhomocysteine, hydrogen ion and fecosterol. Fecosterol reacts with C-8 sterol isomerase resulting in the release of episterol. Episterol reacts with oxygen, hydrogen ion and ferrocytochrome c through a C-5 sterol desaturase resulting in the release of ferricytochrome c, water and 5,7,24(28)-ergostatrienol. The latter reacts with hydrogen ion, oxygen, NADPH and c-22 sterol desaturase resulting in the release of water, NADP AND ERGOSTA-5,7,22,24(28)-tetraen-3-B-ol. The latter compound reacts with hydrogen ion and NADPH through a C-24 sterol reductase resulting in the release of NADP and ergosterol. Zymosterol reacts with C-8 sterol isomerase resulting in the release of 5a-cholesta-7,24-dien-3b-ol. The latter compound reacts with C-5 sterol desaturase resulting in the release of 7-dehydrodesmosterol. The latter is then converted spontaneously through desmosterol. Desmosterol is then spontaneously turned into cholesterol which can in turn react with hexanoyl-CoA spontaneously resulting in the release of Coenzyme A and CE(16:0)."
What is the definition of Cholesterol Biosynthesis and Metabolism CE(18:0)?,"The biosynthesis of Cholesterol starts with acetyl-CoA reacts with acetyl-CoA c-acetyltransferase resulting in the release of CoA acetoacetyl-CoA, The latter compound then reacts with an acetyl-coa through a hydroxymethylglutaryl-CoA synthase resulting in the release of 3-hydroxy-3-methylglutaryl-CoA. The latter compound in turn reacts with a NADPH through a 3-hydroxy-3-methylglutaryl-coenzyme A reductase resulting in the release of a NADP, Coenzyme A and Mevalonic acid. The latter is then phosphorylated by ATP through a mevalonate kinase resulting in the release of ADP and Mevalonic acid-5P which is then phosphorylated by ATP through a phosphomevalonate kinase resulting in the release of ADP and (S)-5-diphosphomevalonic acid. The latter compound in turn reacts with ATP through a diphosphomevalonic decarboxylase resulting in the release of phosphate, ADP, carbon dioxide and Isopentenyl pyrophosphate. The latter compound in turn reacts with isopentenyl diphosphate delta isomerase resulting in the release of dimethylallylpyrophosphate. The latter compound then reacts with isopentenyl pyrophosphate through a farnesyl pyrophosphate synthase resulting in the release of Geranyl-PP. The latter then reacts with an isopentenyl pyrophosphate through farnesyl pyrophosphate synthase resulting in the release of pyrophospate and farnesyl pyrophosphate. Farnesyl pyrophosphate then reacts with NADPH through a squalene synthase in order to produce squalene while also releasing two phosphates and NADP. Squalene then reacts with oxygen and NADPH through a squalene monooxygenase resulting in the release of water, NADP and (S)-2,3-epoxysqualene. The latter in turn reacts with lanosterol synthase resulting in the release of lanosterin. Lanosterin then reacts with oxygen and NADPH through a lanosterol 14-alpha demethylase resulting in the release of formic acid, water, NADP and 4,4-dimethylcholesta-8,14,24-trienol. The latter compound in turn is reduced by an NADPH through a Delta (14)-sterol reductase resulting in the release of NADP and 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. The latter reacts with hydrogen ion,oxygen and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-hydroxymethyl-4B-methyl-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with a hydrogen ion, water, and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen, NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4B-methyl-4a-carboxy-cholesta-8,24-dien-3B-ol. The latter reacts with an NADP through c-3 sterol dehydrogenase resulting in the release of NADPH, carbon dioxide and 3-keto-4-methylzymosterol. The latter is reduced by NADPH through a 3-keto sterol reductase resulting in the release of NADP and 4a-methylzymosterol. The latter then reacts with hydrogen, oxygen and nadph through methylsterol monooxygenase resulting in the release of water, NADP and 4a-hydroxymethyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with water, hydrogen and NADPH through a methylsterol monooxygenase resulting in the release of water, NADP and 4a-formyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen and NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4a-carboxy-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with NADP through a C-3 sterol dehydrogenase resulting in the release of carbon dioxide, NADPH and 5a-cholesta-8,24-dien-3-one. The latter reacts with hydrogen ion and NADPH through a 3-keto sterol reductase resulting in the release of NADP and zymosterol. Zymosterol can either be used to create ergosterol starts with zymosterol reacting with S-adenosylmethionine through a sterol 24-c-methyltransferase resulting in the release of S-adenosylhomocysteine, hydrogen ion and fecosterol. Fecosterol reacts with C-8 sterol isomerase resulting in the release of episterol. Episterol reacts with oxygen, hydrogen ion and ferrocytochrome c through a C-5 sterol desaturase resulting in the release of ferricytochrome c, water and 5,7,24(28)-ergostatrienol. The latter reacts with hydrogen ion, oxygen, NADPH and c-22 sterol desaturase resulting in the release of water, NADP AND ERGOSTA-5,7,22,24(28)-tetraen-3-B-ol. The latter compound reacts with hydrogen ion and NADPH through a C-24 sterol reductase resulting in the release of NADP and ergosterol. Zymosterol reacts with C-8 sterol isomerase resulting in the release of 5a-cholesta-7,24-dien-3b-ol. The latter compound reacts with C-5 sterol desaturase resulting in the release of 7-dehydrodesmosterol. The latter is then converted spontaneously through desmosterol. Desmosterol is then spontaneously turned into cholesterol which can in turn react with stearidonoyl-CoA spontaneously resulting in the release of Coenzyme A and CE(18:0)."
What is the definition of Phenylalanine Metabolism?,Phenylalanine metabolism starts with chorismate reacting with chorismate mutase resulting in the release of prephenate. Prephenate can be converted into L-arogenate or 2-oxo-3-phenylpropanoic acid. Arogenate interacts with an arogenate dehydratase complex resulting in the release of phenylalanine. 2-oxo-3-phenylpropanoic acid reacts either with a pyruvate aminotransferase or with a TAT2 resulting in the release of phenylalanine. Phenylalanine reacts with an aminotransferase or a tryptophan pyruvate aminotransferase resulting in the release of 2-oxo-3-phenylpropanoic acid. The latter compound reacts with pyruvate decarboxylase resulting in the release of phenylacetaldehyde which then reacts spontaneously resulting in the release of 2-phenylethanol
What is the definition of Serine Metabolism?,"The biosynthesis of serine begins in the chloroplast with 3-phospho-D-glycerate being metabolize into 3-phosphohydroxypyruvate through a 3-phosphoglycerate dehydrogenase. The resulting compound 3-phosphohydroxypyruvate is transaminated into 3-phospho-L-serine through a phosphoserine transaminase. This is followed by 3-phospho-L-serine being dephosphorylated through a phosphoserine phosphatase resulting in the release of a phosphate and Serine.  Serine can also be incorporated into the mitochondrion and then serine  can then be used to synthesize glycine through a mitochondrial serine hydroxymethyltransferase. Glycine is then used to synthesize formic acid by first being metabolized into  5,10 methylene THF, which is transformed into a 5,10 methenyltetrahydrofolate , followed by an N10 formyl tetrahydrofolate and lastly formic acid, all through a mitochondrial C1-tetrahydrofolate synthase.It can also be used in tryptophan biosynthesis, glycine biosynthesis and cysteine biosynthesis"
What is the definition of Triacylglycerol Metabolism?,"The biosynthesis of triacylglycerol starts with glycerol 3-phosphate reacting with acyl-CoA through a glycerol-3-phosphate O-acyltransferase resulting in the release of LPA. This in turn reacts with an acyl-CoA through a lipase complex resulting in the release of CoA and phosphatidic acid. Phosphatidic acid reacts with water through a phosphatidic acid phosphohydrolase 1 resulting in the release of a phosphate and a diacylglycerol. This can be either turned back into a phosphatidic acid through a CTP-dependent diacylglycerol kinase. The diacylglycerol reacts in the endoplasmic reticulum with a acyl-coa through a diacylglycerol O-acyltransferase resulting in the release of Coenzyme A and a triacylglycerol. In the endoplasmic reticulum, diacylglycerol can also react with a monoacylglycerol resulting in the release of triacylglycerol. In the mitochondria, diacylglycerol reacts with a phosphocholine through a lysophosphatidylcholine acyltransferase resulting in the release of lysoPC and Triacylglycerol.The triacylglycerol is metabolized reacts with water through lipase resulting in the release of a fatty acid, hydrogen ion, and a diacylglycerol. Diacylglycerol reacts with a lipase 3 resulting in the release of a fatty acid and a monoacylglycerol. Monoacylglycerol reacts with monoglyceride lipase resulting in the release of a fatty acid in glycerol."
What is the definition of Phosphatidylcholine Biosynthesis?,"Phosphatidyl ethanolamine reacts with S-adenosylmethionine through a phosphatdylethanolamine N-methyltransferase resulting in the release of hydrogen ion and S-adenosylhomocysteine an a PE-NMe. The PE-NMe reacts with S'-adenosylmethionine through a phosphotidyl-N-methylethanolamine N-methyltransferase resulting in the release of hydrogen ion, s-adenosylhomocysteine and PE-NMe2. The PE-NMe2 reacts with s-adenosylmethionine through a phosphotidyl-N-methylethanolamine N-methyltransferase resuilting in the release of hydrogen ion, s-adenosylhomocysteine and PC"
What is the definition of Arginine and Proline Metabolism?,"Arginine and proline metabolism demonstrates the co-metabolism of arginine, ornithine, proline, citrulline and glutamate in mitochondria. Argininosuccinate synthase catalyzes citrulline into argininosuccinic acid with ATP and L-Aspartic acid. Argininosuccinic acid is cleaved by argininosuccinate lyase to generate L-arginine (arginine), which also generated fumaric acid for citric acid cycle. Citrulline can be generated from ornithine by the ornithine carbamoyltransferase at mitochondria; and ornithine can be generated by series of metabolism that is associated with proline dehydrogenase 1 (with cofactor FAD) and pyrroline-5-carboxylate reductase 2 at mitochondria. Proline is derived from L-glutamatic acid with conversion of L-glutamatic acid to 1-pyrroline-5-carboxylic acid by delta-1-pyrroline-5-carboxylate dehydrogenase and NAD; then 1-pyrroline-5-carboxylic acid can converted to L-proline via proline dehydrogenase 1 with cofactor FAD."
What is the definition of Shikimate Pathway (Chorismate Biosynthesis)?,"The shikimate pathway is composed of seven enzymatic reactions in the chloroplast by which phosphoenolpyruvate (PEP) and D-erythrose 4-phosphate (E4P) are converted to chorismate, the common precursor of the aromatic amino acids phenylalanine, tyrosine, and tryptophan as well as other metabolites (e.g. folates).  The pathway's absence in animals makes it an attractive target for new antimicrobial agents, anti-parasitic agents, and herbicides.  PEP can enter this pathway either from plastidic glycolysis or cytosolic glycolysis.  If it enters from the cytosol, then  it is pumped into the chloroplast by PEP/phosphate translocator (PPT), an antiporter that exports phosphate into the cytosol simultaneously.  Firstly, DAHP synthase, with the help of reduced thioredoxin (TRX) and a divalent cation (e.g. manganese) as cofactors, converts PEP, E4P, and water to 3-deoxy-D-arabino-heptulosonic acid 7-phosphate (DAHP) and phosphate.  Secondly, 3-dehydroquinate synthase eliminates a phosphate from DAHP resulting in 3-dehydroquinate. This enzyme requires NAD+ and a divalent cation (e.g. cobalt) as cofactors.  The next two reactions are catalyzed by the bifunctional enzyme 3-dehydroquinate dehydratase-shikimate dehydrogenase (DHQ-SDH).  In the pathway's third reaction, the enzyme's DHQ domain dehydrates 3-dehydroquinate to 3-dehydroshikimate.  In the fourth reaction, the enzyme's SDH domain uses NADPH to reversibly reduce 3-dehydroshikimate to shikimate, releasing NADP in the process.  Fifthly, shikimate kinase, which requires a divalent cation (e.g. manganese) as a cofactor, catalyzes the ATP-dependent phosphorylation of shikimate to shikimate 3-phosphate.  Sixthly, 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase converts shikimate-3-phosphate and PEP to EPSP, releasing a phosphate in the process.  Seventhly, chorismate synthase (CS) catalyzes the 1,4-trans elimination of the phosphate group from EPSP to form chorismate.  This enzyme requires reduced flavin mononucleotide (FMNH2) as a cofactor."
What is the definition of Pterin Biosynthesis (Folate Precursor)?,"Pterin biosynthesis is a pathway located in the cytosol by which GTP becomes hydroxymethyldihydropterin (HMDHP), the pterin precursor of folate biosynthesis.  Firstly, GTP cyclohydrolase (GCH) catalyzes the conversion of GTP and water to dihydroneopterin triphosphate, formic acid, and water.  Secondly, nudix hydrolase from the Nudix (NUcleotide DIphosphates linked to some moiety X) protein family of phosphohydrolases uses water to eliminate a pyrophosphate from dihydroneopterin phosphate and releases a hydrogen ion in the process. However, this enzyme is non-specific for this reaction, and therefore the true dihydroneopterin triphosphate diphosphatase may yet to be found.  Thirdly, dihydroneopterin phosphate phosphatase (Pase) dephosphorylates dihydroneopterin phosphate to 7,8-dihydroneopterin.  This enzyme has not yet been identified in any organism, but it is possible that reaction is carried out by a nonspecific phosphatase.  The fourth reaction is catalyzed by the enzyme dihydroneopterin aldolase (DHNA) whereby 7,8-dihydroneopterin is cleaved to form HMDHP and glycolaldehyde is released.  The second function of DHNA is epimerizing 7,8-dihydroneopterin to form 7,8-dihydromonapterin.  DHNA can also use 7,8-dihydromonapterin as a substrate to form HMDHP.  HMDHP has two fates.  It can either be pumped into the mitochondria by a yet to be discovered HMDHP transporter for use in folate biosynthesis, or be acted upon by cytosolic hydroxymethyldihydropterin pyrophosphokinase-dihydropteroate synthase (HPPK-DHPS).  HPPK-DHPS is a bifunctional enzyme that requires magnesium as a cofactor and catalyzes consecutive steps in the pterin and folate biosynthesis pathways. The HPPK domain uses ATP to diphosphorylate HMDHP to HMDHP pyrophosphate, releasing AMP and a hydrogen ion in the process. The DHPS domain incorporates pABA, diffused out from the chloroplast, to form dihydropteroate and a diphosphate."
What is the definition of Folate Biosynthesis?,"Folate biosynthesis is a pathway by which pterin and pABA precursors form tetrahydrofolate, an essential cofactor that takes part in various enzymatic reactions as a carrier for one-carbon units.  Although tetrahydrofolate is synthesized in the mitochondrial matrix, the pterin and pABA branches occur in the cytosol and the chloroplast, respectively.  The first reaction in the pABA branch is catalyzed by aminodeoxychorismate synthase (ADCS) whereby chorismate and L-glutamine is converted to aminodeoxychorismate and L-glutamic acid.  The second reaction in the pABA branch is catalyzed by aminodeoxychorismate lyase (ADCL) whereby aminodeoxychorismate is converted to pABA, pyruvic acid, and a hydrogen ion.  pABA then diffuses out of the chloroplast and into the mitochondrial matrix to be used in folate biosynthesis.  From the pterin branch,  hydroxymethyldihydropterin (HMDHP) is pumped into the mitochondria by a yet to be discovered HMDHP transporter.  The bifunctional enzyme hydroxymethyldihydropterin pyrophosphokinase-dihydropteroate synthase (HPPK-DHPS), which requires magnesium as a cofactor, catalyzes consecutive steps that unites the pABA and pterin branches. The HPPK domain uses ATP to diphosphorylate HMDHP to HMDHP pyrophosphate, releasing AMP and a hydrogen ion in the process. The DHPS domain incorporates pABA, diffused out from the chloroplast, to form dihydropteroate and a diphosphate.  Next, dihydrofolate (DHF) synthase catalyzes the ATP hydrolysis powered conversion of dihydropteroate and L-glutamic acid to dihydrofolate.  Finally, the DHFR domain of the bifunctional enzyme dihydrofolate reductase-thymidylate synthase (DHFR-TS) reduces dihydrofolate to tetrahydrofolate with the help of NADPH and a hydrogen ion."
What is the definition of Molybdenum Cofactor Biosynthesis?,"Molybdenum cofactor biosynthesis is a pathway that begins in the mitochondrial matrix and ends in the cytosol by which GTP becomes molybdenum cofactor, a metal-containing prosthetic group common to nearly all molybdoenzymes.  Such molybdenum enzymes play important roles in the regulation of the nitrogen, sulfur and carbon cycles (Wikipedia).  First, the enzyme GTP 3',8-cyclase, located in the mitochondrial matrix, catalyzes the conversion of GTP, S-adenosylmethionine, and a reduced electron acceptor to 3′,8-cH2GTP, L-methionine, 5'-deoxyadenosine, an oxidized electron acceptor, and a hydrogen ion with the help of a [4Fe-4S] cluster cofactor.  Second, cyclic pyranopterin monophosphate (cPMP) synthase catalyzes the conversion of 3′,8-cH2GTP to cPMP and pyrophosphate.  Next, ABC transporter of the mitochondrion 3 (ATM3) exports cPMP from the mitochondrial matrix into the cytosol where it is acted upon by molybdopterin (MPT) synthase.  MPT synthase is a heterotetramer composed of 2 large and 2 small subunits.  The two small subunits are thiocarboxylated by molydopterin synthase sulfurtransferase, and each transfers a sulfur to cPMP to generate the dithiolene in molybdopterin and releasing hydrogen ion in the process.  The following enzyme in the pathway, molybdenum insertase is a two-domain protein that catalyzes the fourth and fifth reactions. The smaller C-terminal Cnx1G domain functions as a molybdopterin molybdotransferase and activates molybdopterin for molybdenum insertion. The product of this reaction, molybdopterin adenine dinucleotide (MPT-AMP), is then transferred to the larger N-terminal Cnx1E domain which exhibits molybdopterin adenylyltransferase activity and inserts molybdenum into the dithiolene of molybdopterin, creating molybdenum cofactor (Moco). Molybdenum insertase requires a divalent cation (e.g. magnesium) as a cofactor."
What is the definition of 5-Deoxystrigol Biosynthesis?,"5-Deoxystrigol Biosynthesis is a pathway that has not yet become fully elucidated.  Beginning in the chloroplast and potentially finishing in the cytosol, the pathway follows the synthesis of 5-deoxystrigol from beta-carotene.  5-Deoxystrigol is a strigolactone, a plant hormone that stimulates the branching and growth of symbiotic arbuscular mycorrhizal fungi and inhibits plant shoot branching.  Strigolactones share a common C19 structure composed of a tricyclic lactone (A, B, and C rings) connected to a second lactone (D ring) by an enol ether bridge.  5-deoxystrigol is the precursor of other beta-oriented C-ring strigolactones (strigol-configured strigolactones) (PMID: 25425668).  First, beta-carotene isomerase catalyzes the conversion of beta-carotene into 9-cis-beta-carotene with the help of an iron cofactor.  Second, 9-cis-beta-carotene 9',10'-cleavage dioxygenase converts 9-cis-beta-carotene and oxygen to 9-cis-10'-apo-beta-carotenal and beta-ionone with the help of an Fe2+ cofactor.  Third, carlactone synthase converts 9-cis-10'-apo-beta-carotenal and oxygen to carlactone and (2E,4E,6E)-7-hydroxy-4-methylhepta-2,4,6-trienal with the help of an Fe2+ cofactor.  The final two reactions are not completely understood and may occur in the cytosol.  Cytochrome P450 monooxygenase is theorized to catalyze the fourth reaction whereby carlactone is conveted into carlactone carboxylate. It requires heme as a cofactor. This same enzyme could possibly also catalyze the fifth reaction in which 5-deoxystrigol is made."
What is the definition of Abscisic Acid Biosynthesis?,"Abscisic acid biosynthesis is a pathway that begins in the chloroplast and ends in the cytosol by which violaxanthin becomes abscisic acid, a plant hormone that plays a role in  many plant developmental processes, including bud dormancy (Wikipedia).  First, neoxanthin synthase catalyzes the opening of the violaxanthin epoxide ring to form neoxanthin.  Second, a yet unidentified neoxanthin isomerase is theorized to isomerize neoxanthin to 9'-cis-neoxanthin.  Third, 9-cis-epoxycarotenoid dioxygenase (NCED) uses oxygen to cleave 9'-cis-neoxanthin to form xanthoxin and C25-allenic-apo-aldehyde.  This enzyme requires Fe2+ as a cofactor.  Next, a xanthoxin transporter is theorized to export xanthoxin from the chloroplast into the cytosol to continue abscisic acid biosynthesis, but it has yet to be discovered.  Fourth, xanthoxin dehydrogenase, located in the cytosol, catalyzes the conversion of  xanthoxin and NAD to abscisic aldehyde, NADH, and a proton with the help of a molybdenum cofactor (MoCo).  Fifth, abscisic-aldehyde oxidase converts abscisic aldehyde, water, and oxygen into hydrogen peroxide, hydrogen ion, and abscisic acid."
What is the definition of Flavonoid Biosynthesis?,"Flavonoids are secondary metabolites with a 15-carbon skeleton consisting of two phenyl rings (A and B) and one heterocyclic ring (C) involved in UV filtration, symbiotic nitrogen fixation, and floral pigmentation.  They may also act as chemical messengers, physiological regulators, and cell cycle inhibitors (Wikipedia).  Flavonoid biosynthesis, by which products from phenylpropanoid biosynthesis (e.g. cinnamoyl-CoA and coumaroyl-CoA) form many different flavonoid products, occurs primarily in the cytoplasm and endoplasmic reticulum. For simplicity, endoplasmic-reticulum-associated enzymes are coloured dark green in the pathway diagram. Further modifications to anthocyanins take place in the chloroplast. The majority of flavonoid derivatives are created from a common set of enzymes that form a flavonoid scaffold. Following the conversion of coumaroyl-CoA into the flavan-3-ol epiafzelechin as an example, the first reaction is catalyzed by chalcone synthase (CHS) in which coumaroyl-CoA is converted into chalconaringenin (naringenin chalcone). Second, chalcone isomerase (CHI) converts chalconaringenin into naringenin (a flavanone). Third, flavanone 3-hydroxylase (F3H), catalyzes the conversion of naringenin into aromadendrin (dihydrokaempferol). Fourth, dihydroflavonol 4-reductase (DFRA) converts aromadendrin into leucopelargonidin (a leucoanthocyanidin). Fifth, leucocyanidin oxygenase (LDOX) catalyzes the conversion of leucopelargonidin into pelargonidin (an anthocyanin). After transport into the chloroplast, pelargonidin is converted into epiafzelechin (a flavan-3-ol) by anthocyanidin reductase (ANR)."
What is the definition of Flavone and Flavonol Biosynthesis?,"Flavonols are a class of flavonoids that have a flavone backbone and a C3 hydroxyl group. These compounds can be found in many fruits and vegetables. This pathway, whereby flavones and flavonols are synthesized and modified, occurs in the cytoplasm and only has a single endoplasmic-reticulum-associated enzyme (flavonoid 3'-hydroxylase) which is coloured dark green in the pathway image.  Flavonoid 3'-hydroxylase converts apigenin, aromadendrin (dihydrokaempferol), and kaempferol into luteolin, taxifolin (dihydroquercetin), and quercetin, respectively.  Flavonol synthase (FLS) uses oxoglutaric acid and oxygen to catalyze the conversion of dihydroflavonols from flavonols.  Requiring Fe2+ and ascorbate as cofactors, FLS converts dihydroquercetin (taxifolin) into quercetin and dihydrokaempferol (aromadendrin) into kaempferol, producing succinic acid, carbon dioxide, and water as byproducts.  Four modifications to the flavonol, quercetin, include sulfonation, methylation, glycosylation, and rhamnosylation. Gglycosylation and rhamnosylation are carried out in the chloroplast. Quercetin 3-sulfotransferase utilizes 3'-phosphoadenylyl-sulfate (PAPS) to transfer a sulfate group to quercetin which forms quercetin 3-sulfate.  This reaction produces adenosine 3',5'-diphosphate as a byproduct.  Quercetin 3'-O-methyltransferase uses S-adenosylmethionine to methylate quercetin to produce isorhamnetin and S-adenosylhomocysteine. Flavonol 3-O-glucosyltransferase catalyzes the conversion of quercetin into isoquercitrin. Flavonol-3-O-rhamnosyltransferase catalyzes two successive reactions to convert quercetin first into quercitrin and then second into quercetin 3-O-rhamnoside 7-O-glucoside. Kaempferol also undergoes modifications such as glycosylation and rhamnosylation. Flavonol 3-O-glucosyltransferase catalyzes the conversion of kaempferol into astragalin. Flavonol-3-O-rhamnosyltransferase catalyzes two successive reactions to convert kaempferol first into afzelin (kaempferin) and then second into kaempferol 3-O-rhamnoside-7-O-glucoside."
What is the definition of Choline Biosynthesis I?,"Choline is a nitrogen-containing, water-soluble nutrient that is incorporated into the headgroups of membrane phospholipids such as phosphatidylcholine.  Two pathways exist for choline biosynthesis whereby serine becomes choline.  Both of these pathways take place in the cytosol.  This is the first pathway of choline biosynthesis.  First, serine decarboxylase (SDC) uses a proton and a pyridoxal 5'-phosphate cofactor to catalyze the conversion of L-serine to ethanolamine, producing carbon dioxide as a byproduct.  Second, ethanolamine kinase, localized to the cell membrane (coloured dark green in the image), uses ATP to catalyze the conversion of ethanolamine to O-phosphoethanolamine.  Note that this is only the probable ethanolamine kinase in Arabidopsis thaliana and requires further research to confirm its function.  Steps 3, 4, and 5  are catalyzed by phosphoethanolamine N-methyltransferase (PEAMT).  These three sequential N-methylation steps convert phosphoethanolamine to phosphocholine and utilize S-adenosyl-L-methionine as a methyl donor.  The intermediates are as follows: O-Phosphoethanolamine, N-methylethanolamine phosphate, and N-dimethylethanolamine phosphate.  Sixth, phosphoethanolamine/phosphocholine phosphatase catalyzes the synthesis of choline from phosphocholine.  It requires magnesium as a cofactor."
What is the definition of Choline Biosynthesis II?,"Choline is a nitrogen-containing, water-soluble nutrient that is incorporated into the headgroups of membrane phospholipids such as phosphatidylcholine. Two pathways exist for choline biosynthesis whereby serine becomes choline.  Both of these pathways take place in the cytosol.  This is the second pathway of choline biosynthesis.  First, serine decarboxylase (SDC) uses a proton and a pyridoxal 5'-phosphate cofactor to catalyze the conversion of L-serine to ethanolamine, producing carbon dioxide as a byproduct.  Second, ethanolamine kinase, localized to the cell membrane (coloured dark green in the image), uses ATP to catalyze the conversion of ethanolamine to O-phosphoethanolamine.  Note that this is only the probable ethanolamine kinase in Arabidopsis thaliana and requires further research to confirm its function.  Steps 3, 4, and 5  are catalyzed by phosphoethanolamine N-methyltransferase (PEAMT).  These three sequential N-methylation steps convert phosphoethanolamine to phosphocholine and utilize S-adenosyl-L-methionine as a methyl donor.  The intermediates are as follows: O-Phosphoethanolamine, N-methylethanolamine phosphate, and N-dimethylethanolamine phosphate.  Sixth, choline-phosphate cytidylyltransferase (CCT) uses CTP to convert phosphocholine to CDP-choline.  Seventh, choline/ethanolaminephosphotransferase (AAPT) uses a 1,2-diacyl-sn-glycerol and either magnesium or manganese ions as cofactors to convert CDP-choline into a phosphatidyl choline, producing CMP and a proton as byproducts.  Eighth, phospholipase D uses a calcium cofactor and water to convert a phosphatidylcholine to choline, producing a 1,2-diacyl-sn-glycerol 3-phosphate and a proton as byproducts."
What is the definition of Phytate Biosynthesis?,"Phytate biosynthesis is a pathway that occurs in the cytosol by which myo-inositol becomes D-myo-inositol (1,3,4)-trisphosphate becomes phytate, the principal storage form of phosphorus in many plant tissues (Wikipedia).  First, myo-inositol-1,3,4-trisphosphate 5/6-kinase uses ATP to catalyze the conversion of D-myo-inositol (1,3,4)-trisphosphate into either D-myo-inositol (1,3,4,6)-tetrakisphosphate or D-myo-inositol (1,3,4,5)-tetrakisphosphate.  It requires magnesium ion as a cofactor.  Second, inositol polyphosphate multiple-kinase uses ATP to catalyze the conversion of either D-myo-inositol (1,3,4,6)-tetrakisphosphate or D-myo-inositol (1,3,4,5)-tetrakisphosphate into D-myo-inositol 1,3,4,5,6-pentakisphosphate.  Third, polyphosphate 2-kinase uses ATP to catalyze the conversion of D-myo-inositol 1,3,4,5,6-pentakisphosphate into phytate. It requires zinc ion as a cofactor."
"What is the definition of D-myo-Inositol (1,4,5)-Trisphosphate Biosynthesis?","D-myo-inositol (1,4,5)-trisphosphate biosynthesis is a pathway that occurs in the cytosol by which myo-inositol becomes D-myo-inositol (1,4,5)-trisphosphate (IP3), a secondary messenger molecule used in signal transduction and lipid signaling in biological cells (Wikipedia).  This pathway consists of a few cell membrane-associated enzymes (coloured dark green in the image): phosphatidylinositol 4-phosphate 5-kinase and phosphoinositide phospholipase C.  First, phosphatidylinositol synthase uses a a CDP-diacylglycerol  to catalyze a reaction whereby myo-inositol is converted into an an L-1-phosphatidyl-inositol. It requires magnesium or manganese ions as cofactors.  Second, phosphatidylinositol 4-kinase uses ATP to catalyze the conversion of an L-1-phosphatidyl-inositol to a 1-phosphatidyl-1D-myo-inositol 4-phosphate.  Third, phosphatidylinositol 4-phosphate 5-kinase uses ATP to catalyze the conversion of a 1-phosphatidyl-1D-myo-inositol 4-phosphate to a 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate.  Alternatively, 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate is predicted to be synthesized by a still undiscovered phosphatidylinositol-5-phosphate 4-kinase from ATP and a 1-phosphatidyl-1D-myo-inositol 5-phosphate.  Finally, phosphoinositide phospholipase C uses water to catalyze the conversion of a 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate to D-myo-inositol (1,4,5)-trisphosphate, producing 1,2-diacyl-sn-glycerol and a proton as byproducts.  Phosphoinositide phospholipase C requires calcium as a cofactor."
What is the definition of Anthocyanidin Sambubioside Biosynthesis?,"Anthocyanidin sambubioside biosynthesis is a pathway by which anthocyanins (plant pigments) become sambubiosides, diglucosides containing an attached xylose on the 2''-O-position of the 3-O-glucose moiety of anthocyanidins.  First, anthocyanidin 3-O-glucoside 2'''-O-xylosyltransferase uses UDP to convert delphinidin 3-glucoside into delphinidin 3-sambubioside, cyanidin 3-glucoside into cyanidin 3-sambubioside, and pelargonidin 3-glucoside into pelargonidin-3-sambubioside.  Second, the predicted enzyme anthocyanin 3-O-sambubioside 5-O-glucosyltransferase (coloured orange) is theorized to use UDP to convert cyanidin 3-sambubioside into cyanidin 3-sambubioside 5-glucoside and pelargonidin-3-sambubioside into pelargonidin 3-sambubioside-5-glucoside."
What is the definition of Neophaseic Acid Biosynthesis?,"Neophaseic acid biosynthesis is a pathway that begins in the chloroplast and ends in the cytosol by which violaxanthin becomes neophaseate, synthesizing abscisic acid in the process.  Neophaseate is an abscisic acid derivative whose synthesis provides a mechanism for controlling abscisic acid concentration.  First, neoxanthin synthase catalyzes the opening of the violaxanthin epoxide ring to form neoxanthin. Second, a yet unidentified neoxanthin isomerase is theorized to isomerize neoxanthin to 9'-cis-neoxanthin. Third, 9-cis-epoxycarotenoid dioxygenase (NCED) uses oxygen to cleave 9'-cis-neoxanthin to form xanthoxin and C25-allenic-apo-aldehyde. This enzyme requires Fe2+ as a cofactor. Next, a xanthoxin transporter is theorized to export xanthoxin from the chloroplast into the cytosol to continue abscisic acid biosynthesis, but it has yet to be discovered. Fourth, xanthoxin dehydrogenase, located in the cytosol, catalyzes the conversion of xanthoxin and NAD to abscisic aldehyde, NADH, and a proton with the help of a molybdenum cofactor (MoCo). Fifth, abscisic-aldehyde oxidase converts abscisic aldehyde, water, and oxygen into hydrogen peroxide, hydrogen ion, and abscisic acid.  Sixth, abscisic acid 8'-hydroxylase / abscisic acid 9'-hydroxylase uses NADPH, oxygen, and a proton to convert abscisic acid into 9'-hydroxyabscisate and water.  Seventh, 9'-hydroxyabscisate spontaneously becomes neophaseate."
What is the definition of Phaseic Acid Biosynthesis?,"Phaseic acid biosynthesis is a pathway that begins in the chloroplast and ends in the cytosol by which violaxanthin becomes phaseic acid (PA) and its derivative dihydrophaseic acid (DPA), synthesizing abscisic acid in the process.  PA and DPA are inactive forms of abscisic acid whose synthesis provides a mechanism for controlling abscisic acid concentration. First, neoxanthin synthase catalyzes the opening of the violaxanthin epoxide ring to form neoxanthin. Second, a yet unidentified neoxanthin isomerase is theorized to isomerize neoxanthin to 9'-cis-neoxanthin. Third, 9-cis-epoxycarotenoid dioxygenase (NCED) uses oxygen to cleave 9'-cis-neoxanthin to form xanthoxin and C25-allenic-apo-aldehyde. This enzyme requires Fe2+ as a cofactor. Next, a xanthoxin transporter is theorized to export xanthoxin from the chloroplast into the cytosol to continue abscisic acid biosynthesis, but it has yet to be discovered. Fourth, xanthoxin dehydrogenase, located in the cytosol, catalyzes the conversion of xanthoxin and NAD to abscisic aldehyde, NADH, and a proton with the help of a molybdenum cofactor (MoCo). Fifth, abscisic-aldehyde oxidase converts abscisic aldehyde, water, and oxygen into hydrogen peroxide, hydrogen ion, and abscisic acid.  Sixth, abscisic acid 8'-hydroxylase / abscisic acid 9'-hydroxylase uses NADPH, oxygen, and a proton to convert abscisic acid into 8'-hydroxyabscisate and water.  Seventh, 8'-hydroxyabscisate spontaneously becomes phaseic acid.  Eighth, the predicted enzyme phaseic acid reductase (coloured orange in the image) is theorized to catalyze the conversion of phaseic acid into dihydroxyphaseic acid."
What is the definition of Abscisic Acid Glucose Ester Metabolism?,"Abscisic acid glucose ester metabolism is a pathway that begins in the chloroplast and enters the cytosol and endoplasmic reticulum body by which violaxanthin becomes abscisic acid glucose ester, synthesizing abscisic acid in the process. Abscisic acid glucose ester synthesis and reformation back to abscisic acid provides a mechanism for precisely controlling abscisic acid concentration (quickly removing and adding abscisic acid when required).  First, neoxanthin synthase catalyzes the opening of the violaxanthin epoxide ring to form neoxanthin. Second, a yet unidentified neoxanthin isomerase is theorized to isomerize neoxanthin to 9'-cis-neoxanthin. Third, 9-cis-epoxycarotenoid dioxygenase (NCED) uses oxygen to cleave 9'-cis-neoxanthin to form xanthoxin and C25-allenic-apo-aldehyde. This enzyme requires Fe2+ as a cofactor. Next, a xanthoxin transporter is theorized to export xanthoxin from the chloroplast into the cytosol to continue abscisic acid biosynthesis, but it has yet to be discovered. Fourth, xanthoxin dehydrogenase, located in the cytosol, catalyzes the conversion of xanthoxin and NAD to abscisic aldehyde, NADH, and a proton with the help of a molybdenum cofactor (MoCo). Fifth, abscisic-aldehyde oxidase converts abscisic aldehyde, water, and oxygen into hydrogen peroxide, hydrogen ion, and abscisic acid.  Sixth, abscisic acid glucosyltransferase uses UDP to convert abscisic acid into abscisic acid glucose ester.  Abscisic acid glucose ester can then be converted back to abscisic acid via abscisic acid glucose ester beta-glucosidase located in the endoplasmic reticulum body (coloured dark green in the image).  Consequently, it is theorized that ABA-GE transporters are required for this enzyme to access its substrates from the cytosol."
What is the definition of Zeaxanthin Biosynthesis?,"Zeaxanthin biosynthesis is a pathway that occurs in the chloroplast by which lycopene becomes zeaxanthin, one of the most common carotenoid alcohols found in nature (Wikipedia).  The first two reactions are catalyzed by lycopene beta cyclase which uses NAD(P)H as a cofactor to convert lycopene into gamma-carotene and gamma-carotene into beta-carotene. The last two reactions are catalyzed by beta-carotene 3-hydroxylase which uses ferredoxin and Fe2+ as cofactors to convert beta-carotene into beta-cryptoxanthin and beta-cryptoxanthin into zeaxanthin."
What is the definition of Xanthophyll Cycle?,"Xanthophyll cycle is a pathway that transforms zeaxanthin to violaxanthin and antheraxanthin through enzymes. Xanthophyll cycle mainly takes place in diatoms and dinoflagellates of plants in high-light condition. Zeaxanthin is obatined from zeaxanthin biosynthesis that transforms lycopene to zeaxanthin (indirectly). Zeaxanthin is catalyzed into antheraxanthin and antheraxanthin catalyzed into violaxanthin both by the enzyme, zeaxanthin epoxidase with cofactor FAD. Violaxanthin deepoxidase/antheraxanthin deepoxidase can reverse the above reactions (i.e. violaxanthin to antheraxanthin and antheraxanthin to zeaxanthin)."
What is the definition of Chlorophyll a Biosynthesis II?,"Chlorophyll a is the primary form of chlorophyll in plants. Chlorophylls are pigments that give plants their perceived green colour and are essential for photosynthesis, the process by which light energy is converted into chemical energy. Chlorophyll a, in particular, absorbs energy from wavelengths of violet-blue and orange-red light. Two pathways exist for chlorophyll a biosynthesis whereby geranylgeranyl diphosphate and 3,8-divinyl chlorophyllide a becomes chlorophyll a. Both of these pathways take place in the chloroplast. This is the second pathway of chlorophyll a biosynthesis.  First, 3,8-divinyl protochlorophyllide a 8-vinyl-reductase converts 3,8-divinyl chlorophyllide into chlorophyllide a.  Second, chlorophyll synthetase uses magnesium ion as a cofactor to convert chlorophyllide a and geranylgeranyl diphosphate into geranylgeranyl chlorophyll a.  The next three reactions to synthesize chlorophyll a from geranylgeranyl chlorophyll a are catalyzed by the same enzyme, geranylgeranyl dehydrogenase. It converts geranylgeranyl chlorophyll a into dihydrogeranylgeranyl chlorophyll a, dihydrogeranylgeranyl chlorophyll a into tetrahydrogeranylgeranyl chlorophyll a, and tetrahydrogeranylgeranyl chlorophyll a into chlorophyll a."
What is the definition of Phylloquinol Biosynthesis?,"Phylloquinol biosynthesis is a pathway that occurs in the cytoplast by which geranylgeranyl diphosphate and 2-carboxy-1,4-naphthoquinol becomes phylloquinol, a naphtoquinone designated as vitamin K1 (along with phylloquinone) which posttranslatonally modifies precursors for blood coagualation.  The three reactions of the subpathway to synthesize phytyl diphosphate from geranylgeranyl diphosphate are catalyzed by the same enzyme, geranylgeranyl dehydrogenase.  This enzyme converts geranylgeranyl diphosphate into dihydrogeranylgeranyl diphosphate, dihydrogeranylgeranyl diphosphate into tetrahydrogeranylgeranyl diphosphate, and tetrahydrogeranylgeranyl diphosphate into phytyl diphosphate.  The single reaction of the subpathway to synthesize 2-carboxy-1,4-naphthoquinone from 2-carboxy-1,4-naphthoquinol is catalyzed by 2-carboxy-1,4-naphthoquinol reductase.  Next, the chloroplast-membrane-associated enzyme 2-carboxy-1,4-naphthoquinone phytyltransferase (coloured dark green in the image) converts phytyl diphosphate and 2-carboxy-1,4-naphthoquinone into demethylphylloquinone.  Then, demethylphylloquinone dehydrogenase uses FAD as a cofactor to convert demethylphylloquinone into demethylphylloquinol.  Lastly, demethylphylloquinol methyltransferase converts demethylphylloquinol into phylloquinol."
What is the definition of Epoxysqualene Biosynthesis?,"Epoxysqualene biosynthesis is a pathway that begins in the chloroplast and finishes on the cytosolic side of the endoplasmic reticulum (coloured dark green in the image) by which isopentenyl diphosphate becomes 2,3-epoxisqualene, an intermediate in the synthesis of the cell membrane sterol precursor cycloartenol (Wikipedia).  First, isopentenyl diphosphate isomerase catalyzes the reversible synthesis of dimethylallyl diphosphate from isopentenyl diphosphate. This enzyme requires FAD, NAD(P)H, and a divalent cation (e.g. magnesium) as cofactors.  Second, geranylpyrophosphate uses magnesium ion as a cofactor to convert dimethylallyl diphosphate into geranyl diphosphate. Third, (2E,6E)-farnesyl diphosphate synthase catalyzes the conversion of geranyl diphosphate into farnesyl diphosphate.  Farnesyl diphosphate then must be transported out of the chloroplast and into the cytosol via a predicted farnesyl diphosphate transporter.  Fourth, squalene synthase uses a magnesium or manganese ion as a cofactor to catalyze the conversion of two farnesyl diphosphates into squalene. Fifth, squalene monooxygenase uses FAD as a cofactor to catalyze the conversion of squalene into 2,3-epoxisqualene. "
What is the definition of Plastoquinol-9 Biosynthesis?,"Plastoquinol-9 biosynthesis is a pathway that begins in the cytosol and endoplasmic reticulum and ends in the chloroplast by which L-tyrosine and geranylgeranyl diphosphate become plastoquinol-9, ubiquinone analogs and benzoquinone electron carriers.  The subpathway that synthesizes homogentisate from L-tryptophan occurs in the cytosol.  First, tryptophan aminotransferase uses a pyridoxal 5'-phosphate as a cofactor to convert L-tryptophan into 4-hydroxyphenylpyruvate. Second, 4-hydroxyphenylpyruvate dioxygenase uses Fe2+ as a cofactor to convert 4-hydroxyphenylpyruvate into homogentisate.  The subpathway that synthesizes solanesyl diphosphate from geranylgeranyl diphosphate occurs in the endoplasmic reticulum and the single reaction is catalyzed by solanesyl diphosphate which requires a magnesium ion as a cofactor.  Solanesyl diphosphate must then be transported out of the endoplasmic reticulum into the cytosol by a yet undiscovered solanesyl diphosphate transporter.  The last two reactions are localized to the chloroplast inner membrane (coloured dark green in the image).  First, homogentisate solanesyltransferase catalyzes the conversion of solanesyl diphosphate and homogentisate into 2-methyl-6-solanesyl-1,4-benzoquinol, requiring magnesium ion as a cofactor.  Second, 2-methyl-6-phytyl-1,4-hydroquinone methyltransferase catalyzes the conversion of 2-methyl-6-solanesyl-1,4-benzoquinol into plastoquinol-9."
What is the definition of Chlorophyll a Degradation II?,"Chlorophyll a degradation is the process in leaf senescence and fruit ripening observable due to its characteristic loss of green colouring.  There are two pathways for chlorophyll a degradation.  This second pathway, occurring in the chloroplast, is possibly the primary route by which chlorophyll a undergoes degradation in senescing leaves.  First, the predicted enzyme pheophytin a synthase (coloured orange in the image) is theorized to dechelate Mg2+ in chlorophyll a to form pheophytin a.  Second, pheophytinase catalyzes teh conversion of pheophytin into pheophorbide a and phytol.  Third, pheophorbide a oxygenase, localized to the chloroplast membrane (coloured dark green in the image), catalyzes the conversion of pheophorbide into epoxypheophorbide a.  Fourth, epoxypheophorbide and water spontaneously converts into red chlorophyll catabolite.  Fifth, red chlorophyll catabolite reductase (RCCR) converts red chlorophyll catabolite into primary fluorescent chlorophyll catabolite."
What is the definition of Thio-Molybdenum Cofactor Biosynthesis?,"Thio-molybdenum cofactor biosynthesis is a pathway that begins in the mitochondrial matrix and ends in the cytosol by which GTP becomes thio-molybdenum cofactor, the sulfo-form of molybdenum cofactor required by certain plant enzymes.  First, the enzyme GTP 3',8-cyclase, located in the mitochondrial matrix, catalyzes the conversion of GTP, S-adenosylmethionine, and a reduced electron acceptor to 3′,8-cH2GTP, L-methionine, 5'-deoxyadenosine, an oxidized electron acceptor, and a hydrogen ion with the help of a [4Fe-4S] cluster cofactor.  Second, cyclic pyranopterin monophosphate (cPMP) synthase catalyzes the conversion of 3′,8-cH2GTP to cPMP and pyrophosphate.  Next, ABC transporter of the mitochondrion 3 (ATM3) exports cPMP from the mitochondrial matrix into the cytosol where it is acted upon by molybdopterin (MPT) synthase.  MPT synthase is a heterotetramer composed of 2 large and 2 small subunits.  The two small subunits are thiocarboxylated by molydopterin synthase sulfurtransferase, and each transfers a sulfur to cPMP to generate the dithiolene in molybdopterin and releasing hydrogen ion in the process.  The following enzyme in the pathway, molybdenum insertase is a two-domain protein that catalyzes the fourth and fifth reactions. The smaller C-terminal Cnx1G domain functions as a molybdopterin molybdotransferase and activates molybdopterin for molybdenum insertion. The product of this reaction, molybdopterin adenine dinucleotide (MPT-AMP), is then transferred to the larger N-terminal Cnx1E domain which exhibits molybdopterin adenylyltransferase activity and inserts molybdenum into the dithiolene of molybdopterin, creating molybdenum cofactor (Moco). Molybdenum insertase requires a divalent cation (e.g. magnesium) as a cofactor.  Lastly, molybdenum cofactor sulfurtransferase uses L-cysteine and a reduced electron acceptor to convert molybdenum cofactor into thio-molybdenum cofactor, producing L-alanine, oxidized electron acceptor, and water as byproducts. It requires pyridoxal 5'-phosphate as a cofactor."
What is the definition of Glycine Betaine Biosynthesis I?,"Glycine betaine biosynthesis I, beginning in the cytosol and ending in the peroxisome results in the synthesis of glycine betaine from choline produced from the choline biosynthesis I pathway.  Glycine betaine is an amino acid derivative that occurs in plants which serves as a protectant against osmotic stress, mutagenesis, and radiation-induced damage.   First, serine decarboxylase (SDC) uses a proton and a pyridoxal 5'-phosphate cofactor to catalyze the conversion of L-serine to ethanolamine, producing carbon dioxide as a byproduct. Second, ethanolamine kinase, localized to the cell membrane (coloured dark green in the image), uses ATP to catalyze the conversion of ethanolamine to O-phosphoethanolamine. Note that this is only the probable ethanolamine kinase in Arabidopsis thaliana and requires further research to confirm its function. Steps 3, 4, and 5 are catalyzed by phosphoethanolamine N-methyltransferase (PEAMT). These three sequential N-methylation steps convert phosphoethanolamine to phosphocholine and utilize S-adenosyl-L-methionine as a methyl donor. The intermediates are as follows: O-Phosphoethanolamine, N-methylethanolamine phosphate, and N-dimethylethanolamine phosphate. Sixth, phosphoethanolamine/phosphocholine phosphatase catalyzes the synthesis of choline from phosphocholine.  It requires magnesium as a cofactor..  Choline is then theorized to be transported into the peroxisome.  Seventh, choline monooxygenase is a predicted enzyme that is theorized to catalyze the conversion of choline into betaine aldehyde hydrate.  Eighth, betaine aldehyde hydrate spontaneously becomes betaine aldehyde, producing water as a byproduct.  Ninth, betaine aldehyde uses NAD and water to convet betaine aldehyde into glycine betaine."
What is the definition of Glycine Betaine Biosynthesis II?,"Glycine betaine biosynthesis I, beginning in the cytosol and ending in the peroxisome results in the synthesis of glycine betaine from choline produced from the choline biosynthesis I pathway. Glycine betaine is an amino acid derivative that occurs in plants which serves as a protectant against osmotic stress, mutagenesis, and radiation-induced damage.  First, serine decarboxylase (SDC) uses a proton and a pyridoxal 5'-phosphate cofactor to catalyze the conversion of L-serine to ethanolamine, producing carbon dioxide as a byproduct. Second, ethanolamine kinase, localized to the cell membrane (coloured dark green in the image), uses ATP to catalyze the conversion of ethanolamine to O-phosphoethanolamine. Note that this is only the probable ethanolamine kinase in Arabidopsis thaliana and requires further research to confirm its function. Steps 3, 4, and 5 are catalyzed by phosphoethanolamine N-methyltransferase (PEAMT). These three sequential N-methylation steps convert phosphoethanolamine to phosphocholine and utilize S-adenosyl-L-methionine as a methyl donor. The intermediates are as follows: O-Phosphoethanolamine, N-methylethanolamine phosphate, and N-dimethylethanolamine phosphate. Sixth, choline-phosphate cytidylyltransferase (CCT) uses CTP to convert phosphocholine to CDP-choline. Seventh, choline/ethanolaminephosphotransferase (AAPT) uses a 1,2-diacyl-sn-glycerol and either magnesium or manganese ions as cofactors to convert CDP-choline into a phosphatidyl choline, producing CMP and a proton as byproducts. Eighth, phospholipase D uses a calcium cofactor and water to convert a phosphatidylcholine to choline, producing a 1,2-diacyl-sn-glycerol 3-phosphate and a proton as byproducts.  Choline is then theorized to be transported into the peroxisome. Ninth, choline monooxygenase is a predicted enzyme that is theorized to catalyze the conversion of choline into betaine aldehyde hydrate. Tenth, betaine aldehyde hydrate spontaneously becomes betaine aldehyde, producing water as a byproduct. Eleventh, betaine aldehyde uses NAD and water to convet betaine aldehyde into glycine betaine."
What is the definition of Farnesene Biosynthesis?,"Farnesene biosynthesis is a pathway that begins in the chloroplast and ends in the cytosol by which isopentenyl diphosphate becomes a farnesene, a set of six closely related chemical compounds which all are sesquiterpenes. alpha-Farnesene and beta-farnesene are isomers, differing by the location of one double bond.  Two of the alpha-farnesene stereoisomers are reported to occur in nature.  beta-Farnesene has only one naturally occurring isomer (Wikipedia).  First, isopentenyl diphosphate isomerase catalyzes the reversible synthesis of dimethylallyl diphosphate from isopentenyl diphosphate. This enzyme requires FAD, NAD(P)H, and a divalent cation (e.g. magnesium) as cofactors.  Second, geranylpyrophosphate uses magnesium ion as a cofactor to convert dimethylallyl diphosphate into geranyl diphosphate. Third, (2E,6E)-farnesyl diphosphate synthase catalyzes the conversion of geranyl diphosphate into farnesyl diphosphate.  Farnesyl diphosphate then must be transported out of the chloroplast and into the cytosol via a predicted farnesyl diphosphate transporter.  Three different enzymes then convert farnesyl diphosphate into different farnesenes.  (E,E)-alpha-farnesene synthase converts farnesyl diphosphate into (E,E)-alpha-farnesene.  Sesquiterpene synthase converts farnesyl diphosphate into (E)-beta-farnesene.  Both of these enzymes requires a magnesium or manganese ion as cofactors.  A predicted enzyme, (Z,E)-alpha-farnesene synthase is theorized to catalyze the conversion of farnesyl diphosphate into (Z,E)-alpha-farnesene."
What is the definition of Chlorophyll a Biosynthesis I?,"Chlorophyll a is the primary form of chlorophyll in plants. Chlorophylls are pigments that give plants their perceived green colour and are essential for photosynthesis, the process by which light energy is converted into chemical energy. Chlorophyll a, in particular, absorbs energy from wavelengths of violet-blue and orange-red light. Two pathways exist for chlorophyll a biosynthesis whereby geranylgeranyl diphosphate and 3,8-divinyl chlorophyllide a becomes chlorophyll a. Both of these pathways take place in the chloroplast. This is the first pathway of chlorophyll a biosynthesis.  The three reactions of the subpathway to synthesize phytyl diphosphate from geranylgeranyl diphosphate are catalyzed by the same enzyme, geranylgeranyl dehydrogenase.  This enzyme converts geranylgeranyl diphosphate into dihydrogeranylgeranyl diphosphate, dihydrogeranylgeranyl diphosphate into tetrahydrogeranylgeranyl diphosphate, and tetrahydrogeranylgeranyl diphosphate into phytyl diphosphate.  The only reaction in the subpathway to synthesize chlorophyllide a from 3,8-divinyl chlorophyllide a is catalyzed by 3,8-divinyl protochlorophyllide a 8-vinyl-reductase.  Lastly, chlorophyll synthetase converts chlorophyllide into chlorophyll a. It requires a magnesium ion as a cofactor."
What is the definition of Chlorophyll a Degradation I?,"Chlorophyll a degradation is the process in leaf senescence and fruit ripening observable due to its characteristic loss of green colouring. There are two pathways for chlorophyll a degradation. This first pathway, largely occurring in the chloroplast, is hypothesized to be operational during fruit senescence and as an immune respone.  First, chlorophyllase catalyzes the conversion of chlorophyll a into chlorophyllide a and phytol.  Second, the predicted enzyme magnesium dechelatase (coloured orange in the image) is theorized to release Mg2+ from chlorophyllide to form pheophorbide a.  Pheophorbide a has two fates.  Either it is transported out of the chloroplast by a predicted pheophorbide a transporter and converted into pyropheophorbide a by the probable pheophorbidase enzyme (coloured orange in the image) or it it continues on to eventually become a primary fluorescent chlorophyll catabolite.  Continuing along the main branch,    pheophorbide a oxygenase, localized to the chloroplast membrane (coloured dark green in the image), catalyzes the conversion of pheophorbide into epoxypheophorbide a.  Next, epoxypheophorbide and water spontaneously converts into red chlorophyll catabolite.  Last, red chlorophyll catabolite reductase (RCCR) converts red chlorophyll catabolite into primary fluorescent chlorophyll catabolite."
What is the definition of AMP Degradation (Hypoxanthine Route)?,"Purine nucleotides are eventually degraded to ammonia and carbon dioxide.  This pathway follows the degradation of AMP to a urate intermediate in the cytosol via xanthine conversion from hypoxanthine.  First, AMP deaminase catalyzes the conversion of AMP is into IMP.  Second, the predicted enzyme 5′-nucleotidase (coloured orange in the image) is theorized to convert IMP into inosine.  Third, ribonucleoside hydrolase converts inosine into hypoxanthine.  Fourth, xanthine dehydrogenase is an enzyme that requires [2Fe-2S] cluster, FAD, and Moco as cofactors for catalyzing two subsequent reaction in the AMP degradation pathway: the conversion of hypoxanthine into xanthine and the conversion of xanthine into urate."
What is the definition of Urate Degradation to Ureidoglycolate?,"Purine nucleotides are eventually degraded to ammonia and carbon dioxide. This pathway begins in the peroxisome and follows the degradation a urate intermediate to S-ureidoglycolate.  The last two steps take place in the endoplasmic reticulum. First, uricase converts urate into 5-hydroxyisourate.  Steps two and three are catalyzed by the bifunctional enzyme S-allantoin synthase: the conversion of 5-hydroxyisourate into 5-hydroxy-2-oxo-4-ureido-2,5-dihydro-1H-imidazole-5-carboxylate (OHCU) and the conversion of OHCU into S-allantoin.  Fourth, allantoinase requires zinc ion as a cofactor to catalyze the conversion of S-allantoin into allantoate.  Next allantoate must be transported out of the peroxisome and into the endoplasmic reticulum.  Fifth, allantoate amidohydrolase catalyzes the conversion of allantoate into S-ureidoglycine. This enzyme is a homodimer and requires manganese ion as a cofactor.  Sixth, ureidoglycine aminohydrolase requires a manganese ion as a cofactor to catalyze the conversion of S-ureidoglycine into S-ureidoglycolate. "
What is the definition of cis-Zeatin-O-Glucoside Biosynthesis?,"Cytokinins (CK) are a class of plant growth substances (phytohormones) that promote cell division, or cytokinesis, in plant roots and shoots. They are involved primarily in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and leaf senescence.  Zeatin is an adenine-type cytokinin (Wikipedia).  The synthesis of cis-type cytokinins is carried out in the cytosol through prenylation of tRNA molecules and dimethylallyl diphosphate precursors provided through the mevalonate pathway.  Hormonal homeostasis is thought to be maintained by glucosylation that inactivates cytokinins.  O-glucosylation is reversible and is hypothesized to be involved with transport, storage, and protection against zeatin oxidases.  Only the enzymes that catalyze the first and last steps of this pathway have been elucidated (all predicted enzymes are coloured orange in the image).  First, tRNA dimethylallyltransferase transfers a dimethylallyl group onto the adenine at position 37 in tRNAs that have uridine-starting codons. It requires a magnesium ion as a cofactor.  Second, the predicted enzyme cis-Hydroxy-prenyl-tRNA catalyzes a reaction whereby N6-dimethylallyladenosine37 in tRNA is converted into cis-hydroxy-prenyl-tRNA.  Third, the predicted enzyme cZRMP synthase catalyzes a reaction whereby cis-hydroxy-prenyl-tRNA is converted into cis-zeatin riboside monophosphate (cZRMP).  Fourth, the predicted enzyme cis-Zeatin riboside synthase catalyzes a reaction whereby cis-zeatin riboside monophosphate (cZRMP) is converted into cis-zeatin riboside.  Fifth, the predicted enzyme cis-Zeatin synthase catalyzes whereby cis-zeatin riboside is converted into cis-zeatin.  Sixth, UDP glucose:cytokinin glycosyltransferase catalyzes a reaction whereby cis-zeatin is converted into cis-zeatin-O-glucoside."
What is the definition of CMP-3-Deoxy-D-Manno-Octulosonate (CMP-Kdo) Biosynthesis?,"CMP-3-deoxy-D-manno-octulosonate (CMP-Kdo) biosynthesis is a pathway that occurs in the cytosol by which D-ribulose 5-phosphate becomes CMP-3-deoxy-D-manno-octulosonate (CMP-Kdo).  Kdo is a component in the plant cell wall, specifically of pectic polysaccharide rhamnogalacturonan II.  First, arabinose-5-phosphate isomerase catalyzes the conversion of D-ribulose 5-phosphate to D-arabinose 5-phosphate.  Second, D-arabinose 5-phosphate is spontaneously converted into D-arabinofuranose 5-phosphate.  Third, 3-deoxy-8-phosphooctulonate synthase converts D-arabinofuranose 5-phosphate into 3-deoxy-D-manno-octulosonate 8-phosphate (KDO-8P). This enzme is a homotetramer.  Fourth, the predicted enzyme 3-deoxy-manno-octulosonate-8-phosphatase (coloured orange in the image) is theorized to catalyze the conversion of 3-deoxy-D-manno-octulosonate 8-phosphate (KDO-8P) into 3-deoxy-D-manno-2-octulosonate (Kdo).  The last reaction is localized to the mitochondria outer membrane whereby 3-deoxy-manno-octulosonate cytidylyltransferase (coloured dark green in the image) catalyzes the conversion of 3-deoxy-D-manno-2-octulosonate (Kdo) into CMP-3-deoxy-D-manno-octulosonate (CMP-Kdo). This enzyme requires a magnesium ion as a cofactor."
What is the definition of Cytokinins Degradation?,"Cytokinins (CK) are a class of plant growth substances (phytohormones) that promote cell division, or cytokinesis, in plant roots and shoots. They are involved primarily in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and leaf senescence. (Wikipedia).  Their regulation can take the form of biosynthesis, import, conjugation, and degradation.  Homeostasis regulation by irreversible degradation is carried out by cytokinin oxidases which form adenine-like compounds resulting from the cleavage of the N6-isopentenyl-side chain.  The cytokinins degradation pathway consists of five different degradation reactions that can be localized to either the endoplasmic reticulum or the vacuole.  Cytokinin oxidase was found to catalyze two such reactions: the conversion of N6-dimethylallyladenine into 3-methyl-2-butenal and adenine and the conversion of trans-zeatin into 3-methyl-4-trans-hydroxy-2-butenal and adenine.  It has not yet been determined if cytokinin oxidase also catalyzes the other three reactions in the cytokinins degradation pathway: the conversion of isopentenyl adenosine into adenosine and 3-methyl-2-butenal, the conversion of cis-zeatin into 3-methyl-4-cis-hydroxy-2-butenal and adenine, and the conversion of trans-zeatin riboside into 3-methyl-4-trans-hydroxy-2-butenal and adenosine.  As such, the enzyme of these reactions are coloured orange in the image."
What is the definition of D-Galactose Degradation (Leloir pathway)?,"The Leloir pathway is a metabolic pathway for the catabolism of D-galactose into D-glucopyranose 6-phosphate named after Luis Federico Leloir (Wikipedia).  Since galactose cannot be directly used for glycolysis, it needs to be converted into a different form.  This pathway starts in the cytosol and finishes in the chloroplast.  First, aldose 1-epimerase is a predicted enzyme (coloured orange in the image) that is theorized to catalyze the conversion of beta-D-galactose into alpha-D-galactose. This enzyme has not yet been elucidated for Arabidopsis thaliana.  Second, galactokinase catalyzes the conversion of alpha-D-galactose into alpha-D-galactose 1-phosphate.  Third, D-galactose-1-phosphate uridylyltransferase is a predicted enzyme theorized to catalyze the reaction whereby alpha-D-galactose 1-phosphate and UDP-glucose is converted into alpha-D-glucopyranose 1-phosphate and UDP-galactose. This enzyme has not yet been elucidated in Arabidopsis thaliana.  UDP-glucose and UDP-galactose can be interconverted by the enzyme UDP-glucose 4-epimerase which requires NAD as a cofactor.  Alpha-D-glucopyranose 1-phosphate must then be imported into the chloroplast, by a yet not discovered alpha-D-glucopyranose 1-phosphate transporter.  Last, phosphoglucomutase uses magnesium ion as a cofactor to convert alpha-D-glucopyranose 1-phosphate into D-glucopyranose 6-phosphate."
What is the definition of Fatty Acid Beta-Oxidation II?,"Beta-oxidation is the catabolic process of the break down of fatty acid molecules in peroxisomes in plants to produce acetyl-CoA to enter the citric acid cycle. Co-enzyme NADH is also generated by the pathway for use in the electron transport chain. The pathway is named after the oxidation of the beta carbon of the fatty acid to a carbonyl group. Multiple different degradation routes exist and this is an offshoot of the core oxidation cycle for unsaturated fatty acids with cis-double bonds on odd-number carbons.  After two rounds of core beta oxidation, such fatty acids are converted into cis-5-enoyl-CoA and enter this degradation pathway thereby exiting the core oxidation pathway.  This exit is marked by their conversion into a trans-2,cis-5-dienoyl-CoA catalyzed by an acyl coenzyme A oxidase.  Second, a yet not elucidated dodecenoyl-CoA isomerase (coloured orange in the image) is theorized to catalyze the conversion of a trans2,cis-5-dienoyl-CoA into a trans3,cis-5-dienoyl-CoA.  Third, delta3,5-delta2,4-dienoyl-CoA isomerase catalyzes the conversion of a trans3,cis-5-dienoyl-CoA into a trans-2,trans-4-dienoyl-CoA.  Fourth, 2,4-dienoyl-CoA reductase is theorized to catalyze the converesion of a trans-2,trans-4-dienoyl-CoA into a trans-3-enoyl-CoA.  Fifth, delta3, delta2-enoyl-CoA isomerase catalyzes the conversion of a a trans-3-enoyl-CoA into a trans-2-enoyl-CoA for re-entry into the core beta oxidation pathway to complete degradation. "
What is the definition of Fatty Acid Elongation?,"Fatty acid elongation consists of the addition of two carbons to a acyl-[acyl-carrier protein] molecule for every turn of the cycle.  The products synthesized as a result of multiple turns of the cycle are used to build fatty acid-containing compounds (e.g. phosphlipids, saturated fatty acids).  This pathway occurs in the chloroplast and predicted enzymes are coloured orange in the image. Upon initial entry into the cycle, a 3-oxoacyl-[acp] is converted into a (3R)-3-hydroxyacyl-[acyl-carrier protein] by 3-oxoacyl-[acyl-carrier-protein] reductase.  Second, a not yet elucidated 3-hydroxyacyl-[acyl-carrier-protein] dehydratase in Arabidopsis thaliana is theorized to catalyze the conversion of a (3R)-3-hydroxyacyl-[acyl-carrier protein] into a trans-2-enoyl-[acyl-carrier protein].  The third reaction by which a trans-2-enoyl-[acyl-carrier protein] is converted into a 2,3,4-saturated fatty acyl-[acp] using NADH can be catalyzed by either a enoyl-[acyl-carrier-protein] reductase (NADH) or a enoyl-[acyl-carrier-protein] reductase (NADPH).  Both enzymes are not yet elucidated in Arabidopsis thaliana.  Last, 3-oxoacyl-[acyl-carrier-protein] synthase I catalyzes the conversion of a 2,3,4-saturated fatty acyl-[acp] converted into a (longer) 3-oxoacyl-[acp] that can lengthen with more turns in the cycle."
What is the definition of Fatty Acid Beta-Oxidation I?,"Beta-oxidation is the catabolic process of the breakdown of fatty acid molecules in peroxisomes in plants to produce acetyl-CoA to enter the citric acid cycle. NADH is also produced by the pathway and is a co-enzyme in the electron transport chain. The pathway name is due to the fatty acid's beta carbon undergoing oxidation to a carbonyl group. Multiple different degradation routes exist and this is a core oxidation cycle.  First, long-chain acyl-CoA synthetase 7 catalyzes the conversion of a 2,3,4-saturated fatty acid into a 2,3,4-saturated fatty acyl CoA. It requires a magnesium ion as a cofactor.  This 2,3,4-saturated fatty acyl CoA then enters a cycle.  Second, the predicted enzyme acyl-CoA oxidase (coloured orange in the image) is theorized to catalyze the conversion of a 2,3,4-saturated fatty acyl CoA into a trans-2-enoyl-CoA.  Third, peroxisomal fatty acid beta-oxidation multifunctional protein AIM1 catalyzes the conversion of a trans-2-enoyl-CoA into a (3S)-3-hydroxyacyl-CoA.  Fourth, peroxisomal fatty acid beta-oxidation multifunctional protein MFP2 catalyzes a reaction whereby a (3S)-3-hydroxyacyl-CoA is converted into a 3-oxoacyl-CoA.  Fifth, OPC4-3-ketoacyl-CoA thiolase catalyzes the conversion of a 3-oxoacyl-CoA into a 2,3,4-saturated fatty acyl CoA."
What is the definition of Folate Polyglutamylation?,"Tetrahydrofolate is an essential cofactor that takes part in various enzymatic reactions as a carrier for one-carbon units.  Most folates are further modified to form folate polyglutamates via consecutive additions of glutamate residues to the their gamma-carboxylate groups.  This can serve many purposes including retention of the folates within the cell and an increase in their binding strength.  Folate (and folate derivatives) polyglutamylation occurs in the cytosol.  Tetrahydrofolate can be synthesized into two derivatives:  a N10-formyl-tetrahydrofolate (catalyzed by 10-formyltetrahydrofolate synthetase) and a 5,10-methylene-tetrahydrofolate (catalyzed by serine hydroxymethyltransferase).  Next, the enzyme polylpolyglutamate synthetase catalyzes the addition of a glutamate residue to tetrahydrofolate (or tetrahydrofolate derviative) in folate polyglutamylation. This includes tetrahydropteroyl-[gamma-Glu](n) becoming tetrahydropteroyl-[gamma-Glu](n+1), methylene-tetrahydropteroyl-[gamma-Glu](n) becoming methylene-tetrahydropteroyl-[gamma-Glu](n+1), and 10-formyl-tetrahydropteroyl-[gamma-Glu](n) becoming 10-formyl-tetrahydropteroyl-[gamma-Glu](n+1).  "
What is the definition of Triacylglycerol Degradation?,"In higher plants, the primary seed storage reserve is triacylglycerol rather than carbohydrates.  Thus, triacylglycerol degradation is an important pathway from which plants obtain energy for growth.  First, triacylglycerol lipase, an enzyme localized to the oil body (storage vacuole) membrane, catalyzes the conversion of a triglyceride into a 1,2-diglyceride.  Second, the predicted enzyme diglyceride lipase (coloured orange in the image) is theorized to catalyze the conversion of a 1,2-diglyceride iinto a 2-acylglycerol.  Third, a 2-acylglycerol is spontaneously converted into a 1-monoglyceride.  Fourth, acylhydrolase catalyzes the conversion of a 1-monoglyceride into glycerol.  Fifth, glycerol kinase catalyzes the conversion of glycerol into glycerol 3-phosphate.  Sixth, glycerol-3-phosphate dehydrogenase (coloured dark green in the image), localized to the mitochondrial inner membrane, catalyzes the conversion of glycerol 3-phosphate into glycerone phosphate."
What is the definition of Galactolipid Biosynthesis?,"Galactolipids are a type of glycolipid whose sugar group is galactose.  They are the main part of plant photosynthetic membrane lipids where they substitute phospholipids to conserve phosphate for other essential processes (Wikipedia).  Their synthesis is localized to the chloroplast membranes (membrane-associated enzymes are coloured dark green in the image).  First, UDP-galactose:DAG galactosyltransferase catalyzes the conversion of a 1,2-diacyl-sn-glycerol into a 1,2-diacyl-3-O-(beta-D-galactopyranosyl)-sn-glycerol.  This compound has two different fates.  The first subpathway consists of a single reaction catalyzed by UDP-galactose:MGDG galactosyltransferase whereby 1,2-diacyl-3-O-(beta-D-galactopyranosyl)-sn-glycerol is converted into an alpha,beta-digalactosyldiacylglycerol.  This enzyme requires a magesium ion as a cofactor.  The second pathway consists of three successive reactions catalyzed by the same enzyme.  Galactolipid:galactolipid galactosyltransferase uses a 1,2-diacyl-3-O-(beta-D-galactopyranosyl)-sn-glycerol to first convert another 1,2-diacyl-3-O-(beta-D-galactopyranosyl)-sn-glycerol into a 1,2-diacyl-3-O-[beta-D-galactosyl-(1→6)-beta-D-galactosyl]-sn-glycerol then into a trigalactosyldiacylglycerol and finally into a tetragalactosyldiacylglycerol."
What is the definition of Urate Degradation to Glyoxylate?,"Purine nucleotides are eventually degraded to ammonia and carbon dioxide. This pathway begins in the peroxisome and follows the degradation a urate intermediate to glyoxylate. The last three steps take place in the endoplasmic reticulum. First, uricase converts urate into 5-hydroxyisourate. Steps two and three are catalyzed by the bifunctional enzyme S-allantoin synthase: the conversion of 5-hydroxyisourate into 5-hydroxy-2-oxo-4-ureido-2,5-dihydro-1H-imidazole-5-carboxylate (OHCU) and the conversion of OHCU into S-allantoin. Fourth, allantoinase requires zinc ion as a cofactor to catalyze the conversion of S-allantoin into allantoate. Next allantoate must be transported out of the peroxisome and into the endoplasmic reticulum. Fifth, allantoate amidohydrolase catalyzes the conversion of allantoate into S-ureidoglycine. This enzyme is a homodimer and requires manganese ion as a cofactor. Sixth, ureidoglycine aminohydrolase requires a manganese ion as a cofactor to catalyze the conversion of S-ureidoglycine into S-ureidoglycolate.  Seventh, ureidoglycolate amidohydrolase catalyzes the conversion of S-ureidoglycolate into glyoxylate."
What is the definition of cis-Zeatin-N-Glucoside Biosynthesis?,"Cytokinins (CK) are a class of plant growth substances (phytohormones) that promote cell division, or cytokinesis, in plant roots and shoots. They are involved primarily in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and leaf senescence.  Zeatin is an adenine-type cytokinin (Wikipedia).  The synthesis of cis-type cytokinins is carried out in the cytosol through prenylation of tRNA molecules and dimethylallyl diphosphate precursors provided through the mevalonate pathway.  Hormonal homeostasis is thought to be maintained by glucosylation that inactivates cytokinins.  N-glucosylation is irreversible and is hypothesized to be involved with detoxification.  Only the enzymes that catalyze the first and last steps of this pathway have been elucidated (all predicted enzymes are coloured orange in the image).  First, tRNA dimethylallyltransferase transfers a dimethylallyl group onto the adenine at position 37 in tRNAs that have uridine-starting codons. It requires a magnesium ion as a cofactor.  Second, the predicted enzyme cis-Hydroxy-prenyl-tRNA catalyzes a reaction whereby N6-dimethylallyladenosine37 in tRNA is converted into cis-hydroxy-prenyl-tRNA.  Third, the predicted enzyme cZRMP synthase catalyzes a reaction whereby cis-hydroxy-prenyl-tRNA is converted into cis-zeatin riboside monophosphate (cZRMP).  Fourth, the predicted enzyme cis-Zeatin riboside synthase catalyzes a reaction whereby cis-zeatin riboside monophosphate (cZRMP) is converted into cis-zeatin riboside.  Fifth, the predicted enzyme cis-Zeatin synthase catalyzes whereby cis-zeatin riboside is converted into cis-zeatin.  Sixth, cytokinin UDP glycosyltransferase catalyzes the two different reactions whereby cis-zeatin is converted into either cis-zeatin-9-N-glucoside or cis-zeatin-7-N-glucoside. "
What is the definition of Gibberellin A12 Biosynthesis?,"Gibberellins (GAs) are a large class of tetracyclic diterpenoid plant hormones that regulate numerous growth and developmental processes, such as seed germination, organ elongation, and flowering induction.  All known gibberellins share an ent-gibberellane skeleton and follow the same synthesis pathway.  Biosynthesis begins in the plasmids via the terpenoid pathway and finishes in the endoplasmic reticulum and cytosol where they undergo modification until a biologically-active form is reached (GA1, GA3, GA4, or GA7).  Gibberellins are named in the order that they are discovered (GA1 through GAn).  Serving as a branch point, the first true gibberellin GA12 is used to synthesize the full range of gibberellins by undergoing a multitude of oxidations and cyclizations.  Gibberellin A12 biosynthesis, beginning at the chloroplast outer membrane and finishing at the endoplasmic reticulum membrane, comprises of six oxidation steps catalyzed by two membrane-associated multifunctional enzymes of the cytochrome P450 family: ent-kaurene oxidase and ent-kaurenoic acid oxidase.  ent-Kaurene oxidase converts ent-kaurene into ent-kaurenoate via three successive oxidations of the 4-methyl group.  ent-Kaurenoate oxidase converts ent-kaurenoate into gibberellin A12 via three successive oxidations at carbon positions C-7 and C-6 in gibberellin A12 biosynthesis."
What is the definition of Gibberellin Biosynthesis I (Early C-3 Hydroxylation)?,"Gibberellins (GAs) are a large class of tetracyclic diterpenoid plant hormones that regulate numerous growth and developmental processes, such as seed germination, organ elongation, and flowering induction. All known gibberellins share an ent-gibberellane skeleton and follow the same synthesis pathway. Biosynthesis begins in the plasmids via the terpenoid pathway and finishes in the endoplasmic reticulum and cytosol where they undergo modification until a biologically-active form is reached (GA1, GA3, GA4, or GA7). Gibberellin biosynthesis via early C-3 hydroxylation occurs in the cytosol and converts the inactive GA12 to the active GA4.  First, a predicted enzyme gibberellin 3beta-hydroxylase (coloured orange in the image)  is theorized to hydroxylate the C3 carbon of gibberellin A12, synthesizing gibberellin A14.  Second, gibberellin 20-oxidase catalyzes the conversion of gibberellin A14 into gibberellin A37.  This is the first of two reactions catalyzed by this enzyme in this pathway.  Gibberellin 20-oxidase requires Fe2+ and L-ascorbate as cofactors.  Alternatively, gibberellin A37 can be synthesized from gibberellin A15 via gibberellin 3-oxidase.  This enzyme also requires Fe2+ and L-ascorbate as cofactors.  Third, the conversion of gibberellin A37 into gibberellin A36 is catalyzed by a yet unelucidated enzyme (unofficially termed gibberellin oxidase for reference purposes).  Last, gibberellin 20-oxidase catalyzes the conversion of gibberellin A36 into the active gibberellin A4."
What is the definition of Gibberellin Biosynthesis II (Early C-13 Hydroxylation)?,"Gibberellins (GAs) are a large class of tetracyclic diterpenoid plant hormones that regulate numerous growth and developmental processes, such as seed germination, organ elongation, and flowering induction. All known gibberellins share an ent-gibberellane skeleton and follow the same synthesis pathway. Biosynthesis begins in the plasmids via the terpenoid pathway and finishes in the endoplasmic reticulum and cytosol where they undergo modification until a biologically-active form is reached (GA1, GA3, GA4, or GA7).  Gibberellin biosynthesis via early C-13 hydroxylation occurs in the cytosol and converts the inactive GA12 to the active GA1.  First, the predicted enzyme gibberellin 13-hydroxylase (coloured orange in the image) is theorized to catalyze the conversion of gibberellin A12 into gibberellin A53.  Second, gibberellin 20-oxidase catalyzes the conversion of gibberellin A53 into gibberellin A44 open lactone, requiring Fe2+ and L-ascorbate as cofactors.  The main fate of gibberellin A44 open lactone is conversion into gibberellin A19 which is catalyzed by the not yet elucidated enzyme gibberellin-44 dioxygenase, requiring Fe3+ as a cofactor.  The secondary fate of gibberellin A44 open lactone is conversion into gibberellin A38 which is catalyzed by gibberellin 3-oxidase, requiring Fe2+ and L-ascorbate as cofactors.  The main fate of gibberellin A19 is conversion into gibberellin A20 and its secondary fate is conversion into gibberellin A17.  These reactions' enzymes have not yet been elucidated and are referred to as simply gibberellin oxidase for reference purposes.  Last, gibberellin 3-oxidase converts gibberellin A20 into the active gibberellin A1.  It requires Fe2+ and L-ascorbate as cofactors."
"What is the definition of Gibberellin Biosynthesis III (Non C-3, Non C-13 Hydroxylation)?","Gibberellins (GAs) are a large class of tetracyclic diterpenoid plant hormones that regulate numerous growth and developmental processes, such as seed germination, organ elongation, and flowering induction. All known gibberellins share an ent-gibberellane skeleton and follow the same synthesis pathway. Biosynthesis begins in the plasmids via the terpenoid pathway and finishes in the endoplasmic reticulum and cytosol where they undergo modification until a biologically-active form is reached (GA1, GA3, GA4, or GA7). Gibberellins are named in the order that they are discovered (GA1 through GAn). Gibberellin biosynthesis via non C-3, non C-13 hydroxylation occurs in the cytosol and converts the inactive GA12 to the active GA4, and inactive GA36 and GA13.  The first two reactions are catalyzed by gibberellin 20-oxidase, requiring Fe2+ and L-ascorbate as cofactors.  It first converts gibberellin A12 into gibberellin A15 and then into gibberellin A24.  Gibberellin A24 has three different fates. The first route involves the conversion of gibberellin A24 into gibberellin A9 by gibberellin 20-oxidase and then the subsequent conversion of gibberellin A9 into the active gibberellin A4 by gibberellin 3-oxidase.  It requires Fe2+ and L-ascorbate as cofactors. The second route involves the conversion of gibberellin A24 into gibberellin A36 by gibberellin 3-oxidase.  The third route involves the conversion of gibberellin A24 into gibberellin A25 by gibberellin 20-oxidase and then the subsequent conversion of gibberellin A25 into gibberellin A13 by a not yet elucidated gibberellin oxidase (coloured orange in the image)."
What is the definition of Phenolic Malonylglucosides Biosynthesis?,"Naphthols, harmful phenolic foreign compounds encountered by plants in the soil, must be modified to lower their toxicity.  A yet unelucidated phenol beta-glucosyltransferase (coloured orange in the image) in Arabidopsis thaliana glucosylates napthtols (e.g. 2-naphthol into 2-naphthol glucoside, 1-naphthol into 1-naphthol glucoside).  Glucosylation may then be followed by malonylation catalyzed by phenolic glucoside malonyltransferase ( e.g. 4-methylumbelliferyl glucoside into 4-methylumbelliferone 6'-O-malonylglucoside, 2-naphthol glucoside into 2-naphthol 6'-O-malonylglucoside, and 1-naphthol glucoside into 1-naphthol 6'-O-malonylglucoside).  Unlike the excreted glucosides, the malonylated compounds are retained within vacuoles."
What is the definition of Pyrimidine Deoxyribonucleosides Salvage?,"The cytosolic salvage of precursors used to synthesize pyrimidine deoxyribonucleotides from the environment is an important alternative to the energetically expensive de novo synthesis pathway.  Since the negative charge of the deoxyribonucleotide phosphate groups prevents their import into the cell, salvage is restricted to deoxyribonucleosides which are transported into the cell via facilitated diffusion by a nucleoside carrier protein.  Following uptake into the cell, the deoxyribonucleosides are phosphorylated.  Phosphorylation imparts negative charges to the compounds, effectively trapping them within the cell.  After transport into the cell, 2'-deoxycytidine has two fates.  The first route starts with the conversion of 2'-deoxycytidine into dCMP by deoxynucleoside kinase.  This is followed by the conversion of dCMP into dCDP by UMP/CMP kinase, requiring a magnesium ion cofactor, and then the conversion of dCDP into dCTP by nucleoside-diphosphate kinase, requiring a magnesium ion cofactor.  The second route starts with the conversion of 2'-deoxycytidine into 2'-deoxyuridine by cytidine deaminase, requiring a zinc ion cofactor.  This is followed by the conversion of 2'-deoxyuridine into dUMP by thymidine kinase, and then the conversion of dUMP into dTMP by dihydrofolate reductase-thymidylate synthase.  Alternatively, dTMP can be synthesized by thymidine kinase using thymidine transported into the cell by a nucleoside carrier protein.  Next, thymidylate kinase converts dTMP into dTDP, and then nucleoside-diphosphate kinase, requiring a magnesium ion cofactor, converts dTDP into dTTP."
What is the definition of Photosynthesis?,"Photosynthesis involves the transfer and harvesting of energy from sunlight and the fixation of carbon dioxide into carbohydrates. This process occurs in higher plants, including Arabidopsis thaliana. Oxygenic photosynthesis requires water, which acts as an electron donor molecule. The reactions which involve the trapping of sunlight are known as ""light reactions"", and result in the production of NADPH, adenosine triphosphate, and molecular oxygen. The ""dark reactions"" are known as the Calvin cycle, and involve the use of the products of the light reactions to fix carbon dioxide and produce carbohydrates.  Photosynthesis begins with photosystem II, located in the thylakoid membrane within chloroplasts, which captures light energy to transfer electrons from water to plastoquinone.  This process generates oxygen as well as a proton gradient used to synthesize ATP.  The D1/D2 (psbA/psbD) reaction center heterodimer binds P680, the primary electron donor of PSII as well as several subsequent electron acceptors.  Next, the cytochrome b6-f complex mediates electron transfer between photosystem II (PSII) and photosystem I (PSI).  Plastoquinol shuttles electrons from PSII to cytochrome b6-f complex.  Plastocyanin shuttles electrons from cytochrome b6-f complex to PSI.  Photosystem I is a plastocyanin-ferredoxin oxidoreductase which uses light energy to transfer an electron from the donor P700 chlorophyll pair to the electron acceptors A0, A1, FX, FA and FB in turn. The function of PSI is to produce the NADPH necessary for the reduction of CO2 in the Calvin-Benson cycle.  Finally, the proton gradient allows ATPase to synthesize ATP from ADP.  The light-independent Calvin-Benson cycle consist of nine reactions that take place in the chloroplast stroma.  Beginning with the enzyme RuBisCO, D-ribulose-1,5-bisphosphate is converted into 3-phosphoglyceric acid.  It requires magnesium ion as a cofactor.  Next, chloroplastic glyceraldehyde 3-phosphate dehydrogenase catalyzes the conversion of glyceric acid 1,3-biphosphate into D-glyceraldehyde 3-phosphate.  Then triose-phosphate isomerase catalyzes the conversion of D-glyceraldehyde 3-phosphate into dihydroxyacetone phosphate.  Next, the enzyme fructose-bisphosphate aldolase catalyzes the conversion of dihydroxyacetone phosphate into fructose 1,6-bisphosphate.  Then fructose-1,6-bisphosphatase catalyzes the conversion of  fructose 1,6-bisphosphate into fructose-6-phosphate. It requires magnesium ion as a cofactor.  Next, transketolase catalyzes the conversion of fructose-6-phosphate into xylulose 5-phosphate.  It requires a divalent metal cation and thiamine diphosphate as cofactors.  Then the enzyme ribulose-phosphate 3-epimerase is catalyzes the interconverson of xylulose 5-phosphate and D-ribulose 5-phosphate.  Lastly, phosphoribulokinase catalyzes the conversion of D-ribulose 5-phosphate to regenerate D-ribulose-1,5-bisphosphate.  An alternative pathway intersects the Calvin-Benson cycle providing another route to synthesize D-ribulose 5-phosphate and D-xylulose 5-phosphate, which both feed back into the main cycle, from dihydroxyacetone phosphate.  This subpathway begins with the predicted enzyme sedoheptulose-1,7-bisphosphate aldolase theorized to catalyze the converson of glycerone phosphate and D-erythrose 4-phosphate into sedoheptulose-1,7-bisphosphate.  Next, sedoheptulose-1,7-bisphosphatase catalyzes the conversion of sedoheptulose-1,7-bisphosphate into D-sedoheptulose 7-phosphate.  Next, transketolase catalyzes the converson of D-sedoheptulose 7-phosphate into D-ribose 5-phosphate and D-xylulose 5-phosphate (which feeds back into the main cycle).  Lastly, ribose-5-phosphate isomerase is the probable enzyme that catalyzes the interconverson of D-ribose 5-phosphate and D-ribulose 5-phosphate.  D-ribulose 5-phosphate feeds back into the main cycle."
What is the definition of Oxidative Phosphorylation?,"Oxidative phosphorylation is the concluding pathway in cellular respiration, the series of metabolic processes that convert chemical energy from glucose into adenosine triphosphate (ATP), a usable form of energy for the cell. A series of five protein complexes, each with increasing reduction potentials, located in the mitochondrial inner membrane forms the electron transport chain (ETC). Electrons are transferred from one complex to the next in a series of redox reactions which release energy used to pump protons from the mitochondrial matrix into the intermembrane space. As a result, an electrochemical gradient forms across the inner mitochondrial membrane. Complex V (ATP synthase) is the singular channel by which protons flow back into the matrix. ATP synthase uses this gradient to synthesize ATP from ADP and phosphate (Pi). Complex I is the NADH dehydrogenase complex responsible for the oxidation of NADH and the reduction of ubiquinone (coenzyme Q), transferring two electrons from NADH to the respiratory chain. Four protons are pumped into the intermembrane space as a result of this electron transfer, and a further two protons are pumped due to the reduction of ubiquinone to ubiquinol. Complex II is the succinate dehydrogenase complex responsible for the oxidation of succinate into fumarate and the reduction of ubiquinone, transferring two electrons from succinate to ubiquinone instead of directly to the ETC. No protons are pumped at this complex because succinate oxidation releases less energy than NADH oxidation. Complex III is the ubiquinol-cytochrome c oxidoreductase complex responsible for transferring electrons from ubiquinol to cytochrome c.  Two protons are pumped into the intermembrane space as a result of the oxidization of one molecule of ubiquinol (a coenzyme that can carry two electrons) and the reduction of two molecules of cytochrome c (a heme protein that can carry only one electron). Complex IV is the cytochrome c oxidase complex responsible for transferring electrons to oxygen, the terminal electron acceptor, and reducing it to water. Four protons are pumped into the intermembrane space as a result of the electron transfer. In addition, the reduction of oxygen further contributes to the proton gradient due to its use of matrix protons. Complex V is the mitochondrial membrane F-Type ATP synthase which produces ATP from ADP in the presence of a proton gradient across the membrane (generated by electron transport complexes of the respiratory chain). An F-Type ATPase is composed of two domains: a catalytic core (where ATP is synthesized) and a proton channel."
What is the definition of Photosynthesis (Light-Dependent Reactions)?,"Photosynthesis involves the transfer and harvesting of energy from sunlight and the fixation of carbon dioxide into carbohydrates. This process occurs in higher plants, including Arabidopsis thaliana. Oxygenic photosynthesis requires water, which acts as an electron donor molecule. The reactions which involve the trapping of sunlight are known as ""light reactions"", and result in the production of NADPH, adenosine triphosphate, and molecular oxygen. The ""dark reactions"" are known as the Calvin cycle, and involve the use of the products of the light reactions to fix carbon dioxide and produce carbohydrates. The light-dependent reactions of photosynthesis begins with photosystem II, located in the thylakoid membrane within chloroplasts, which captures light energy to transfer electrons from water to plastoquinone. This process generates oxygen as well as a proton gradient used to synthesize ATP. The D1/D2 (psbA/psbD) reaction center heterodimer binds P680, the primary electron donor of PSII as well as several subsequent electron acceptors. Next, the cytochrome b6-f complex mediates electron transfer between photosystem II (PSII) and photosystem I (PSI). Plastoquinol shuttles electrons from PSII to cytochrome b6-f complex. Plastocyanin shuttles electrons from cytochrome b6-f complex to PSI. Photosystem I is a plastocyanin-ferredoxin oxidoreductase which uses light energy to transfer an electron from the donor P700 chlorophyll pair to the electron acceptors A0, A1, FX, FA and FB in turn. The function of PSI is to produce the NADPH necessary for the reduction of CO2 in the Calvin-Benson cycle. Finally, the proton gradient allows ATPase to synthesize ATP from ADP. "
What is the definition of Calvin-Benson Cycle?,"Photosynthesis involves the transfer and harvesting of energy from sunlight and the fixation of carbon dioxide into carbohydrates. This process occurs in higher plants, including Arabidopsis thaliana. Oxygenic photosynthesis requires water, which acts as an electron donor molecule. The reactions which involve the trapping of sunlight are known as ""light reactions"", and result in the production of NADPH, adenosine triphosphate, and molecular oxygen. The ""dark reactions"" are known as the Calvin cycle, and involve the use of the products of the light reactions to fix carbon dioxide and produce carbohydrates.  The light-independent Calvin-Benson cycle consist of nine reactions that take place in the chloroplast stroma. Beginning with the enzyme RuBisCO, D-ribulose-1,5-bisphosphate is converted into 3-phosphoglyceric acid. It requires magnesium ion as a cofactor. Next, chloroplastic glyceraldehyde 3-phosphate dehydrogenase catalyzes the conversion of glyceric acid 1,3-biphosphate into D-glyceraldehyde 3-phosphate. Then triose-phosphate isomerase catalyzes the conversion of D-glyceraldehyde 3-phosphate into dihydroxyacetone phosphate. Next, the enzyme fructose-bisphosphate aldolase catalyzes the conversion of dihydroxyacetone phosphate into fructose 1,6-bisphosphate. Then fructose-1,6-bisphosphatase catalyzes the conversion of fructose 1,6-bisphosphate into fructose-6-phosphate. It requires magnesium ion as a cofactor. Next, transketolase catalyzes the conversion of fructose-6-phosphate into xylulose 5-phosphate. It requires a divalent metal cation and thiamine diphosphate as cofactors. Then the enzyme ribulose-phosphate 3-epimerase is catalyzes the interconverson of xylulose 5-phosphate and D-ribulose 5-phosphate. Lastly, phosphoribulokinase catalyzes the conversion of D-ribulose 5-phosphate to regenerate D-ribulose-1,5-bisphosphate. An alternative pathway intersects the Calvin-Benson cycle providing another route to synthesize D-ribulose 5-phosphate and D-xylulose 5-phosphate, which both feed back into the main cycle, from dihydroxyacetone phosphate. This subpathway begins with the predicted enzyme sedoheptulose-1,7-bisphosphate aldolase theorized to catalyze the converson of glycerone phosphate and D-erythrose 4-phosphate into sedoheptulose-1,7-bisphosphate. Next, sedoheptulose-1,7-bisphosphatase catalyzes the conversion of sedoheptulose-1,7-bisphosphate into D-sedoheptulose 7-phosphate. Next, transketolase catalyzes the converson of D-sedoheptulose 7-phosphate into D-ribose 5-phosphate and D-xylulose 5-phosphate (which feeds back into the main cycle). Lastly, ribose-5-phosphate isomerase is the probable enzyme that catalyzes the interconverson of D-ribose 5-phosphate and D-ribulose 5-phosphate. D-ribulose 5-phosphate feeds back into the main cycle."
What is the definition of C5-Branched Dibasic Acid Metabolism?,"A dibasic acid is an acid that has two hydrogen cations to donate to a base in an acid-base reaction (Wikipedia).  C5-branched dibasic acid metabolism takes place in the chloroplast stroma.  Pyruvate from glycolysis is converted into (S)-2-Acetolactate by acetolactate synthase.  A yet non-elucidated enzyme converts pyruvate into (R)-citramalate.  The next two reactions are catalyzed by the same enzyme.  First, isopropylmalate isomerase converts (R)-citramalate into citraconic acid and then it converts citraconic acid into D-erythro-3-methylmalate.  Last, the reaction that converts D-erythro-3-methylmalate into 2-ketobutyric acid is catalyzed by the enzyme 3-isopropylmalate dehydrogenase. "
What is the definition of Pentose Phosphate Pathway?,"Pentose phosphate pathway is a metabolic pathway that takes place in cytosol in most organisms, and in plastids in plants. Pentose phosphate pathway generates pentoses, ribose 5-phosphate, NADPH and erythrose 4-phosphate. Ribose 5-phosphate is required for synthesis of nucleic acids and nucleotides. Erythrose 4-phosphate is required for synthesis of aromatic amino acids. Glycolysis is also a part of pentose phosphate pathway. The first phase of the pathway is the oxidative phase, which generates NADPH; and second phase is non-oxidative phase, which is synthesis of 5-carbon sugers (pentoses). First, glucose-6-phosphate dehydrogenase catalyzes the conversion of beta-D-glucose 6-phosphate into 6-phosphonoglucono-D-lactone, reducing NADP to NADPH in the process. Second, 6-phosphogluconolactonase catalyzes the conversion of 6-phosphonoglucono-D-lactone into 6-phospho-D-gluconate. Third, 6-phosphogluconate dehydrogenase catalyzes the conversion of 6-phospho-D-gluconate into D-ribulose 5-phosphate, reducing NADP to NADPH in the process and finishing the oxidative phase of the pathway. Next, ribulose-phosphate 3-epimerase catalyzes the interconversion of D-ribulose 5-phosphate and D-xylulose 5-phosphate, requiring a divalent metal cation as a cofactor. Ribose-5-phosphate isomerase catalyzes the interconversion of D-ribose 5-phosphate and D-ribulose 5-phosphate. Transketolase catalyzes two different reactions: glyceraldehyde-3-phosphate and either fructose-6-phosphate or sedoheptulose-7-phosphate is interconverted into xylulose 5-phosphate and either erythrose-4-phosphate or ribose-5-phosphate respectively. It requires a divalent metal cation and thiamine diphosphate as cofactors. Transaldolase catalyzes the interconversion of D-sedoheptulose 7-phosphate and D-glyceraldehyde 3-phosphate into D-erythrose 4-phosphate and beta-D-fructose 6-phosphate. Xylulose 5-phosphate/phosphate translocator preferentially transports xylulose 5-phosphate (but will also transport ribulose 5-phosphate) from the cytosol and into the chloroplast in exchange for phosphate. Xylulose 5-phosphate supplies the plastidic pentose phosphate pathway with intermediates, especially when under high demand."
What is the definition of Mannose Metabolism?,"Mannose is a sugar monomer of the aldohexose series of carbohydrates and is a C-2 epimer of glucose.  It is a key monosaccharide for protein and lipid glycosylation (Wikipedia).  The majority of mannose metabolism takes place in the cytosol.  There are two routes to form mannose 6-phosphate.  The first subpathway involves using beta-D-fructose 6-phosphate from glycolysis. The enzyme mannose-6-phosphate isomerase catalyzes the interconversion of beta-D-fructose 6-phosphate and D-mannose 6-phosphate. It requires a zinc ion as a cofactor.  The second subpathway involves using the secreted enzyme, mannan endo-1,4-beta-mannosidase to catalyze the random hydrolysis of (1->4)-beta-D-mannosidic linkages in mannans to form D-mannose residues.  These D-mannose residues are then imported into the cell cytoplasm via a sugar transport protein (a sugar/hydrogen symporter).  Once inside the cell, hexokinase catalyzes the conversion of D-mannose into D-mannose 6-phosphate.  Next, phosphomannomutase catalyzes the interconversion of D-mannose 6-phosphate and D-mannose 1-phosphate.  However, D-mannose 1-phosphate can also be synthesized from ADP-mannose in the chloroplast via nudix hydrolase 14 and a magnesium or manganese ion cofactor.  D-mannose 1-phosphate is then transported into the cytosol by a predicted D-mannose 1-phosphate transporter.  Next, mannose-1-phosphate guanylyltransferase uses GTP to catalyze the conversion of D-mannose 1-phosphate into GDP-mannose.  This is followed by GDP-mannose 4,6 dehydratase catalyzing the conversion of GDP-mannose into GDP-4-dehydro-6-deoxy-D-mannose.  It requires NADP as a cofactor.  Last, GDP-L-fucose synthase catalyzes the conversion of GDP-4-dehydro-6-deoxy-D-mannose into GDP-L-fucose. "
What is the definition of Fructose Metabolism?,"Fructose metabolism takes place in the cytosol.  D-Fructose can be synthesized from either isomerization of alpha-D-glucose via xylose isomerase or from sorbitol via sorbitol dehydrogenase.  D-Fructose can then be directed to either Amino Sugar and Nucleotide Sugar Metabolism or used to synthesize beta-D-fructose 6-phosphate, either by hexokinase or fructokinase.  Beta-D-fructose 6-phosphate can also be synthesized from D-fructose 2,6-bisphosphate via the enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase.  Next, 6-phosphofructokinase uses ATP to catalyze the phosphorylation of D-fructose 6-phosphate to fructose 1,6-bisphosphate.  It requires a magnesium ion as a cofactor.  Alternatively, fructose 1,6-bisophosphate can be synthesized from beta-D-fructose 6-phosphate from pyrophosphate--fructose 6-phosphate 1-phosphotransferase.  This enzyme has a regulatory alpha subunit and a catalytic beta subunit and requires magnesium ion as a cofactor.  Fructose 1,6-bisophosphate can be re-synthesized into beta-D-fructose 6-phosphate by fructose-1,6-bisphosphatase.  Next, fructose-bisphosphate aldolase catalyzes the conversion of beta-D-fructose 1,6-bisphosphate into D-glyceraldehyde 3-phosphate and glycerone phosphate.  Triosephosphate isomerase can also catalyze the interconversion of D-glyceraldehyde 3-phosphate and glycerone phosphate.  Fructose-bisphosphate aldolase also catalyzes the reversible conversion of D-fructose 1-phosphate into glycerone phosphate and D-glyceraldehyde.  D-glyceraldehyde is theorized to be then be subsequently converted into D-glyceraldehyde 3-phosphate via the predicted protein triokinase (coloured in orange in the image)."
What is the definition of Ascorbate Metabolism?,"Vitamin C (ascorbate) is a vitamin found in food and used as a dietary supplement.  The vast majority of animals and plants are able to synthesize vitamin C, through a sequence of enzyme-driven steps, which convert monosaccharides to vitamin C. In plants, this is accomplished through the conversion of mannose or galactose to ascorbic acid starting in the cytosol and ending in the mitochondrial matrix (Wikipedia).  First, GDP-mannose 3,5-epimerase catalyzes the reversible epimerization of GDP-D-mannose into either GDP-L-gulose or GDP-L-galactose.  It also can reversibly epimerize GDP-L-gulose into GDP-L-galactose and vice versa.  It requires NAD as a cofactor.  Second, GDP-L-galactose phosphorylase catalyzes the conversion of GDP-L-galactose into L-galactose 1-phosphate.  Third, L-galactose 1-phosphate phosphatase catalyzes the conversion of L-galactose 1-phosphate into L-galactose.  It requires magnesium ion as a cofactor.  Fourth, L-galactose dehydrogenase catalyzes the conversion of L-galactose into L-galactono-1,4-lactone.  L-galactono-1,4-lactone must then be imported into the mitochondrial matrix by a predicted innermitochondrial membrane transporter to complete ascorbate synthesis.  L-galactono-1,4-lactone dehydrogenase, localized to the innermitochondrial membrane (coloured dark green in the image), catalyzes two reactions in ascorbate metabolism: the conversion of L-galactono-1,4-lactone into L-ascorbate and the subsequent conversion of L-ascorbate into L-dehydroascorbate. It requires FAD as a cofactor.  Ascorbate can then be converted into monodehydroascorbate radical by the mitochondrial L-ascorbate peroxidase S (this plays a key role in hydrogen peroxide removal).  Monodehydroascorbate reductase 5 then can convert monodehydroascorbate radical back into L-ascorbate."
What is the definition of Butanoate Metabolism?,"Butanoate or butyrate is the traditional name for the conjugate base of butanoic acid (also known as butyric acid).  Butanoate metabolism includes L-glutamate degradation into the signal molecule GABA followed by subsequent reactions to make further products.  Glutamate decarboxylase is an enzyme in the cytosol that catalyzes the conversion of L-glutamate into 4-aminobutanoate (GABA). It requires pyridoxal 5'-phosphate as a cofactor.  This is followed by GABA permease, belonging to the APC Family of transport proteins, transporting GABA from the cytosol into the mitochondria matrix.  Next, gamma-aminobutyrate transaminase degrades gamma-amino butyric acid (GABA) into succinate semialdehyde and uses either pyruvate or glyoxylate as an amino-group acceptor. The pyruvate-dependent activity is reversible while the glyoxylate-dependent activity is irreversible.  Afterwards, succinate-semialdehyde dehydrogenase oxidizes succinate semialdehyde into succinate.  A predicted succinate semialdehyde transporter in the mitochondria inner membrane is theorized to export succinate semialdehyde from the mitochondrial matrix into the cytosol.  There, glyoxylate/succinic semialdehyde reductase catalyzes the reversible conversion of succinate semialdehyde into 4-hydroxybutanoate.  Butanoate metabolism in Arabidopsis thaliana also includes reactions involving acetyl-CoA and acetoacetyl-CoA.  3-hydroxybutyryl-CoA dehydrogenase is a predicted enzyme (coloured orange in the image) in the cytosol that is theorized to catalyze the reversible conversion of 3-hydroxybutanoyl-CoA into acetoacetyl-CoA.  Acetyl-CoA acetyltransferase then catalyzes the reversible conversion of acetoacetyl-CoA into acetyl-CoA.  Then, hydroxymethylglutaryl-CoA synthase condenses acetyl-CoA with acetoacetyl-CoA to form 3-hydroxy-3-methylglutaryl-CoA.  This is followed by a predicted 3-hydroxy-3-methylglutaryl-CoA transporter localized to the mitochondria inner membrane that is theorized to import 3-hydroxy-3-methylglutaryl-CoA into the mitochondrial matrix from the cytosol.  Once there, hydroxymethylglutaryl-CoA lyase catalyzes the synthesis of acetoacetate and acetyl-CoA from 3-hydroxy-3-methylglutaryl-CoA."
What is the definition of Triacylglycerol Degradation TG(16:0/16:0/16:0)?,"In higher plants, the primary seed storage reserve is triacylglycerol rather than carbohydrates. Thus, triacylglycerol degradation is an important pathway from which plants obtain energy for growth. First, triacylglycerol lipase, an enzyme localized to the oil body (storage vacuole) membrane, catalyzes the conversion of a triglyceride into a 1,2-diglyceride. Second, the predicted enzyme diglyceride lipase (coloured orange in the image) is theorized to catalyze the conversion of a 1,2-diglyceride iinto a 2-acylglycerol. Third, a 2-acylglycerol is spontaneously converted into a 1-monoglyceride. Fourth, acylhydrolase catalyzes the conversion of a 1-monoglyceride into glycerol. Fifth, glycerol kinase catalyzes the conversion of glycerol into glycerol 3-phosphate. Sixth, glycerol-3-phosphate dehydrogenase (coloured dark green in the image), localized to the mitochondrial inner membrane, catalyzes the conversion of glycerol 3-phosphate into glycerone phosphate."
What is the definition of Limonene and Pinene Degradation?,"Both enzymes involved with the known reactions for limonene and pinene degradation in Arabidopsis thaliana are membrane-localized (e.g. endoplasmic reticulum membrane).  The first enzyme, an aldehyde dehydrogenase (NAD+), catalyzes the conversion of perillyl aldehyde into perillic acid.  The second enzyme, a cytochrome P450 protein, catalyzes the conversions of alpha-pinene to myrtenol and to pinocarveol, thus exhibiting both alpha-pinene dehydrogenase and alpha-pinene monooxygenase activity."
What is the definition of Monoterpenoid Biosynthesis?,"Monoterpenoids are kind of volatile oils, which are derived from geranyl diphosphate (Geranyl-PP/GPP) that are also consisted of two isoprene units. In Arabidopsis thaliana, most reactions in monoterpenoid biosynthesis take place in the chloroplast and require either magnesium or manganese ions as cofactors. S-(+)-linalool synthase catalyzes the conversion of geranyl diphosphate into (+)-linalool. Two different enzymes can function as myrcene synthases and catalyze the conversion of geranyl diphosphate into myrcene: tricyclene synthase and beta-myrcene/(E)-beta-ocimene synthase 2. 1,8-cineole synthase catalyzes two successive reactions in monoterpenoid biosynthesis: the conversion of geranyl diphosphate into alpha-terpineol and the conversion of alpha-terpineol into eucalyptol (1,8-cineole). It also catalyzes four other conversions, all of geranyl diphosphate, into (-)-beta-pinene, (-)-alpha-pinene, sabinene and terpinolene, all with varying frequency. Additionally, (E,E)-alpha-farnesene synthase, an enzyme used in the conversion of farnesyl diphosphate to isomers of farnesene, can additionally catalyze the conversion of geranyl diphosphate into trans-ocimen. Finally, the beta-myrcene/(E)-beta-omicine synthase 2 enzyme can also work to catalyze the conversion of geranyl diphosphate into (-)-limonene. Distinct from the other enzymes listed, (+)-Neomenthol dehydrogenase is an enzyme found in the cytosol that catalyzes the conversion of (-)-menthone into (+)-neomenthol."
What is the definition of Phosphatidylcholine Biosynthesis?,"Phosphatidylcholines (PC) are a class of phospholipids that incorporate a phosphocholine headgroup into a diacylglycerol backbone.  They are the most abundant phospholipid in eukaryotic cell membranes and has both structural and signalling roles.  In eukaryotes, there exist two phosphatidylcholine biosynthesis pathways: the Kennedy pathway and the methylation pathway.  The Kennedy pathway begins with the direct phosphorylation of free choline into phosphocholine followed by conversion into CDP-choline and subsequently phosphatidylcholine.  It is the major synthesis route in animals.  The methylation pathway involves the 3 successive methylations of phosphoethanolamine to form phosphocholine which is then funnelled into the Kennedy pathway to make phosphatidylcholine.  In plants, phosphatidylcholine biosynthesis is implemented using a mix between the two pathways.  An alternative of the methylation pathway uses phosphatidylethanolamine as a starting compound, but no enzyme has been found in Arabidopsis to catalyze the first methylation to form phosphatidyl-N-methylethanolamine.  Many enzymes involved in this pathway are localized to the cell membrane but are not drawn as such for clarity.  Instead, they are indicated with a dark green colour and appear to be free floating in the cytosol.  The first reaction of the Kennedy pathway involves the membrane-localized enzyme choline/ethanolamine kinase catalyzing the conversion of choline into phosphocholine.  Second, choline-phosphate cytidylyltransferase catalyzes the conversion of phosphocholine to CDP-choline.  Last, choline/ethanolaminephosphotransferase, localized to the cell membrane, catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors.  Note that phosphatidylcholine can be converted to either phosphocholine by a non-specific phospholipase or converted to choline by phospholipase D.  Phosphocholine can also be converted to choline via phosphoethanolamine/phosphocholine phosphatase.  The methylation pathway begins with serine decarboxylase catalyzing the biosynthesis of ethanolamine from serine.  It requires pyridoxal 5'-phosphate as a cofactor.  Next, choline/ethanolamine kinase, localized to the cell membrane, catalyzes the conversion of ethanolamine to phosphoethanolamine.  Phosphoethanolamine N-methyltransferase (PEAMT), located in the cytosol, then catalyzes three sequential N-methylation steps to convert phosphoethanolamine to phosphocholine.  PEAMT uses S-adenosyl-L-methionine as a methyl donor.  Phosphocholine then enters the Kennedy pathway.  Alternatively, in a subpathway parallel to the Kennedy pathway, phosphoethanolamine can be converted into phosphatidylethanolamine.  Phosphatidylethanolamine is also synthesized from phosphatidylserine in the endoplasmic reticulum by phosphatidylserine decarboxylase.  Note that phosphatidylethanolamine can be converted to either phosphoethanolamine by a non-specific phospholipase or converted to ethanolamine by phospholipase D.  The two methylated intermediates N-methylethanolamine phosphate and N-dimethylethanolamine phosphate can also undergo reactions parallel to the Kennedy pathway to form the methylated intermediates of phosphatidylethanolamine (otherwise catalyzed by phosphatidyl-N-methylethanolamine N-methyltransferase, localized to the endoplasmic reticulum membrane, to form phosphatidylcholine)."
What is the definition of Phosphatidylethanolamine Biosynthesis?,"Phosphatidylethanolamines (PE) are the second most abundant phospholipid in eukaryotic cell membranes, and contrary to phosphatidylcholine, it is concentrated with phosphatidylserine in the cell membrane's inner leaflet.  In Arabidopsis thaliana, there exist two phosphatidylethanolamine biosynthesis pathways.  The first pathway consists of mainly enzymes localized to either the cytosol or the cell membrane. Cell membrane-localized enzymes in this pathway are not drawn as such for clarity.  Instead, they are indicated with a dark green colour and appear to be free floating in the cytosol.  This first pathway begins with serine decarboxylase catalyzing the biosynthesis of ethanolamine from serine. It requires pyridoxal 5'-phosphate as a cofactor. Next, choline/ethanolamine kinase, localized to the cell membrane, catalyzes the conversion of ethanolamine to phosphoethanolamine.  Then ethanolamine-phosphate cytidylyltransferase, localized to the mitochondria outer membrane, catalyzes the conversion of phosphoethanolamine to CDP-ethanolamine.  Last, choline/ethanolaminephosphotransferase, localized to the cell membrane, catalyzes phosphatidylethanolamine CDP-ethanolamine, respectively.  The second pathway consists of mainly enzymes localized to the endoplasmic reticulum membrane (also depicted in dark green in the image.  Beginning in the cytosol, glycerol-3-phosphate dehydrogenase [NAD(+)] catalyzes the interconversion of glycerone phosphate (from glycolysis) and glycerol 3-phosphate.  After glycerol 3-phosphate enters the endoplasmic reticulum, glycerol-3-phosphate acyltransferase esterifies the acyl-group from acyl-CoA to the sn-1 position of glycerol-3-phosphate.  Third, 1-acyl-sn-glycerol-3-phosphate acyltransferase 2 catalyzes the conversion of lysophosphatidic acid (LPA or 1-acyl-sn-glycerol 3-phosphate) into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by incorporating an acyl moiety at the 2nd position.  Fourth, phosphatidate cytidylyltransferase catalyzes the conversion of a 1,2-diacyl-sn-glycerol 3-phosphate into a CDP-diacylglycerol.  It requires a magnesium ion as a cofactor.  Fifth, CDP-diacylglycerol--serine O-phosphatidyltransferase catalyzes the synthesis of phosphatidylserine from L-serine and a CDP-diacylglycerol.  Last, phosphatidylserine decarboxylase catalyzes the formation of phosphatidylethanolamine from phosphatidylserine. It requires pyruvate as a cofactor."
What is the definition of Phosphatidylcholine Biosynthesis?,"Phosphatidylcholines (PC) are a class of phospholipids that incorporate a phosphocholine headgroup into a diacylglycerol backbone. They are the most abundant phospholipid in eukaryotic cell membranes and has both structural and signalling roles. In eukaryotes, there exist two phosphatidylcholine biosynthesis pathways: the Kennedy pathway and the methylation pathway. The Kennedy pathway begins with the direct phosphorylation of free choline into phosphocholine followed by conversion into CDP-choline and subsequently phosphatidylcholine. It is the major synthesis route in animals. The methylation pathway involves the 3 successive methylations of phosphatidylethanolamine to form phosphatidylcholine.  The first reaction of the Kennedy pathway involves the cytosol-localized enzyme choline/ethanolamine kinase catalyzing the conversion of choline into phosphocholine. Second, choline-phosphate cytidylyltransferase, localized to the endoplasmic reticulum membrane, catalyzes the conversion of phosphocholine to CDP-choline. Last, choline/ethanolaminephosphotransferase catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors.  A parallel Kennedy pathway forms phosphatidylethanolamine from ethanolamine - the only difference being a different enzyme, ethanolamine-phosphate cytidylyltransferase, catalyzing the second step.   Phosphatidylethanolamine is also synthesized from phosphatidylserine in the mitochondrial membrane by phosphatidylserine decarboxylase.  Phosphatidylethanolamine funnels into the methylation pathway in which phosphatidylethanolamine N-methyltransferase (PEMT) then catalyzes three sequential N-methylation steps to convert phosphatidylethanolamine to phosphatidylcholine. PEMT uses S-adenosyl-L-methionine as a methyl donor."
What is the definition of Phosphatidylcholine Biosynthesis PC(14:0/14:0)?,"Phosphatidylcholines (PC) are a class of phospholipids that incorporate a phosphocholine headgroup into a diacylglycerol backbone. They are the most abundant phospholipid in eukaryotic cell membranes and has both structural and signalling roles. In eukaryotes, there exist two phosphatidylcholine biosynthesis pathways: the Kennedy pathway and the methylation pathway. The Kennedy pathway begins with the direct phosphorylation of free choline into phosphocholine followed by conversion into CDP-choline and subsequently phosphatidylcholine. It is the major synthesis route in animals. The methylation pathway involves the 3 successive methylations of phosphatidylethanolamine to form phosphatidylcholine. The first reaction of the Kennedy pathway involves the cytosol-localized enzyme choline/ethanolamine kinase catalyzing the conversion of choline into phosphocholine. Second, choline-phosphate cytidylyltransferase, localized to the endoplasmic reticulum membrane, catalyzes the conversion of phosphocholine to CDP-choline. Last, choline/ethanolaminephosphotransferase catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors. A parallel Kennedy pathway forms phosphatidylethanolamine from ethanolamine - the only difference being a different enzyme, ethanolamine-phosphate cytidylyltransferase, catalyzing the second step. Phosphatidylethanolamine is also synthesized from phosphatidylserine in the mitochondrial membrane by phosphatidylserine decarboxylase. Phosphatidylethanolamine funnels into the methylation pathway in which phosphatidylethanolamine N-methyltransferase (PEMT) then catalyzes three sequential N-methylation steps to convert phosphatidylethanolamine to phosphatidylcholine. PEMT uses S-adenosyl-L-methionine as a methyl donor."
What is the definition of Phosphatidylethanolamine Biosynthesis PE(14:0/14:0)?,"Phosphatidylethanolamines (PE) are a class of phospholipids that incorporate a phosphoric acid headgroup into a diacylglycerol backbone. They are the second most abundant phospholipid in eukaryotic cell membranes, and contrary to phosphatidylcholine, it is concentrated with phosphatidylserine in the cell membrane's inner leaflet. In Homo sapiens, there exist two phosphatidylethanolamine biosynthesis pathways. In the visualization, all enzymes that are dark green in colour are membrane-localized. The first pathway synthesizes phosphatidylethanolamine from ethanolamine via the Kennedy pathway. First, the cytosol-localized enzyme choline/ethanolamine kinase catalyzes the conversion of choline into phosphocholine. Second, choline-phosphate cytidylyltransferase, localized to the endoplasmic reticulum membrane, catalyzes the conversion of phosphocholine to CDP-choline. Last, choline/ethanolaminephosphotransferase catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors. Phosphatidylethanolamine is also synthesized from phosphatidylserine at the mitochondrial inner membrane by phosphatidylserine decarboxylase. Phosphatidylserine, itself, is synthesized using a base-exchange reaction with phosphatidylcholine. This reaction is catalyzed by phosphatidylserine synthase which is located in the endoplasmic reticulum membrane."
What is the definition of De Novo Triacylglycerol Biosynthesis?,"A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids.  De novo biosynthesis of triglycerides is also known as the phosphatidic acid pathway, and it is mainly associated with the liver and adipose tissue.  All membrane-localized enzymes are coloured dark green in the image.  First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate.  Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA).  The next three steps are localized to the endoplasmic reticulum membrane.  The enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone.  Next, magnesium-dependent phosphatidate phosphatase catalyzes the conversion of phosphatidic acid into diacylglycerol.  Last, the enzyme diacylglycerol O-acyltransferase synthesizes triacylglycerol from diacylglycerol and a fatty acyl-CoA. "
What is the definition of De Novo Triacylglycerol Biosynthesis TG(10:0/10:0/10:0)?,"A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and other animals, as well as vegetable fat. They are also present in the blood to enable the bidirectional transference of adipose fat and blood glucose from the liver, and are a major component of human skin oils. (Wikipedia) De novo biosynthesis of triglycerides is also known as the phosphatidic acid pathway, and it is mainly associated with the liver and adipose tissue. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). The next three steps are localized to the endoplasmic reticulum membrane. The enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. Next, magnesium-dependent phosphatidate phosphatase catalyzes the conversion of phosphatidic acid into diacylglycerol. Last, the enzyme diacylglycerol O-acyltransferase synthesizes triacylglycerol from diacylglycerol and a fatty acyl-CoA."
What is the definition of Cardiolipin Biosynthesis?,"Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG."
What is the definition of Cardiolipin Biosynthesis CL(16:0/16:0/16:0/16:0)?,"Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism. (Wikipedia) Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor."
What is the definition of Phosphatidylethanolamine Biosynthesis?,"Phosphatidylethanolamines (PE) are the second most abundant phospholipid in eukaryotic cell membranes, and contrary to phosphatidylcholine, it is concentrated with phosphatidylserine in the cell membrane's inner leaflet. In Homo sapiens, there exist two phosphatidylethanolamine biosynthesis pathways. In the visualization, all enzymes that are dark green in colour are membrane-localized. The first pathway synthesizes phosphatidylethanolamine from ethanolamine via the Kennedy pathway. First, the cytosol-localized enzyme choline/ethanolamine kinase catalyzes choline to convert to phosphocholine. Second, choline-phosphate cytidylyltransferase, localized to the endoplasmic reticulum membrane, catalyzes phosphocholine to convert to CDP-choline. Last, choline/ethanolaminephosphotransferase catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors. Phosphatidylethanolamine is also synthesized from phosphatidylserine at the mitochondrial inner membrane by phosphatidylserine decarboxylase. Phosphatidylserine, itself, is synthesized using a base-exchange reaction with phosphatidylcholine. This reaction is catalyzed by phosphatidylserine synthase which is located in the endoplasmic reticulum membrane."
What is the definition of Androstenedione Metabolism?,"Androstenedione is an endogenous weak androgen steroid hormone that is a precursor of testosterone and other androgens, as well as of estrogens like estrone (Wikipedia). Its metabolism occurs primarily in the endoplasmic reticulum (membrane-associated enzymes are coloured dark green in the image). Conversion of androstenedione to testosterone requires the enzyme testosterone 17-beta-dehydrogenase 3. Conversion of androstenedione to estrone involves three successive reactions catalyzed by the enzyme aromatase (cytochrome P450 19A1). Androstenedione can also be converted into etiocholanolone glucuronide, androsterone glucuronide, and adrenosterone. The three-reaction subpathway to synthesize etiocholanolone glucuronide begins with the enzyme 3-oxo-5-beta-steroid 4-dehydrogenase catalyzing the conversion of androstenedione to etiocholanedione. This is followed by the conversion of etiocholanedione to etiocholanolone which is catalyzed by aldo-keto reductase family 1 member C4. Lastly, the large membrane-associated multimer UDP-glucuronosyltransferase 1-1 catalyzes the conversion of etiocholanolone to etiocholanolone glucuronide. The three-reaction subpathway to synthesize androsterone glucuronide begins with the conversion of androstenedione to androstanedione via 3-oxo-5-alpha-steroid 4-dehydrogenase 1. Anstrostanedione is then converted into androsterone via aldo-keto reductase family 1 member C4. The last reaction to form androsterone glucuronide is catalyzed by the large multimer UDP-glucuronosyltransferase 1-1. The two-reaction subpathway to synthesize adrenosterone begins in the mitochondrial inner membrane where androstenedione is first converted into 11beta-hydroxyandrost-4-ene-3,17-dione by the enzyme cytochrome P450 11B1. Following transport to the endoplasmic reticulum, 11beta-hydroxyandrost-4-ene-3,17-dione is converted into adrenosterone via corticosteroid 11-beta-dehydrogenase isozyme 1."
What is the definition of Estrone Metabolism?,"Estrone (also known as oestrone) is a weak endogenous estrogen, a steroid and minor female sex hormone. Estrone is synthesized from cholesterol and secreted from gonads. Endoplasmic reticulum (ER) is the place that estrone undergoes primary metabolism. Estrone sulfate and estrone glucuronide are the conjugated product of estrone; and CYP450 can hydroxylate estrone into catechol estrogens. The enzyme catechol O-methyltransferase catalyzes the conversion of 2-hydroxyestrone into 2-methoxyestrone which is used to synthesize 2-methoxyestrone 3-glucuronide via the membrane-associated massive multimer UDP-glucuronosyltransferase 1-1. Estrone can also be reversibly converted into estradiol by estradiol 17-beta-dehydrogenase 1. This same enzyme can reversibly convert 16a-hydroxyestrone (synthesized from estrone via cytochrome P450 3A5) into estriol. Estriol is alternatively synthesized from estradiol via cytochrome P450 3A5."
What is the definition of BCR-ABL Action in CML Pathogenesis?,"The BCR-ABL fusion protein is a cytoplasm-targeted constitutively active tyrosine kinase that causes uninhibited cell proliferation via signalling cascades. This fusion protein is the result of a genetic abnormality known as the Philadelphia chromosome in which Abelson Murine Leukemia viral oncogene homolog 1 (ABL1) translocates within the Breakpoint Cluster Region (BCR) gene on chromosome 22. The action of BCR-ABL produces chronic myelogenous leukemia (CML), a cancer characterized by increased and unregulated growth of white blood cells in the bone marrow and the accumulation of these cells in the blood. Physiologically, ABL is a tyrosine kinase involved with cell growth that moves between the nucleus and the cytoplasm. Upon fusion with BCR, the oncoprotein is constitutively activated due to a preference for dimerization or tetramerization promoting subsequent autophosphorylation, and it is retained in the cytoplasm. BCR-ABL activates several oncogenic pathways which promote increased cell proliferation and survival including the MAPK/ERK Pathway, the JAK-STAT Pathway, and the PI3K/Akt pathway. BCR-ABL forms a complex with GRB2, GAB2, and SOS that activates Ras (converted from its inactive GDP-bound state to the active GTP-bound state). Ras signalling triggers the MAPK/ERK pathway which stimulates abnormal cell proliferation through regulation of transcription and translation. The BCR-ABL/GRB2/GAB2/SOS complex also activates STAT5 either through direct phosphorylation or indirectly through JAK2 kinase to promote survival. Additionally, JAK2 kinase activates the MYC transcription factor for growth-related genes. The PI3K/Akt pathway can be activated either via the BCR-ABL/GRB2/GAB2/SOS complex or the BCR-ABL/CRK/CRKL/CBL/PI3K complex. Akt functions in: (1) increasing cell proliferation by promoting the degradation of p27 (CDKN1B) through the upregulation of SKP2; (2) enhancing protein translation (and subsequently increasing cell proliferation) by activating mTOR kinase; (3) and preventing apoptosis to ensure survival by inhibiting both FOXO transcription factors and the protein Bcl2-associated agonist of cell death (BAD) as well as activating MDM2 which inhibits the tumour suppressor p53."
What is the definition of Imatinib Inhibition of BCR-ABL?,"Imatinib is a tyrosine kinase inhibitor used to treat cancers such as chronic myelogenous leukemia (CML), a cancer characterized by increased and unregulated growth of white blood cells in the bone marrow and the accumulation of these cells in the blood. The cause of CML pathophysiology is the BCR-ABL fusion protein - the result of a genetic abnormality known as the Philadelphia chromosome in which Abelson Murine Leukemia viral oncogene homolog 1 (ABL1) translocates within the Breakpoint Cluster Region (BCR) gene on chromosome 22. BCR-ABL is a cytoplasm-targeted constitutively active tyrosine kinase that activates several oncogenic pathways which promote increased cell proliferation and survival including the MAPK/ERK Pathway, the JAK-STAT Pathway, and the PI3K/Akt pathway. Imatinib inhibits BCR-ABL activity by binding a highly conserved ATP binding site to effectively lock the tyrosine kinase in an inactive conformation. As a result, phosphate is unable to be transferred from ATP to activate oncogenic signalling cascades. For greater detail, refer to the pathway titled BCR-ABL Action in CML Pathogenesis. Imatinib resistance in the form of BCR-ABL mutations (e.g. T315I) is an ongoing challenge. Next generation inhibitors have been developed to combat this resistance, but further research is necessary."
What is the definition of Dasatinib Inhibition of BCR-ABL?,"Dasatinib is a tyrosine kinase inhibitor used to treat chronic myelogenous leukemia (CML), a cancer characterized by increased and unregulated growth of white blood cells in the bone marrow and the accumulation of these cells in the blood. The cause of CML pathophysiology is the BCR-ABL fusion protein - the result of a genetic abnormality known as the Philadelphia chromosome in which Abelson Murine Leukemia viral oncogene homolog 1 (ABL1) translocates within the Breakpoint Cluster Region (BCR) gene on chromosome 22. BCR-ABL is a cytoplasm-targeted constitutively active tyrosine kinase that activates several oncogenic pathways which promote increased cell proliferation and survival including the MAPK/ERK Pathway, the JAK-STAT Pathway, and the PI3K/Akt pathway. Dasatinib is considered a second generation BCR-ABL inhibitor (Imatinib being the progenitor) that inhibits BCR-ABL activity by binding a highly conserved ATP binding site to effectively lock the tyrosine kinase in an inactive conformation. As a result, phosphate is unable to be transferred from ATP to activate oncogenic signalling cascades. For greater detail, refer to the pathway titled BCR-ABL Action in CML Pathogenesis. Dasatinib is able to bind ABL with greater affinity than Imatinib, partly owing to its ability to recognize multiple states of the enzyme. It is therefore administered to patients with Imatinib resistance. Notably, Dasatinib is ineffective against the T315I mutation in BCR-ABL, and further research is necessary."
What is the definition of Nilotinib Inhibition of BCR-ABL?,"Nilotinib is a tyrosine kinase inhibitor used to treat chronic myelogenous leukemia (CML), a cancer characterized by increased and unregulated growth of white blood cells in the bone marrow and the accumulation of these cells in the blood. The cause of CML pathophysiology is the BCR-ABL fusion protein - the result of a genetic abnormality known as the Philadelphia chromosome in which Abelson Murine Leukemia viral oncogene homolog 1 (ABL1) translocates within the Breakpoint Cluster Region (BCR) gene on chromosome 22. BCR-ABL is a cytoplasm-targeted constitutively active tyrosine kinase that activates several oncogenic pathways which promote increased cell proliferation and survival including the MAPK/ERK Pathway, the JAK-STAT Pathway, and the PI3K/Akt pathway. Nilotinib is considered a second generation BCR-ABL inhibitor (Imatinib being the progenitor) that inhibits BCR-ABL activity by binding a highly conserved ATP binding site to effectively lock the tyrosine kinase in an inactive conformation. As a result, phosphate is unable to be transferred from ATP to activate oncogenic signalling cascades. For greater detail, refer to the pathway titled BCR-ABL Action in CML Pathogenesis. Nilotinib is able to bind ABL with greater affinity than Imatinib (20-fold to 30-fold increase). It is therefore administered to patients with Imatinib resistance. Notably, Nilotinib is ineffective against the T315I mutation in BCR-ABL, and further research is necessary."
What is the definition of Bosutinib Inhibition of BCR-ABL?,"Bosutinib is a tyrosine kinase inhibitor used to treat chronic myelogenous leukemia (CML), a cancer characterized by increased and unregulated growth of white blood cells in the bone marrow and the accumulation of these cells in the blood. The cause of CML pathophysiology is the BCR-ABL fusion protein - the result of a genetic abnormality known as the Philadelphia chromosome in which Abelson Murine Leukemia viral oncogene homolog 1 (ABL1) translocates within the Breakpoint Cluster Region (BCR) gene on chromosome 22. BCR-ABL is a cytoplasm-targeted constitutively active tyrosine kinase that activates several oncogenic pathways which promote increased cell proliferation and survival including the MAPK/ERK Pathway, the JAK-STAT Pathway, and the PI3K/Akt pathway. Bosutinib is considered a second generation BCR-ABL inhibitor (Imatinib being the progenitor) that inhibits BCR-ABL activity by binding a highly conserved ATP binding site to effectively lock the tyrosine kinase in an inactive conformation. As a result, phosphate is unable to be transferred from ATP to activate oncogenic signalling cascades. For greater detail, refer to the pathway titled BCR-ABL Action in CML Pathogenesis. Bosutinib is able to bind ABL with greater affinity than Imatinib, perhaps due to its ability to bind both inactive and intermediate conformations of the protein. It is therefore administered to patients with Imatinib resistance. Bosutinib may have a safer toxicity profile than both Imatinib and Dasatinib because it does not significantly inhibit the receptors KIT and PDGFR. Notably, Bosutinib is ineffective against the T315I mutation in BCR-ABL, and further research is necessary."
What is the definition of Bafetinib Inhibition of BCR-ABL?,"Bafetinib is a tyrosine kinase inhibitor used to treat chronic myelogenous leukemia (CML), a cancer characterized by increased and unregulated growth of white blood cells in the bone marrow and the accumulation of these cells in the blood. The cause of CML pathophysiology is the BCR-ABL fusion protein - the result of a genetic abnormality known as the Philadelphia chromosome in which Abelson Murine Leukemia viral oncogene homolog 1 (ABL1) translocates within the Breakpoint Cluster Region (BCR) gene on chromosome 22. BCR-ABL is a cytoplasm-targeted constitutively active tyrosine kinase that activates several oncogenic pathways which promote increased cell proliferation and survival including the MAPK/ERK Pathway, the JAK-STAT Pathway, and the PI3K/Akt pathway. Bafetinib is considered a second generation BCR-ABL inhibitor (Imatinib being the progenitor) that inhibits BCR-ABL activity by binding a highly conserved ATP binding site to effectively lock the tyrosine kinase in an inactive conformation. As a result, phosphate is unable to be transferred from ATP to activate oncogenic signalling cascades. For greater detail, refer to the pathway titled BCR-ABL Action in CML Pathogenesis. Bafetinib is able to bind ABL with greater affinity than Imatinib (25-55 times more potent). It is therefore administered to patients with Imatinib resistance. Notably, Bafetinib is ineffective against the T315I mutation in BCR-ABL, and further research is necessary."
What is the definition of Ponatinib Inhibition of BCR-ABL?,"Ponatinib is a tyrosine kinase inhibitor used to treat chronic myelogenous leukemia (CML), a cancer characterized by increased and unregulated growth of white blood cells in the bone marrow and the accumulation of these cells in the blood. The cause of CML pathophysiology is the BCR-ABL fusion protein - the result of a genetic abnormality known as the Philadelphia chromosome in which Abelson Murine Leukemia viral oncogene homolog 1 (ABL1) translocates within the Breakpoint Cluster Region (BCR) gene on chromosome 22. BCR-ABL is a cytoplasm-targeted constitutively active tyrosine kinase that activates several oncogenic pathways which promote increased cell proliferation and survival including the MAPK/ERK Pathway, the JAK-STAT Pathway, and the PI3K/Akt pathway. Ponatinib is considered a third generation BCR-ABL inhibitor (Imatinib being the progenitor) due to its effectiveness against the T315I mutation in BCR-ABL. For greater detail of some of the signalling pathways inhibited by BCR-ABL inhibition, refer to the pathway titled BCR-ABL Action in CML Pathogenesis."
"What is the definition of Cardiolipin Biosynthesis CL(a-13:0/18:2(9Z,11Z)/18:2(9Z,11Z)/18:2(9Z,11Z))?","Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism. (Wikipedia) Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor. Newly synthesized cardiolipins undergo remodeling, a process carried out by the enzyme tafazzin. A mutated tafazzin gene disrupts this post-synthetic remodeling and causes Barth syndrome (BTHS), an X-linked human disease (PMID: 16973164). BTHS patients seem to lack acyl specificity and consequently, many potential cardiolipin species can exist (PMID: 16226238)."
What is the definition of Lafutidine H2-Antihistamine Action?,Lafutidine (also known as INN) is a second generation histamine H2 receptor antagonist that can be used for treating ulcers and reflux. Inhibition of histamine H2 receptor can inhibit histamine-stimulated gastric acid secretion which will lead to reduced gastric volume and acidity.
What is the definition of Chlorphenamine H1-Antihistamine Action?,"Chlorphenamine (chlorpheniramine) is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Pheniramine H1-Antihistamine Action?,"Pheniramine is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Dexchlorpheniramine H1-Antihistamine Action?,"Dexchlorpheniramine is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Brompheniramine H1-Antihistamine Action?,"Brompheniramine is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Dexbrompheniramine H1-Antihistamine Action?,"Dexbrompheniramine is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Triprolidine H1-Antihistamine Action?,"Triprolidine is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Dimetindene H1-Antihistamine Action?,"Dimetindene is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Mepyramine H1-Antihistamine Action?,"Mepyramine (pyrilamine) is a first-generation ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Antazoline H1-Antihistamine Action?,"Antazoline is a first-generation ethylenediamine H1-antihistamine.  H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Chloropyramine H1-Antihistamine Action?,"Chloropyramine is a first-generation ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Talastine H1-Antihistamine Action?,"Talastine is a first-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Tripelennamine H1-Antihistamine Action?,"Tripelennamine is a first-generation ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Histapyrrodine H1-Antihistamine Action?,"Histapyrrodine is a first-generation ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Methapyrilene H1-Antihistamine Action?,"Methapyrilene is a first-generation ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions. Methapyrilene, formerly marketed in many drug products, was shown to be a potent carcinogen. Manufacturers voluntarily withdrew methapyriline drug products from the market in May and June 1979 (DB04819)."
What is the definition of Thonzylamine H1-Antihistamine Action?,"Thonzylamine is a first-generation ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Diphenhydramine H1-Antihistamine Action?,"Diphenhydramine is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Carbinoxamine H1-Antihistamine Action?,"Carbinoxamine is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Doxylamine H1-Antihistamine Action?,"Doxylamine is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Orphenadrine H1-Antihistamine Action?,"Orphenadrine is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Bromodiphenhydramine H1-Antihistamine Action?,"Bromodiphenhydramine (Bromazine) is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Clemastine H1-Antihistamine Action?,"Clemastine is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Chlorphenoxamine H1-Antihistamine Action?,"Chlorphenoxamine (Phenoxene) is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Diphenylpyraline H1-Antihistamine Action?,"Diphenylpyraline is a first-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Phenyltoloxamine H1-Antihistamine Action?,"Phenyltoloxamine is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Cyclizine H1-Antihistamine Action?,"Cyclizine is a first-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Chlorcyclizine H1-Antihistamine Action?,"Chlorcyclizine is a first-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Hydroxyzine H1-Antihistamine Action?,"Hydroxyzine is a first-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Meclizine H1-Antihistamine Action?,"Meclizine (Meclozine) is a first-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Buclizine H1-Antihistamine Action?,"Buclizine is a first-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Oxatomide H1-Antihistamine Action?,"Oxatomide is a first-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Cetirizine H1-Antihistamine Action?,"Cetirizine is a second-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Cinnarizine H1-Antihistamine Action?,"Cinnarizine is a first-generation piperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Levocetirizine H1-Antihistamine Action?,"Levocetirizine is a second-generation piperazine H1-antihistamine. It has also been labeled as a third-generation antihistamine because it is developed from a second-generation antihistamine (cetirizine). H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Promethazine H1-Antihistamine Action?,"Promethazine is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Alimemazine H1-Antihistamine Action?,"Alimemazine (trimeprazine) is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Cyproheptadine H1-Antihistamine Action?,"Cyproheptadine is a first-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Phenbenzamine H1-Antihistamine Action?,"Phenbenzamine is a first-generation ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Fenethazine H1-Antihistamine Action?,"Fenethazine (phenethazinum) is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Hydroxyethylpromethazine H1-Antihistamine Action?,"Hydroxyethylpromethazine is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Isothipendyl H1-Antihistamine Action?,"Isothipendyl is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Mequitazine H1-Antihistamine Action?,"Mequitazine is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Methdilazine H1-Antihistamine Action?,"Methdilazine is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Oxomemazine H1-Antihistamine Action?,"Oxomemazine is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Azatadine H1-Antihistamine Action?,"Azatadine is a first-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Ketotifen H1-Antihistamine Action?,"Ketotifen is a first-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Doxepin H1-Antihistamine Action?,"Doxepin is a first-generation tricyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Acrivastine H1-Antihistamine Action?,"Acrivastine is a second-generation alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Astemizole H1-Antihistamine Action?,"Astemizole is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Bepotastine H1-Antihistamine Action?,"Bepotastine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Bilastine H1-Antihistamine Action?,"Bilastine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Loratadine H1-Antihistamine Action?,"Loratadine is a second-generation tricyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Desloratadine H1-Antihistamine Action?,"Desloratadine is a second-generation tricyclic H1-antihistamine. It has also been labeled as a third-generation antihistamine because it is developed from a second-generation antihistamine (loratadine). H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Ebastine H1-Antihistamine Action?,"Ebastine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Terfenadine H1-Antihistamine Action?,"Terfenadine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Fexofenadine H1-Antihistamine Action?,"Fexofenadine is a second-generation piperidine H1-antihistamine. It has also been labeled as a third-generation antihistamine because it is developed from a second-generation antihistamine (terfenadine). H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Levocabastine H1-Antihistamine Action?,"Levocabastine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Mizolastine H1-Antihistamine Action?,"Mizolastine (mizollen) is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Rupatadine H1-Antihistamine Action?,"Rupatadine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Olopatadine H1-Antihistamine Action?,"Olopatadine is a second-generation tricyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Azelastine H1-Antihistamine Action?,"Azelastine is a second-generation H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Thiazinamium H1-Antihistamine Action?,"Thiazinamium is a first-generation phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Quifenadine H1-Antihistamine Action?,"Quifenadine is a second-generation H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Betahistine H1-Antihistamine Action?,"Betahistine is a first-generation H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Emedastine H1-Antihistamine Action?,"Emedastine is a first-generation ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Flunarizine H1-Antihistamine Action?,"Flunarizine is a first-generation H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Mebhydrolin H1-Antihistamine Action?,"Mebhydrolin is a first-generation H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Phenindamine H1-Antihistamine Action?,"Phenindamine is a first-generation tricyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Epinastine H1-Antihistamine Action?,"Epinastine is a second-generation tetracyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Tolpropamine H1-Antihistamine Action?,"Tolpropamine is an alkylamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Embramine H1-Antihistamine Action?,"Embramine is an ethanolamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Latrepirdine H1-Antihistamine Action?,"Latrepirdine is a tricyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Thenyldiamine H1-Antihistamine Action?,"Thenyldiamine is an ethylenediamine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Propiomazine H1-Antihistamine Action?,"Propiomazine is a phenothiazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Clocinizine H1-Antihistamine Action?,"Clocinizine is a first-generation diphenylmethylpiperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Homochlorcyclizine H1-Antihistamine Action?,"Homochlorcyclizine is a diphenylmethylpiperazine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Temelastine H1-Antihistamine Action?,"Temelastine is a second-generation H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Alcaftadine H1-Antihistamine Action?,"Alcaftadine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Bamipine H1-Antihistamine Action?,"Bamipine is a first-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Deptropine H1-Antihistamine Action?,"Deptropine is a tricyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Quetiapine H1-Antihistamine Action?,"Quetiapine is a tricyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Mirtazapine H1-Antihistamine Action?,"Mirtazapine is a tetracyclic H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Pimethixene H1-Antihistamine Action?,"Pimethixene is a thioxanthene H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Pyrrobutamine H1-Antihistamine Action?,"Pyrrobutamine is an H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Thenalidine H1-Antihistamine Action?,"Thenalidine is a piperidine H1-antihistamine that was withdrawn from Canadian, US, and UK markets in 1963 due to concerns involving neutropenia (DB04826). H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Tritoqualine H1-Antihistamine Action?,"Tritoqualine is an H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions."
What is the definition of Histamine H1 Receptor Activation?,"Histamine is a ubiquitous messenger molecule released from mast cells, basophils, enterochromaffin-like cells, and neurons. Its various actions are mediated by histamine receptors H1, H2, H3, and H4. Histamine receptor H1 belongs to the family of G-protein-coupled receptors (GPCRs), and it is expressed in smooth muscles, on vascular endothelial cells, in the heart, and in the central nervous system. It is linked to an intracellular G-protein (Gαq) that activates phospholipase C and the phosphatidylinositol (PIP2) signalling pathway which promotes inflammatory processes through calcium ion release and expression of the NF-κB immune response transcription factor. H1-antihistamines inactivate the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Upon binding by histamine, the H1 receptor allosterically activates the G-protein by exchanging GDP for GTP at the G-protein's alpha subunit (Gαq). This results in the dissociation of a Gαq-GTP monomer and a Gβγ dimer from the receptor (Wikipedia). Gαq-GTP activates phospholipase C-beta which cleaves the membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2) into the secondary messengers inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). IP3 diffuses through the cytoplasm to the ER and binds to the inositol 1,4,5-trisphosphate (Ins3P) receptor, releasing calcium from the endoplasmic reticulum into the cytoplasm. An increase in the calcium concentration results in increased mediator release and decreased mast cell stability. Both calcium and DAG activate the kinase activity of protein kinase C beta (PKC). Among many other functions, PKC activates NF-κB. This leads to increased antigen presentation and increased expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors."
"What is the definition of Stilbenoid, Diarylheptanoid, and Gingerol Biosynthesis?","Stilbenoids are a family of phenylpropanoids which contain a 1,2-diphenylethylene moiety that exist in the plant kingdom and have a variety of biological functions (PMID: 23014926). Diarylheptanoids are another group of phenylpropanoids that are found in plants which have a 1,7-diphenylheptane skeleton (PMID: 21121274). Gingerols are a group of compounds containing a gingerol moiety, some of which are known to be useful for medication purposes (PMID: 26228533). In Arabidopsis, the stilbenoid, diarylheptanoid, and gingerol biosynthesis pathway takes place in the endoplasmic reticulum. This pathway involves coumaroyl-CoA sourced either directly from phenylpropanoid biosynthesis or derived from cinnamoyl-CoA in a reaction catalyzed by cinnamate-4-hydroxylase. Removal of a CoA group from coumaroyl-CoA and a reaction of coumaroyl-CoA with either shikimic acid or quinic acid produces 4-coumaroylshikimic acid or coumaroyl quinic acid. This is catalyzed by hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase. CYP98A3 enzyme catalyzes hydroxylation of the products to produce caffeoylshikimic acid or chlorogenic acid respectively. Further reaction of products with CoA, catalyzed again by hydroxycinnamoyl-CoA shikimate/quinate hydroxycinnamoyl transferase, produces caffeoyl-CoA. Caffeoyl-CoA is then reacted with S-adenosyl-L-methionine to produce feruloyl-CoA with catalyzation by caffeoyl-CoA O-methyltransferase. 1-dehydro-6-gingerdione and 6-gingerol may then be further derived from feruloyl-CoA."
What is the definition of Riboflavin Metabolism?,"Riboflavin, also known as vitamin B2, belongs to the class of organic compounds known as flavins. These are compounds containing a flavin (7,8-dimethyl-benzo[g]pteridine-2,4-dione) moiety, with a structure characterized by an isoalloaxzine tricyclic ring. Like the other B vitamins, it supports energy production by aiding in the metabolizing of fats, carbohydrates, and proteins. Riboflavin is an important component of the cofactors flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). They act as electron carriers in a number of oxidation-reduction (redox) reactions involved in energy production and in numerous metabolic pathways including fatty acid metabolism, the citrate cycle, and the electron transport chain. Riboflavin metabolism in Arabidopsis thaliana takes place in the chloroplast and it includes two subpathways: purine metabolism and the pentose phosphate pathway. From purine metabolism, GTP is produced which is then catalyzed by GTP cyclohydrolase II to produce 2,5-diamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one which undergoes deamination to produce 5-amino-6-(5'-phosphoribosylamino)uracil and ammonia. 5-Amino-6-(5'-phosphoribosylamino)uracil gets reduced to 5-amino-6-(5-phospho-D-ribitylamino)uracil by a reductase, then 5-amino-6-(5-phospho-D-ribitylamino)uracil phosphatase removes the phosphate group from 5-amino-6-(5-phospho-D-ribitylamino)uracil to produce 5-amino-6-(1-D-ribitylamino)uracil. 5-Amino-6-(1-D-ribitylamino)uracil with L-3,4-dihydroxybutan-2-one-4-phosphate synthase then act as substrate in the reaction catalyzed by 5-amino-6-(D-ribitylamino)uracil butanedionetransferase to produce 6,7-dimethyl-8-(D-ribityl)lumazine, this which is synthesized to riboflavin and 5-amino-6-(1-D-ribitylamino)uracil. Riboflavin is then catalyzed by a riboflavin kinase to produce FMN. FMN can also get dephosphorylated back to riboflavin. In A. thaliana, FMN could also be produced by FAD nucleotidohydrolase."
What is the definition of Lipoic Acid Metabolism?,"Lipoic acid, also known as α-lipoic acid and thioctic acid, is an organosulfur (sulfur-containing) coenzyme. Lipoic acid is an essential cofactor of dehydrogenase enzymes involved in the oxidative decarboxylation of 2-oxoacids and the glycine cleavage (glycine decarboxylase) system. Lipoic acid is derived from the 8-carbon fatty acid, octanoic acid. In most eukaryotes, lipoic acid is synthesised in mitochondrion. However, in plants, the biosynthetic pathway is present in plastids in addition to mitochondria. Lipoic acid is made in animals normally, and is essential for aerobic metabolism. Lipoic acid metabolism starts by the precursor, Octanoyl-[acyl-carrier-protein], which is made via fatty acid biosynthesis. Octanoyl-[acp] can be catalyzed by either lipoyl synthase (LipA) or lipoyl(octanoyl) transferase (LipB), to produce lipoyl-[acp] or protein N6-(octanoyl)lysine respectively. Lastly, protein N6-(lipoyl)lysine is generated via synthesis of protein N6-(octanoyl)lysine by LipA, or via the transfer of a lysine group to lipoyl-[acp] by LipB."
What is the definition of Indole Alkaloid Biosynthesis?,"Indole alkaloids are a large class of alkaloids, some of which are used for medical purposes (Wikipedia). The known components of the indole alkaloid biosynthesis pathway in Arabidopsis thaliana are 3 separate reactions, each of which involves reaction with a water molecule. With catalyzation by strictosidine synthase, 3-alpha(s)-strictosidine reacts with water to produce tryptamine and secologanin. With catalyzation by polyneuridine aldehyde esterase, polyneuridine aldehyde reacts with water to form 16-epivellosimine, carbon dioxide, and methanol. And with catalyzation by acetylajmaline esterase, 17-o-acetylnorajmaline reacts with water as well to form norajmaline and acetate."
What is the definition of Isoquinoline Alkaloid Biosynthesis?,"Isoquinoline alkaloids are a group of alkaloids which are derived from from tyrosine, some of which have medical applications (PMID:23666088). Typically, the isoquinoline alkaloid biosynthesis pathway begins with L-tyrosine (PMID:23666088). In Arabidopsis thaliana, there are some known reactions of this pathway. With catalyzation by either tyrosine aminotransferase or aspartate aminotransferase, L-tyrosine is reacted with oxoglutaric acid to produce hydroxyphenylpyruvic acid and L-glutamic acid. Alternatively, L-tyrosine may undergo decarboxylation to become tyramine with catalyzation by tyrosine decarboxylase. The hydroxylated form of L-tyrosine, L-dopa, may also undergo decarboxylation catalyzed by tyrosine decarboxylate, forming dopamine. Dopamine may be then used in other pathways, such as the tyrosine metabolism pathway, or undergo further reaction with catalyzation by amine oxidase to produce 3,4-dihydroxyphenylacetaldehyde."
What is the definition of Vitamin B6 Metabolism ?,"Vitamin B6 is a water-soluble vitamin essential for all living organisms. It is an important cofactor for enzymatic reactions in over one hundred different cellular reactions and processes. Vitamin B6 exists in different natural forms called vitamers, which are produced by plants, bacteria, and fungi, but not by animals and humans. These vitamers include: pyridoxal (PL), pyridoxine (PN) and pyridoxamine (PM) and their phosphorylated vitamers, PLP, PNP and PMP respectively. Vitamin B6 metabolic pathway was mainly characterized in E. coli, however most organisms, including plants, utilize an alternate pathway. In plants, the various vitamers can be produced via different specific pathways. In A. thaliana, this biosynthetic pathway involves few subpathways, which include: glycolysis, pentose phosphate pathway (PPP), and glyoxylate and dicarboxylate metabolism. Glyceraldehyde 3-phosphate produced by glycolysis and ribulose 5-phosphate produced by PPP are synthesized to pyridoxal 5-phosphate by a synthase. Pyridoxal 5-phosphate is then dephosphorylated to pyridoxal. Pyridoxal, a form of vitamin B6, could act as a precursor for butanoate metabolsim. Moreover, from PPP, 2-Oxo-3-hydroxy-4-phosphobutanoate is produced, this is synthesized to O-phospho-4-hydroxy-L-threonine and then to 4-hydroxy-L-threonine. Pyridoxine could also be produced after a multistep reaction from 4-hydroxy-L-threonine, which is then synthesized to pyridoxal. Glycoaldehyde produced from glyoxylate and dicarboxylate metabolism is converted to pyridoxine. Pyridoxine could also undergo phosphorylation where it is converted to pyridoxine phosphate which is then synthesized to pyridoxal 5-phosphate where the later is dephosphorylated to pyridoxal. Pyridoxal could also be synthesized to pyridoxamine, this that is phosphorylated to pyridoxamin 5-phosphate, which is then synthesized to pyridoxal 5-phosphate. "
"What is the definition of Tropane, Piperidine, and Pyridine Alkaloid Biosynthesis?","Tropane, piperidine, and pyridine alkaloids are alkaloid compounds found in some plants containing a tropane, piperidine, or pyridine ring respectively (Wikipedia). In Arabidopsis thaliana, the tropane, piperidine and pyridine alkaloid biosynthesis pathway consists of several separate reactions that are known. L-phenylalanine, which may be sourced from the phenylalanine, tyrosine, and tryptophan biosynthesis pathway or the phenylalanine metabolism pathway, may reversibly react with oxoglutaric acid to produce phenylpyruvate  (aka. 2-oxo-3-phenylpropanoic acid) and L-glutamic acid. This reaction may be catalyzed by tyrosine aminotransferase, aspartate aminotransferase, or histidinol phosphate aminotransferase.  Primary amine oxidase may catalyze the reactions of N-methylputrescine or cadaverine with oxygen and hydrogen to produce hydrogen peroxide, ammonia, and either 1-methylpyrrolinium or 5-aminopentanal respectively. Tropinone may react with hydrogen and NADPH to produce tropine and NADP, with catalyzation by tropinone reductase."
What is the definition of Caffeine Metabolism?,"Caffeine is compound that originates from plants which is widely consumed worldwide (Wikipedia). Though caffeine is not normally found in Arabidopsis thaliana, some independent reactions of the plant caffeine metabolism pathway are still present. With catalyzation by xanthine dehydrogenase, there are four compounds in this pathway that water and oxygen may react with to produce hydrogen peroxide and a different product depending on the compound. In this way, the compounds 1-methylxanthine, paraxanthine, theobromine or 7-methylxanthine may be converted to 1-methyluric acid, 1,7-dimethyluric acid, 3,7-dimethyluric acid or 7-methyluric acid respectively. In addition, in the peroxisome, uricase may catalyze the conversion of 1,3,7-trimethyluric acid, oxygen and water to 3,6,8-trimethylallantoin, carbon dioxide, and hydrogen peroxide."
What is the definition of Monobactam Biosynthesis?,"Monobactams are a group of beta-lactam antibiotics which contain a beta-lactam ring that is alone and not fused to another ring (Wikipedia). In Arabidopsis thaliana, the monobactam biosynthesis pathway takes place in the chloroplast. Aspartokinase 1 catalyzes the conversion of L-aspartic acid with ATP into L-aspartyl-4-phosphate and ADP.  With asparate-semialdehyde dehydrogenase catalyzation, L-aspartyl-4-phosphate is dephosphorylated by reaction with NADPH, and hydrogen to produce L-aspartate-semialdehyde, NADP, and phosphate. L-aspartate-semialdehyde is then reacted with pyruvic acid to produce (2S,4S)-4-hydroxy-2,3,4,5-tetrahydrodipicolinic acid and water, with catalyzation by 4-hydroxy-tetrahydrodipicolinate synthase. With catalyzation by 4-hydroxy-tetrahydrodipicolinate reductase, (2S,4S)-4-hydroxy-2,3,4,5-tetrahydrodipicolinic acid may be dehydroxylated in reaction with hydrogen and either NADH or NADPH to produce tetrahydrodipicolinate, water, and either NAD or NADP respectively. "
What is the definition of Lysophosphatidic Acid LPA1 Signalling?,"Lysophosphatidic acid (LPA) is a water-soluble phospholipid derivative and a potent signalling molecule that binds to six known lysophosphatidic acid receptors (LPARs), named LPA1-LPA6. All six receptors belong to the G protein-coupled receptor (GPCR) superfamily which initiates intracellular signalling cascades via four G protein classes differentiated by their α subunit type: Gαs, Gαi/o, Gαq/11, Gα12/13. GPCRs mediate a wide range of biological processes, including cell survival, proliferation, migration, and differentiation, vascular regulation, and cytokine release. Due to LPA's physiological importance, abnormal LPA signalling likely contributes to the pathophysiology of many diseases. LPA biosynthesis proceeds through two major pathways: (1) the conversion of lysophospholipids (e.g. LPC, LPE, LPS) into LPA via autotaxin (ATX/Enpp2) and (2) the conversion of phosphatidic acid (PA) into LPA via phospholipase A1 or A2 (PLA1/PLA2). The binding of LPA to an LPAR allosterically activates the heterotrimeric G protein by exchanging GDP for GTP at the G protein's alpha subunit. This results in the dissociation of a Gα-GTP monomer and a Gβγ dimer from the receptor which allows both complexes to begin signalling cascades via downstream effectors. LPA1 signalling has been implicated in important processes such as cell survival, proliferation, adhesion, migration, immune function, and myelination. This receptor can couple with the G proteins Gαi/o, Gαq/11, and Gα12/13. The Gαi/o subunit inhibits the enzyme adenylyl cyclase (AC) which catalyzes the production of the important secondary messenger 3',5'-cyclic AMP (cAMP) from adenosine triphosphate (ATP). Other downstream effectors of Gαi/o include the MAPK/ERK pathway, the PI3K/Akt pathway, and P13K/Rac signalling. The Gαq/11 subunit activates phospholipase C (PLC) which cleaves the membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2) into the secondary messengers inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). IP3 diffuses through the cytoplasm to the ER and binds to the inositol 1,4,5-trisphosphate (Ins3P) receptor, releasing calcium from the endoplasmic reticulum into the cytoplasm. Both calcium and DAG activate the kinase activity of protein kinase C beta (PKC). Among many other functions, PKC activates NF-κB. This leads to increased antigen presentation and increased expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. The Gα12/13 subunit regulates cell motility and cytoskeletal remodelling by activating the Rho/ROCK and Rho/SRF pathways."
"What is the definition of Activation of cAMP-dependent protein kinase, PKA?","Protein phosphorylation is one of the most important processes for cellular regulation and signal transduction in eukaryotic cells. Unlike cell cycle-dependent protein kinase 2 and mitogen-activated protein kinase, the catalytic (C) subunit of cAMP-dependent protein kinase (PKA) normally is assembled as an active enzyme with a fully phosphorylated activation loop. "
What is the definition of Ahr Signal Transduction Pathway?,"The aryl hydrocarbon receptor, known as AHR, is a normally cytosolic transcription factor that can bind to foreign compounds such as flavonoids and indoles from foods, as well as synthetic ligands including polychlorobiphenyls (PCBs) and polychlorinated dibenzo-p-dioxins (PCDD). This includes 2,3,7,8-tetrachlorodibenzodioxin (TCDD), which is the ligand shown in this pathway.AHR interacts with heat shock protein 90 (HSP90AA1), which acts as a chaperone for it. After this association, the ligand, in this case TCDD, can form a covalent bond with the complex in the cell's cytoplasm. This binding causes AHR and the rest of the complex to translocate into the nucleus of the cell. Once in the nucleus, the heat shock protein dissociates, leaving binding sites which the AHR nuclear translocator (ARNT) then binds to. Finally, the AHR/ARNT complex can interact, either directly or indirectly, with the DNA, in this case specifically a dioxin response element. With other ligands, the complex will bind to the equivalent DNA that corresponds to the genes that allow metabolism of the ligand."
What is the definition of Apoptotic DNA Fragmentation and Tissue Homeostasis?,"Apoptotic endonucleases degrade chromosomal DNA during programmed cell death. ICAD and CAD exist in the nucleus in normal cells and is a major endonuclease in apoptosis. Its activation is normally caspase dependent. EndoG resides in mitochondria in normal cells and travels to the nucleus, where it fragments chromosomal DNA upon activation of apoptosis. Once released from the mitochondrial intermembrane space, EndoG activity is caspase independent."
What is the definition of BTG Family Proteins and Cell Cycle Regulation?,"BTG Family Member-2 (BTG2) is endowed with antiproliferative activity. The expression of BTG2 in cycling cells induces accumulation of hypophosphorylated, growth-inhibitory forms of Retinoblastoma protein(Rb) and lead to G1 arrest through impairment of DNA synthesis. Rb is a nuclear phosphoprotein whose phosphorylation state oscillates regularly during the cell cycle. Hypophosphorylated Rb associates with members of the E2F family of transcription factors, impairing their activity and leading to a cell cycle block in G1. Conversely, the phosphorylation of Rb inactivates its growth suppression activity by freeing E2F molecules, thus enabling them to transactivate genes required for the progression of the cell into S phase and the remainder of the cell cycle. Cyclin-dependent kinases (CDKs) are the molecules responsible for Rb phosphorylation and its consequent inactivation."
What is the definition of Nitric Oxide Signaling Pathway?,"Nitric oxide (NO) is a neurotransmitter that synthesized from L-arginine with faciltation of nitric oxide synthase (NOS). Nitric oxide is essential and required in central nervous system (CNS) and peripheral nervous system (PNS). Nitric oxide has several important functions such as immune responses, blood flow regulation and modulation of neurotransmission. Nitric oxide also participates in controlling sleep, adjusting body temperature, neurosecretion as well as synaptic modulation and plasticity in CNS. While in PNS, nitric oxide participates in visceral smooth muscle relaxation as well as vasodilation mediation."
What is the definition of Ion Channels and Their Functional Role in Vascular Endothelium?,"In endothelial cell, ion channels such as agonist-activated nonselective Ca(2+)-permeable cation channels, cyclic nucleotide-activated nonselective cation channels, and store-operated Ca(2+) channels or capacitative Ca(2+) entry are controlled by intracellular Ca(2+) signals. Some of the channels are expressed by trp gene family. Ca(2+) entry is also controlled by large-conductance Ca(2+)-dependent BK(Ca) channels (slo), inwardly rectifying K(+) channels, Ca(2+)-activated Cl(-) channel and volume-regulated anion channel (VRAC). VRAC channels can also transport organic osmolytes and amino acid. "
What is the definition of P53 Signaling Pathway?,"P53 signaling plays an important role in the co-ordination of the cellular response to different types of stress such as DNA damage and hypoxia. Inactivation of p53 has been implicated in tumor progression, it is thought that more than half of all cancers may involve p53-inactivating mutations. DNA damage, activated oncogenes and oxidative stress can produce stress signals to activate P53 protein, which is a transcriptional activator of p53-regulated genes. Activation of p53-regulated genes will lead to cellular senescence, cell cycle arrest or apoptosis. Activated p53-regulated genes will also communicate with nearby cells for the purpose of DNA repair or feedback loop set-up that can either strengthen or weaken the stress responses of p53 protein."
What is the definition of Phospholipase C Signaling Pathway ?,Phospholipase C pathways is one of the major intracellular signalling pathways regulating hormones. It functions to activate inositol lipid signalling pathways causing the hydrolysis of PIP2 by PLC to IP3 and diacylglycerol to activate protein kinase C. IP3 releases calcium from the endoplasmic reticulum. PIP3 is an important regulator of AKT signaling and downstream pathways. 
What is the definition of Ras Signaling Pathway ?,"RAS signalling pathway is one of the main pathways to transduce intracellular signals in response to mitogens to controls cell growth, survival and anti-apoptotic programs. RAS proteins are GTP-binding proteins and must be bound to GTP to be active. Active RAS binds and activates effector enzymes that control cell proliferation, survival and other cell behaviours. RAS interacts directly with the catalytic subunit of PI3K to activate lipid kinases controlling the activity of downstream enzymes. Some of these kinases have anti-apoptotic activity, playing an important role in the survival signal of RAS. PI3K is also involved in the regulation of the actin cytoskeleton and transcription factor pathways. RAS also effects exchange factors causing inhibition of transcription factors from FoxO family, part of promoting cell cycle arrest and apoptosis. Normal function of these proteins require post-transcriptional modification. Pathway mutations in activation may result in human tumours. "
What is the definition of TNF/Stress Related Signaling?,"Tumour necrosis factor alpha (TNF-a) is a cytokine that activates TNF rector 1 (TNFR1) signalling complex.  TNFR1 mediates cell death signalling and inflammation in response to cytokines, bacteria and cellular stress. The classical NFkB pathway involves activation of  TNF receptor associated factor 2, receptor interacting serine/threonine protein kinase and death domains which activate the IKK complex, phosphorylating the IKB proteins triggering their degradation resulting in NF-kB dimers dissociation and release. Caspase 2 interacts with TNF-receptor associated factor 2 and receptor interacting serine/threonine protein kinase to activate NFkB. Mitogen activated protein kinases of the MAP3K family are also involved in TNFR1-mediated IKK activation. Mitogen activated kinases can phosphorylate IKK to activate it as well. Activation of Mitogen-activated protein kinase 8 and 14 are involved in the cross-talk of other inflammatory pathways. "
What is the definition of Rac 1 Cell Motility Signaling Pathway?,"Rac1 is signaling protein part of the Rho GTPase family it is involved in cell motility, cell growth and cytoskeletal reorganization. Rac1 activity is regulated by guanine nucleotide exchange factors (GEFs). GEFs cause the release of GDP, allowing GDP to bind and Rac1 to become activated. GTPase-activated proteins (GAPs) down regulate the activity of GEFs be stimulating the inactivation via binding of GDP to Rac1. Active Rac1 stimulates proteins (ie. Wiskott–Aldrich syndrome) leading to actin polymerization. Actin polymerization is also regulated by cofilin. PAK proteins are critical effectors to cytoskeleton reorganization. PAK1 phosphorylates and activates LIM kinase. LIM kinase then phosphorylates cofilin, inactivating it leading to reduced actin filament severing and depolymerization, therby increasing polymerized actin. Rac1 stimulates lamellipodia and filopodia formation which are involved in cell movement and sensing the environment.  It is proposed that PAK1 is involved in the phosphorylation of myosin light chain affecting myosin light chain phosphorylation. "
What is the definition of Cadmium Induces DNA Synthesis and Proliferation in Macrophages ?,"Cadmium (Cd(2+)) exposure increases the risk of cancer in humans and animals. Humans may come into contact with cadmium when smoking and ingesting contaminated food. This will increase the risk of lung cancer and prostate cancer. In the millimolar range, cadmium will inhibit cell growth. Cadmium induces DNA synthesis and proliferation and affects signal transduction and mobilization in macrophages. At micromolar concentrations, cadmium significantly increased cell division as judged by thymidine uptake and cell counts. Activating this pathway will increase the availability of the transcription factor NF(kappa)B and will activate the early genes c-fos and c-myc."
What is the definition of Growth Hormone Signaling Pathway ?,"Growth hormone is the hormone primarily responsible for body growth. Growth hormone (GH) binds membrane-bound growth hormone receptor (GHR) to activate and enhance the binding of JAK2. This stimulates phosphorylation of JAK2 and GHR. JAK2 initiates GH signal transduction. This activation initiates multiple signalling pathways: STAT transcription factors, activation of kinases, and insulin receptor pathways. GH stimulates Signal Transducer and Activator of Transcription (STAT) and its binding to Sis-inducible elements of the c-fos promoter. C-fos expression has input from multiple pathways. The serum response element binds serum response factors and other complex transcription factors regulated by GH via the MEK/ERK pathway. STAT 5 is also involved in the synthesis of many GH-sensitive genes. STAT proteins are phosphorylated and then released from the GH/JAK2 complex. Once released, they become dimers and move to the nucleus to bind binding sites in GH-regulated genes. STAT proteins may also dimerize with other transcription factors to regulate transcription. GH can stimulate glucose transport in the cell through JAK2 stimulation of IRS proteins that recruit PI3K to regulate glucose transport."
What is the definition of Phosphatidylcholine Biosynthesis PC(16:0/16:0)?,"Phosphatidylcholines (PC) are a class of phospholipids that incorporate a phosphocholine headgroup into a diacylglycerol backbone. They are the most abundant phospholipid in eukaryotic cell membranes and has both structural and signalling roles. In eukaryotes, there exist two phosphatidylcholine biosynthesis pathways: the Kennedy pathway and the methylation pathway. The Kennedy pathway begins with the direct phosphorylation of free choline into phosphocholine followed by conversion into CDP-choline and subsequently phosphatidylcholine. It is the major synthesis route in animals. The methylation pathway involves the 3 successive methylations of phosphoethanolamine to form phosphocholine which is then funnelled into the Kennedy pathway to make phosphatidylcholine. In plants, phosphatidylcholine biosynthesis is implemented using a mix between the two pathways. An alternative of the methylation pathway uses phosphatidylethanolamine as a starting compound, but no enzyme has been found in Arabidopsis to catalyze the first methylation to form phosphatidyl-N-methylethanolamine. Many enzymes involved in this pathway are localized to the cell membrane but are not drawn as such for clarity. Instead, they are indicated with a dark green colour and appear to be free floating in the cytosol. The first reaction of the Kennedy pathway involves the membrane-localized enzyme choline/ethanolamine kinase catalyzing the conversion of choline into phosphocholine. Second, choline-phosphate cytidylyltransferase catalyzes the conversion of phosphocholine to CDP-choline. Last, choline/ethanolaminephosphotransferase, localized to the cell membrane, catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors. Note that phosphatidylcholine can be converted to either phosphocholine by a non-specific phospholipase or converted to choline by phospholipase D. Phosphocholine can also be converted to choline via phosphoethanolamine/phosphocholine phosphatase. The methylation pathway begins with serine decarboxylase catalyzing the biosynthesis of ethanolamine from serine. It requires pyridoxal 5'-phosphate as a cofactor. Next, choline/ethanolamine kinase, localized to the cell membrane, catalyzes the conversion of ethanolamine to phosphoethanolamine. Phosphoethanolamine N-methyltransferase (PEAMT), located in the cytosol, then catalyzes three sequential N-methylation steps to convert phosphoethanolamine to phosphocholine. PEAMT uses S-adenosyl-L-methionine as a methyl donor. Phosphocholine then enters the Kennedy pathway. Alternatively, in a subpathway parallel to the Kennedy pathway, phosphoethanolamine can be converted into phosphatidylethanolamine. Phosphatidylethanolamine is also synthesized from phosphatidylserine in the endoplasmic reticulum by phosphatidylserine decarboxylase. Note that phosphatidylethanolamine can be converted to either phosphoethanolamine by a non-specific phospholipase or converted to ethanolamine by phospholipase D. The two methylated intermediates N-methylethanolamine phosphate and N-dimethylethanolamine phosphate can also undergo reactions parallel to the Kennedy pathway to form the methylated intermediates of phosphatidylethanolamine (otherwise catalyzed by phosphatidyl-N-methylethanolamine N-methyltransferase, localized to the endoplasmic reticulum membrane, to form phosphatidylcholine)."
What is the definition of EGF Signalling Pathway?,Epidermal growth factor (EGF) is a potent polypeptide mitogen that initiates its biological activity by interacting with the cell surface. The E G F receptors are both transmembrane proteins with cytosolically exposed tyrosine specific protein kinases which are stimulated by ligand binding. Current data strongly suggests that these kinases are causally linked to many if not all of the biological activities of the EGF receptors. Transmembrane signalling is the result of a composite of ligand-receptor interactions in the endosome (stimulation) and modifications of the primary or quaternary structure of the receptor (activation).
What is the definition of GnRH Signaling Pathway?,"Gonadotropin-releasing hormone (GnRH), a hypothalamic neuropeptide, is a main regulator of male and female reproductive function in mammals. GnRH is required for reproduction. GnRH is secreted from the hypothalamus and acts on G-protein coupled receptors in the anterior pituitary. GnRH regulates the production and release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) gonadotropins, controlling gametogenesis and steroidogenesis. Activated phospholipase C activates IP3 to release intracellular calcium from the endoplasmic reticulum thereby increasing cytoplasmic calcium. Diacylglycerol is also activated by phospholipase C to stimulate the PKC pathway. The PKC pathway leads to the activation of epidermal growth factor (EGF) receptor and mitogen-activated protein kinases (MAPKs), extracellular-signal-regulated kinase (ERK), Jun N-terminal kinase (JNK) and p38 MAPK. MAPKs are activated and translocate to the nucleus causing the transcription of gonadotropin genes. GnRH also activates G proteins causing the activation of adenylyl cyclase to generate cAMP. cAMP stimulates PKA to phosphorylate and activate transcription factors that translocate to the nucleus for gene transcription. GnRH also promotes secretion of metalloproteinases (MMPs) which regulate the transcription of gonadotropin subunit genes and the GnRHR gene via autocrine/paracrine mechanisms. PKC induces the release of activated MMPs that mediate transactivation of epidermal growth factor receptor (EGFR) which may result in the modulation of gonadotropin subunit genes."
What is the definition of NF-kB Signaling Pathway?,"NF-κB can be found in almost all aminal cell. NF-κB is crucial for cell growth since it can control the cytokine production, DNA transcription as well as cell survival. NF-κB can also response to stress, free radicals, uv irradiation and etc. NF-κB can also response to bacterial and viral antigens; Therefore, it is important for the immune response of infections. Various diseases such as cancer and immune diseases (and more) can be related to inccorect regulation of NF-κB complex. The activation of NF-κB involves two major signalling pathways: the canonical pathways, which responds to diverse stimuli such as ligands of various cytokine receptors, pattern-recognition receptors (PRRs); and noncanonical (or alternative) pathway, which selectively responds to a specific group of stimuli, such as groups of ligands of a subset of TNFR superfamily members (e.g. LTβR, BAFFR, CD40 and RANK). Both pathways are important for regulating immune and inflammatory responses despite their differences in signalling mechanism."
What is the definition of Complement Pathway?,"The complement system includes three separate pathways that lead to complement's activation. These pathways all have different molecules that trigger their activation, but all of them lead to a response by phagocytes as part of a response by the innate immune system.In the alternative pathway, complement factor C3 can spontaneously hydrolyze to form a complex with water. Complement factor D is a protease that can work at the same time, and it cleaves complement factor B into factors Ba and Bb. the C3(H2O) complex can bind to factor Bb, which is a C3 convertase, and works to cleave factor C3 into C3a and C3b more quickly. The C3(H2O)Bb complex also binds factor B, leading to easier cleavage into Ba and Bb by factor D. Following this, complement factor C3b can bind to the surface of cells, and on host cells, proteins on the cell membrane can bind to C3b, preventing it from forming complement factor C5 convertase. However, on pathogen cells, these proteins do not exist, complement factor Bb can bind to two molecules of C3b, forming a C5-convertase which is the end point of the other two pathways.In the lectin pathway, mannan-binding lectin serine proteases (MASP) 1 and 2, as well as mannose-binding protein C bind to carbohydrates, specifically mannose, glucose and sugars with specific hydroxide group placements. These sugars are found in the cell walls of bacteria such as salmonella and listeria, as well as some viruses, including HIV-1, and fungal pathogens, such as candida. After the sugar is bound by the proteins, it activates the serine proteases, which then can cleave complement C2 and C4 into C2a, C2b, C4a and C4b respectively. Factors C4b and C2a (sometimes called C2b) can interact to form C3 convertase, which is identical in function to the C3 convertase formed by the alternative pathway, and it works to cleave C3 into C3a and C3b more quickly. Finally for this pathway, a molecule of C3b interacts with the preexisting C3 convertase complex, forming the C5 convertase complex that cleaves factor C5 into C5a and C5b.The final pathway that leads to this point is the classical complement pathway. This pathway is activated by the binding of aggregated antibody-antigen complexes, as well as components of viral and bacterial cells such as lipopolysaccharides, to the C1q protein. C1q is part of the C1 complex, which also includes C1s and C1r. Binding of a substance to C1q causes a conformational change in C1r and C1s, allowing C1s to become an active protease, which then is able to cleave complement factors C2 and C4 into their a and b fragments, as in the lectin pathway. The remainder of the pathway is identical to that of the lectin pathway. Finally, after cleavage of C5 into C5a and C5b by any of the pathways, complement componenets C6, 7, 8 and 9 can interact with component C5b in order to form the membrane attack complex. This complex attaches to the plasma membrane of pathogen cells, forming a hole in the membrane and allowing diffusion of molecules in the cell, and eventually cell death if enough attack complex form."
What is the definition of Alternative Complement Pathway?,"The alternative complement pathway is a component of the immune system's natural defence against infections. It is a pathway that opsonizes and kills pathogens. The pathway is triggered when the C3b protein directly binds to a microbe, or by an interaction with foreign materials and damaged tissues. The pathway triggers the binding of plasma protein factor B, which allows factor D to cleave factor B into Ba and Bb. Bb remains bound to C3(H2O) to form C3(H2O)Bb (also known as a fluid-phase C3-convertase). This convertase then cleaves multiple C3 proteins into C3a and C3b. The complex is believed to be unstable until it binds properdin, a serum protein. The addition of properdin forms the complex C3bBbP, a stable compound which can bind an additional C3b to form alternative pathway C5-convertase.The C5-convertase of the alternative pathway consists of (C3b)2BbP (sometimes referred to as C3b2Bb). C5-convertase then cleaves C5 into C5a and C5b. C5b binds sequentially to C6, C7, C8 and then to multiple molecules of C9 to form membrane attack complex."
What is the definition of Ubiquitin–Proteasome Pathway?,"The ubiquitin-proteasome pathway is the pathway in which molecules, specifically proteins, are broken down into smaller molecules in the cytosol or in the nucleus.This pathway subsequently has effects in many other pathways and processes. This pathway uses 2 distinct steps. The first step is that the protein being broken down is tagged by multiple ubiquitin units attaching to the protein. The second step is that the protein that has been  tagged degrades as it is catalyzed by the 26S proteasome. This pathway is important for DNA repair, regulating the amount of proteins, and the creation of antigen-peptide. "
What is the definition of Ascorbate Biosynthesis?,L-Ascorbate commonly known as vitamin C is a reducing agent and cofactor in reactions catalyzed by copper-dependent monooxygenases and iron-dependent dioxygenases. It is synthesized from direct hydrolysis of UDP-α-D-glucuronate by enzymes bound to the endoplasmic reticulum membrane. It can be biosynthesized in many plants and bacteria and used as vitamin supplements. Other common uses include being an additive for beverage production and live stock feed. Without sufficient levels of L-ascorbate disorders such as scurvy may develop.
What is the definition of Lectin-Induced Complement Pathway ?,"The lectin-induced complement pathway, also known as the MBL pathway, is a complement activation pathway that is triggered by mannose-binding lectin binding to sugars found on carbohydrates found on pathogens. Unlike other complement pathways, this pathways components do not bind directly to the antibodies attached to the pathogen. The bacteria that MBL binds to include listeria, salmonella, and HIV-1."
What is the definition of Toll-Like Receptor Pathway 1?,"Toll-like receptors (TLRs) are part of the innate immune system. These receptors recognize pathogen-associated molecular patterns from different microbes. TLR2 recognizes a variety of PAMPs including lipoproteins, peptidoglycans, lipotechoic acids, and mannan. TLR3 recognizes viral double-stranded RNA, small interfering RNAsa, and self-RNAs. TLR4 recognizes lipopolysaccharides. TLR7 recognizes single-stranded RNA. TLR9 recognizes bacterial and viral DNA with unmethylated CpG-DNA motifs. TLRs are synthesized in the endoplasmic reticulum, moved to the Golgi, and then recruited to the cell surface or intracellular compartments. TLRs recruit adaptor molecules such as MYD88, TRIF, TIRAP, or TRAM leading to the activation of transcription factors NF-kappa-B causing innate immune responses. MYD88 is recruited by all TLRs. Adaptor TIRAP recruits MYD88 to cell surface TLRs, including TLR2 and TLR4. TLR signaling molecule IRAK1 activation activates TRAF6 causing the activation of IKK complex then NF-kappa-B and kinases. Activated TRAF6 promotes polyubiquination of TRAF6 and TAK1, TAB1, TAB2 complex. TAK1 activates pathways causing activation of IKK complex and NF-kappa-B and MAPK pathways. The IKK complex phosphorylates and activates IKK-beta. IKK complex also phosphorylates I-kappa-B-alpha allowing dissociation and translocation of NF-kappa-B to the nucleus resulting in proinflammatory gene expression. Activated TAK1 complex also activates p38 and JNK, regulating the activation of AP-1 transcription factors to regulate inflammatory responses. Many transmembrane molecules, such as glycophosphatidylinositol-anchored protein CD14, also regulate TLR signaling pathways."
What is the definition of De Novo Triacylglycerol Biosynthesis TG(14:0/14:0/14:0)?,"A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and other animals, as well as vegetable fat. They are also present in the blood to enable the bidirectional transference of adipose fat and blood glucose from the liver, and are a major component of human skin oils (Wikipedia). De novo biosynthesis of triglycerides is also known as the phosphatidic acid pathway, and it is mainly associated with the liver and adipose tissue. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). The next three steps are localized to the endoplasmic reticulum membrane. The enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. Next, magnesium-dependent phosphatidate phosphatase catalyzes the conversion of phosphatidic acid into diacylglycerol. Last, the enzyme diacylglycerol O-acyltransferase synthesizes triacylglycerol from diacylglycerol and a fatty acyl-CoA."
What is the definition of Classical Complement Pathway?,"The classical complement pathway is a pathway that is responsible for activating the complement system within the immune system. This pathway begins with the activation of antibodies IgM and IgG. Protein C3 is created, and after a series of reactions, cleaves the C5 protein. This brings phagocytes to the infected area and sets the stage for the coming together of the membrane attack complex (MAC). This complex targets the cell and creates an opening in the membrane, which leads to cell lysis and death. "
What is the definition of CXCR4 Signaling Pathway?,"CXCR4 is a chemokine G-protein-coupled receptor. Chemokine receptors couple to the pertussis toxin-sensitive Gi proteins. It is involved in organogenesis, hematopoiesis, and the immune response. Chemokine stromal cell-derived factor 1 (SDF-1) binds CXCR4. CXCR4 is also a co-receptor for HIV and is involved in the metastasis of some cancers. Pertussis toxin ADP-ribosylates guanine nucleotide binding protein alpha inhibiting (Gai) proteins inhibiting GPCR/Gi coupling. Activated Gai inhibits adenylyl cyclase and activates tyrosine kinases, while activated guanine nucleotide binding protein beta and gamma activate PI3K - regulating gene transcription, cell migration, and cell adhesion. PLC is activated to cause the cleavage of PIP2 to IP3 and DG. This leads to the increase of calcium from the endoplasmic reticulum and the activation of protein kinase C. "
What is the definition of D4-GDI Signaling Pathway?,"Perforin protein forms pores in the membrane to allow for granzyme B to enter the cell.  Granzymes induce apoptosis by activating caspases.  D4-GDP dissociation inhibitor (D4-GDI) is a negative regulator of ras-related Rho Family of GTPases.  D4-GDI binds Rho GTPases to keep the Rho protein in a GDP-bound and inactivate state.  Caspase 3 cleaves D4-GDI into two fragments of 5 kDa and 23 kDa size.  The 23 kDa fragment translocates to the nucleus to activate Jun kinase, a regulator of apoptosis.  Poly (ADP-ribose) polymerase-1 (PARP) is a substrate for caspase-3.  Caspase-3 cleaves PARP into various fragments, this is a hallmark of apoptosis.  PARP functions to detect and repair DNA damage.  Cleavage of PARP by caspase prevents DNA repair, contributing to cell death.  RHO GTPases become activated when released from D4-GDI upon cleavage by caspase-3.  RHO GTPases mediate cytoskeleton changes leading to apoptosis and cell death.  . "
What is the definition of T Cell Receptor Signaling Pathway ?,"The T-cell receptor signalling pathway is an intracellular pathway that depicts how T-cells are activated as part of the cell-mediated immune response. T-cells are a type of lymphocyte produced by the thymus gland (T stands for thymus) that have a unique protein on their surface called the T-cell receptor. The T-cell receptor (TCR) is responsible for recognizing fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules (PMID: 6336315). T-cells are activated when they encounter another immune cell such as a dendritic cell or a B-cell that has digested a protein antigen and displayed the resulting peptide antigen fragments on their surface MHC molecules. These antigen-bound dendritic or B-cells are called antigen-presenting cells or APCs. The MHC-antigen complex from these APCs binds to the TCR of a given T-cell and then, through a series of signalling events (depicted in this pathway), the T-cell begins to secrete cytokines (PMID: 19132916).  Some cytokines help the T-cell mature while other cytokines spur the growth of even more T-cells. The MHC-antigen-TCR binding event activates several signalling pathways such as the PI3K pathway that generates inositol triphosphate (IP3) at the plasma membrane. This leads to the recruitment of signalling molecules like PDK1 (pyruvate dehydrogenase kinase 1), PLC-gamma-1 (phospholipase C-gamma), diacylglycerol (DAG) and others that are essential for the activation of PKC-theta (protein kinase C-theta), and eventually the production of interleukin-2 (IL-2) as well as other cytokines (PMID: 19132916). As shown in this pathway the antigen is first presented to the T-cell receptor (consisting of an alpha and beta subunit) and the CD3 glycoprotein complex (PMID: 19132916). An early event in TCR activation is the phosphorylation of certain tyrosine containing motifs on the cytosolic side of the TCR/CD3 complex by a protein known as lymphocyte protein tyrosine kinase or Lck. After this phosphorylation event, a protein called the zeta-chain associated protein kinase (Zap-70) is recruited to the phosphorylated TCR/CD3 complex where it becomes activated (PMID: 7539035). This promotes the recruitment and phosphorylation of other proteins. For instance, the phosphorylation of SLP-76 by Zap-70 promotes the recruitment of a protein known as Vav (a guanine nucleotide exchange factor), as well as the adaptor proteins NCK and GADS, and an inducible T cell kinase known as Itk. Phosphorylation of PLC-gamma-1 by Itk results in the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) to produce the secondary messengers known as diacylglycerol (DAG) and inositol trisphosphate (IP3). DAG activates PKC-theta and the MAPK/Erk pathways, both promoting transcription factor NF-kappa-B activation. IP3 triggers the release of calcium from the endoplasmic reticulum, which promotes entry of extracellular Ca2+ into the T-cells where it is bound by calmodulin. Calcium-bound calmodulin (Ca2+/CaM) activates the phosphatase known as calcineurin (PMID: 22100452), which promotes IL-2 gene transcription through the transcription factor NFAT (Nuclear factor of activated T-cells) (PMID: 3260404)."
What is the definition of Stat3 Signaling Pathway?,"The STAT3 signalling pathway is a pathway activated by many different cytokines. It has also been found to be activated by many carcinogens. Cytokines are small proteins. These proteins are released by some of the cells in the immune system, and are vital to signalling pathways in the body of mammals. STAT3 is very important in the activation of the expression of certain mediators in the liver.  STAT3 binds at the phosphotyrosine receptor which in turn phosphorylates tyrosine 705 at the C-terminal domain of STAT3, activating STAT3. If a receptor is missing tyrosine-kinase activity it will find tyrosine-kinases that are associated to the receptor, including JAK and Src when it is time for ligand engagement. Thanks to this recruitment,  STAT3 is phosphorylated through the tyrosine phosphorylation cascade. This means that STAT3 is now activated, and its compounds disconnect from the receptor site, and relocate to the nucleus. Once there, the compounds bind to DNA response elements, and take part in many processes against target genes, such as apoptosis and cell proliferation, regulating their transcription. "
What is the definition of Cardiolipin Biosynthesis CL(16:0/16:0/16:0/16:0)?,"Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor."
What is the definition of Toll-Like Receptor Pathway 2?,"Toll-like receptors (TLRs) are a type of pattern recognition receptor that spans the cell membrane and recognizes conserved microbial molecules. TLRs get their name from the toll gene in Drosophila, which produces a protein that is similar in structure to TLR proteins. Each TLR is able to recognize specific unique molecules associated with pathogens, including lipoproteins, lipopolysaccharides, double stranded RNA, flagellin and others. Recognition of pathogen molecules allows the immune system to detect extracellular pathogens.TLR2 can form heterodimers on the surface of the cell's plasma membrane with either TLR1 or TLR6. These dimers, along with another protein known as CD14 as a cofactor, can detect different microbial lipoproteins. Following binding of lipoproteins to these complexes, they activate a protein known as myeloid differentiation primary response protein (MyD88). MyD88 then joins with interleukin-1 receptor-associated kinase 1 (IRAK1) to form a complex.TLR4 is another TLR that detects lipopolysaccharides (LPS) that make up the outer membrane of Gram-negative bacteria. It associates with two other proteins, monocyte differentiation antigen CD14, and lymphocyte antigen 96 (MD2), which allow it to better bind LPS. Once LPS has bound to the complex, it activates signalling to the toll/interleukin-1 receptor domain-containing adaptor protein (TIRAP) and Toll-interacting protein (TOLLIP), which then recruit MyD99 and IRAK1 to the TLR on the cell surface.Other TLRs have slightly more simple pathways, including TLR9, which recognizes CpG-DNA, which is a section of DNA with a cytosine followed by a guanine and are found commonly in pathogen genomes. TLRs 3 and 8 both recognize double stranded RNA, which is found in some viruses. TLR7 recognizes single stranded RNA from internalized viral genomes, and can also be activated by the drug Imiquimod, sold as Aldara. Imiquimod is used to treat genital warts , actinic keratosis and basal cell carcinoma by activating the immune system in the area it was applied. Finally, TLR5 recognizes the bacterial flagellin proteins. When any of these substances bind their respective TLRs, the TLRs signal to the MyD88 and IRAK1 complex.After any of these activation mechanisms occurs, the IRAK protein, which is a kinase, phosphorylates  and activates TNF receptor-associated factor 6 (TRAF6). TRAF6 then interacts with the evolutionarily conserved signaling intermediate in Toll pathway (ECSIT). ECSIT then activates mitogen-activated protein kinase kinase kinase 1 (MAP3K1). This then phosphorylates the IKK complex, comprised of inhibitors of nuclear factor kappa-B kinase subunits alpha and beta (IKKA and IKKB), as well as its regulatory subunit, NF-kappa-B essential modulator (NEMO). Another pathway starting with the activation of TRAF6 leads to this same point. First, TRAF6 activates a complex consisting of mitogen-activated protein kinase kinase kinase 7 (MAP3K7), as well as TGF-beta-activated kinase 1 (TAK1) and MAP3K7-binding proteins 1, 2 and 3. This complex can then activate dual specificity mitogen-activated protein kinase kinase 4 (MAP2K4), which then phosphorylates mitogen-activated protein kinase 8 (MAPK8) in the cell nucleus. Alternately, the TAK1 and MAP3K7-binding complex can phosphorylate and activate mitogen-activated protein kinase 14 (MAPK14), which then phosphorylates the IKK complex. NF-kappa-B is a transcription factor that is inhibited by NF-kappa-B inhibitor alpha, which binds to it and blocks its nuclear localization sequence, holding it in the cytoplasm rather than allowing it to enter the nucleus and transcribe the DNA. However, the IKK complex is able to phosphorylate the inhibitor, removing it and allowing nuclear factor NF-kappa-B p105 subunit and transcription factor p65 to enter the nucleus to transcribe DNA and allow the appropriate immune response for the stimulus to be activated."
What is the definition of EPO Signaling Pathway?,"The hormone erythropoietin, is a 166 amino acid protein with an apparent molecular weight in  its native form of 39,000 Da. The molecule is heavily glycosylated since its mass derived from its amino acid content is 18,398. The selective interaction of a hormone with its target cells is usually mediated by cell membrane receptors specific for the particular hormone. Erythropoietin-responsive cells have a trypsin-sensitive receptor for the hormone which requires protein synthesis for its maintenance. Erythropoietin-responsive cells can interact with other hematopoietic growth factors, and such interactions may lead to competition for pathway-specific differentiation, particularly under conditions of high cell density. The amino-terminal region of the hormone is not involved in receptor binding."
What is the definition of FAS signaling pathway ( CD95 )?,"Fas ligand is a transmembrane protein part of the tumor necrosis factor (TNF) family. It plays a role in inducing apoptosis and is an important regulator of the immune system. Fas ligand signals through the Fas receptor on target cells. Fas ligand binds to the receptor and forms the death-inducing signalling complex, including the Fas-associated death domain, death-domain associated protein, and caspase-10. Caspases are synthesized as inactive pro-caspases. Caspases are are proteases that cleave their substrates. Caspase-8 is an initiator caspase that is activated in response to pro-apoptotic stimulus and causes a cascade of further caspase activity by cleaving and activating effector caspases, like caspases -3 and -7.  Once activated, caspases -3 and -7 cleave downstream proteins. Caspase-8 activity is regulated by CASP8 and FADD-like apoptosis regulator. Kinases activate mitogen-activated protein kinases which activate pro-apoptotic JNK activity."
What is the definition of BCR Signaling Pathway?,"The BCR signalling pathway is a pathway that plays a vital role in the development and all other functions of B-cells, which means it is vital for the immune response. The BCR, also known as the B-cell receptor, is usually found on the outer membrane of B-cells. B-cells grab antigens from immune synapses, through a number of processes including cell spreading and receptor transport. After these have been performed, endocytosis and antigen-presentation occur. B-cells manipulate the dynamic of BCR-antigen bonds. They group and spread the antigen, increasing the relation with BCR, which creates sensitivity. The two main functions of the BCR pathway is to signal transduction, and the second is to prepare the antigen for processing by the helper T cells. Any defects in this pathway may lead to the patient being immunodeficient, or having B-cell malignancy. "
What is the definition of Cholesterol Biosynthesis and Metabolism?,"The biosynthesis of Cholesterol starts with acetyl-CoA reacts with acetyl-CoA c-acetyltransferase resulting in the release of CoA acetoacetyl-CoA, The latter compound then reacts with an acetyl-coa through a hydroxymethylglutaryl-CoA synthase resulting in the release of 3-hydroxy-3-methylglutaryl-CoA. The latter compound in turn reacts with a NADPH through a 3-hydroxy-3-methylglutaryl-coenzyme A reductase resulting in the release of a NADP, Coenzyme A and Mevalonic acid. The latter is then phosphorylated by ATP through a mevalonate kinase resulting in the release of ADP and Mevalonic acid-5P which is then phosphorylated by ATP through a phosphomevalonate kinase resulting in the release of ADP and (S)-5-diphosphomevalonic acid. The latter compound in turn reacts with ATP through a diphosphomevalonic decarboxylase resulting in the release of phosphate, ADP, carbon dioxide and Isopentenyl pyrophosphate. The latter compound in turn reacts with isopentenyl diphosphate delta isomerase resulting in the release of dimethylallylpyrophosphate. The latter compound then reacts with isopentenyl pyrophosphate through a farnesyl pyrophosphate synthase resulting in the release of Geranyl-PP. The latter then reacts with an isopentenyl pyrophosphate through farnesyl pyrophosphate synthase resulting in the release of pyrophospate and farnesyl pyrophosphate. Farnesyl pyrophosphate then reacts with NADPH through a squalene synthase in order to produce squalene while also releasing two phosphates and NADP. Squalene then reacts with oxygen and NADPH through a squalene monooxygenase resulting in the release of water, NADP and (S)-2,3-epoxysqualene. The latter in turn reacts with lanosterol synthase resulting in the release of lanosterin. Lanosterin then reacts with oxygen and NADPH through a lanosterol 14-alpha demethylase resulting in the release of formic acid, water, NADP and 4,4-dimethylcholesta-8,14,24-trienol. The latter compound in turn is reduced by an NADPH through a Delta (14)-sterol reductase resulting in the release of NADP and 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. The latter reacts with hydrogen ion,oxygen and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-hydroxymethyl-4B-methyl-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with a hydrogen ion, water, and NADPH through a methylsterol monooxygenase resulting in the release of NADP, water and 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen, NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4B-methyl-4a-carboxy-cholesta-8,24-dien-3B-ol. The latter reacts with an NADP through c-3 sterol dehydrogenase resulting in the release of NADPH, carbon dioxide and 3-keto-4-methylzymosterol. The latter is reduced by NADPH through a 3-keto sterol reductase resulting in the release of NADP and 4a-methylzymosterol. The latter then reacts with hydrogen, oxygen and nadph through methylsterol monooxygenase resulting in the release of water, NADP and 4a-hydroxymethyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with water, hydrogen and NADPH through a methylsterol monooxygenase resulting in the release of water, NADP and 4a-formyl-5a-cholesta-8,24-dien-3B-ol. The latter reacts with oxygen and NADPH through methylsterol monooxygenase resulting in the release of water, NADP and 4a-carboxy-5a-cholesta-8,24-dien-3B-ol. The latter compound reacts with NADP through a C-3 sterol dehydrogenase resulting in the release of carbon dioxide, NADPH and 5a-cholesta-8,24-dien-3-one. The latter reacts with hydrogen ion and NADPH through a 3-keto sterol reductase resulting in the release of NADP and zymosterol. Zymosterol can either be used to create ergosterol starts with zymosterol reacting with S-adenosylmethionine through a sterol 24-c-methyltransferase resulting in the release of S-adenosylhomocysteine, hydrogen ion and fecosterol. Fecosterol reacts with C-8 sterol isomerase resulting in the release of episterol. Episterol reacts with oxygen, hydrogen ion and ferrocytochrome c through a C-5 sterol desaturase resulting in the release of ferricytochrome c, water and 5,7,24(28)-ergostatrienol. The latter reacts with hydrogen ion, oxygen, NADPH and c-22 sterol desaturase resulting in the release of water, NADP AND ERGOSTA-5,7,22,24(28)-tetraen-3-B-ol. The latter compound reacts with hydrogen ion and NADPH through a C-24 sterol reductase resulting in the release of NADP and ergosterol. Zymosterol reacts with C-8 sterol isomerase resulting in the release of 5a-cholesta-7,24-dien-3b-ol. The latter compound reacts with C-5 sterol desaturase resulting in the release of 7-dehydrodesmosterol. The latter is then converted spontaneously through desmosterol. Desmosterol is then spontaneously turned into cholesterol which can, in turn, react with an acyl-CoA spontaneously resulting in the release of coenzyme A and a cholesteryl ester."
What is the definition of Phosphatidylethanolamine Biosynthesis PE(14:0/14:0)?,"Phosphatidylethanolamines (PE) are a class of phospholipids that incorporate a phosphoric acid headgroup into a diacylglycerol backbone. They are the second most abundant phospholipid in eukaryotic cell membranes, and contrary to phosphatidylcholine, it is concentrated with phosphatidylserine in the cell membrane's inner leaflet. In the visualization, all enzymes that are dark green in colour are membrane-localized. The first pathway synthesizes phosphatidylethanolamine from ethanolamine via the Kennedy pathway. First, the cytosol-localized enzyme choline/ethanolamine kinase catalyzes the conversion of choline into phosphocholine. Second, choline-phosphate cytidylyltransferase, localized to the endoplasmic reticulum membrane, catalyzes the conversion of phosphocholine to CDP-choline. Last, choline/ethanolaminephosphotransferase catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors. Phosphatidylethanolamine is also synthesized from phosphatidylserine at the mitochondrial inner membrane by phosphatidylserine decarboxylase. Phosphatidylserine, itself, is synthesized using a base-exchange reaction with phosphatidylcholine. This reaction is catalyzed by phosphatidylserine synthase which is located in the endoplasmic reticulum membrane."
What is the definition of Phosphatidylethanolamine Biosynthesis PE(16:0/16:0)?,"Phosphatidylethanolamines (PE) are a class of phospholipids that incorporate a phosphoric acid headgroup into a diacylglycerol backbone. They are the second most abundant phospholipid in eukaryotic cell membranes, and contrary to phosphatidylcholine, it is concentrated with phosphatidylserine in the cell membrane's inner leaflet. In Arabidopsis thaliana, there exist two phosphatidylethanolamine biosynthesis pathways. The first pathway consists of mainly enzymes localized to either the cytosol or the cell membrane. Cell membrane-localized enzymes in this pathway are not drawn as such for clarity. Instead, they are indicated with a dark green colour and appear to be free floating in the cytosol. This first pathway begins with serine decarboxylase catalyzing the biosynthesis of ethanolamine from serine. It requires pyridoxal 5'-phosphate as a cofactor. Next, choline/ethanolamine kinase, localized to the cell membrane, catalyzes the conversion of ethanolamine to phosphoethanolamine. Then ethanolamine-phosphate cytidylyltransferase, localized to the mitochondria outer membrane, catalyzes the conversion of phosphoethanolamine to CDP-ethanolamine. Last, choline/ethanolaminephosphotransferase, localized to the cell membrane, catalyzes phosphatidylethanolamine CDP-ethanolamine, respectively. The second pathway consists of mainly enzymes localized to the endoplasmic reticulum membrane (also depicted in dark green in the image. Beginning in the cytosol, glycerol-3-phosphate dehydrogenase [NAD(+)] catalyzes the interconversion of glycerone phosphate (from glycolysis) and glycerol 3-phosphate. After glycerol 3-phosphate enters the endoplasmic reticulum, glycerol-3-phosphate acyltransferase esterifies the acyl-group from acyl-CoA to the sn-1 position of glycerol-3-phosphate. Third, 1-acyl-sn-glycerol-3-phosphate acyltransferase 2 catalyzes the conversion of lysophosphatidic acid (LPA or 1-acyl-sn-glycerol 3-phosphate) into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by incorporating an acyl moiety at the 2nd position. Fourth, phosphatidate cytidylyltransferase catalyzes the conversion of a 1,2-diacyl-sn-glycerol 3-phosphate into a CDP-diacylglycerol. It requires a magnesium ion as a cofactor. Fifth, CDP-diacylglycerol--serine O-phosphatidyltransferase catalyzes the synthesis of phosphatidylserine from L-serine and a CDP-diacylglycerol. Last, phosphatidylserine decarboxylase catalyzes the formation of phosphatidylethanolamine from phosphatidylserine. It requires pyruvate as a cofactor."
What is the definition of Cardiolipin Biosynthesis?,"Cardiolipin (CL) is an important component of the inner mitochondrial membrane, and it is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the chloroplastic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor."
What is the definition of Succinate Signalling?,"Tricarboxylic acid (TCA) cycle intermediates can function as inflammatory signals. Succinate enhances glycolysis in several ways. It inhibits prolyl hydroxylase domain (PHD) enzyme function, both directly by product inhibition and indirectly via reactive oxygen species (ROS), driving hypoxia-inducible factor-1α (HIF-1α) accumulation and increased glycolysis. ROS also inhibit mitochondrial function, boosting glycolysis as a result. Elevated HIF-1α enhances the expression of genes containing HIF response elements (HREs), including the interleukin 1β (IL-1β) gene. Succinate can signal through succinate receptor 1 (SUCNR1) and act in synergy with Toll-like receptors (TLRs) to boost dendritic cell function. NAD+ exerts several anti-inflammatory effects by activating sirtuins, a class of NAD+-dependent deacetylases. Finally, inactivation of Sirt3 has been demonstrated to enhance NLR family, pyrin domain containing 3 (NLRP3) inflammasome activation."
What is the definition of NAD+ Signalling Pathway (Cancer)?,"NAD+-dependent signalling pathways regulate many fundamental processes such as DNA repair, DNA transcription, cell proliferation, cell survival, cell cycle progression, apoptosis, and metabolism. These pathways are all linked to cancer development. Degradation of NAD will activate various biosynthetic pathways, which are crucial for incessant cancer cell proliferation. "
What is the definition of NAD+ Signalling and Aging?,"An interesting link has emerged between NAD+ metabolism, SIRT1, SIRT3, and mitochondrial function. NR and PARP inhibitors increased life span in worms via activation of the mitochondrial unfolded protein response UPRmt by sir2.1. Short-term (1 week) supplementation of these mice with NMN restored mitochondrial homeostasis in muscles, which suggests that NAD+ supplementation can restore some reversible aspects of the aging process. Both observations are consistent with the model indicating that an imbalance in the relative stoichiometries of mitochondria- versus nucleus-encoded ETC proteins may induce life-span extension via activation of the UPRmt. In support of such a mechanism, mutation or reduced function in nuclear genes encoding ETC components in yeast, Caenorhabditis elegans, Drosophila, and mice increase life span through activation of the mitochondrial unfolded protein response UPRmt. NAD salvage pathway is deficient in aging since the supplementation with NMN corrects defects associated with aging."
What is the definition of Succinate Signalling During Inflammation?,"Succinate induces calcium mobilization in an adenylyl cyclase (AC) and protein kinase A (PKA)-dependent manner. Succinate receptor 1 (SUCNR1) engagement activates phospholipase C (PLC), resulting in the cleavage of phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol trisphosphate (IP3) and diacylglycerol (DAG). These second messengers induce calcium mobilization and PKC activation, respectively, and subsequent nitric oxide (NO) and prostaglandin E2 (PGE2) production as well as p38 activation. PKC-dependent phosphorylation of extracellular signal-related kinases ERK1/2 can also drive PG production. SUCNR1 signaling might act in synergy with several inflammatory signaling cascades. PKA is known to phosphorylate and activate the p65 subunit of nuclear factor κB (NF-κB) and cAMP response element-binding protein (CREB). Furthermore, NF-κB, activating protein (AP)-1, nuclear factor of activated T cells (NFAT), and ETS domain-containing protein (Elk-1) are all downstream targets of PKC and MAPKs."
What is the definition of De Novo Triacylglycerol Biosynthesis TG(14:0/14:0/14:0)?,"A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and other animals, as well as vegetable fat (Wikipedia). De novo biosynthesis of triglycerides is also known as the phosphatidic acid pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytoplasmic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). The next three steps are localized to the endoplasmic reticulum membrane. The enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. Next, phosphatidate phosphatase catalyzes the conversion of phosphatidic acid into diacylglycerol. Last, the enzyme diacylglycerol O-acyltransferase synthesizes triacylglycerol from diacylglycerol and a fatty acyl-CoA."
What is the definition of Bile Acid Direct Signalling Pathway (1)?,"Bile acids are synthesized in the liver and stored in the gallbladder. After eating, bile acids are released from the gallbladder into the small intestine. The majority of bile acids are transported back to the liver, but some may then escape enterohepatic circulation to enter systemic circulation. The bile acids, deoxycholic acid (DCA) and chenodeoxy cholic acid (CDCA), may interact with gap junction proteins to cross the blood-brain barrier. Bile acids are endogenous ligands for farnesoid X receptor (FXR) and G-protein coupled BA receptor 1 (TGR5) and once they have crossed the blood brain barrier, the bile acids may interact with these receptors. FXR is a regulator of secretion and transport of bile acids. TGR5 receptor activation increases cAMP synthesis and activates the mitogen-activated protein kinase (MAPK) pathway. TGR5 regulates the use of energy and is a target of interest for metabolic disorders. "
What is the definition of Bile Acid Indirect Signalling Pathway?,"Bile acids are taken up by enterocytes, epithelial cells of the small intestine, where they can activate the nuclear receptor farnesoid X receptor (FXR). This causes the production of fibroblast growth factor 19 (FGF19) which is then transported out of the enterocyte to the portal vein. While most FGF19 goes to the liver, some FGF19 instead enters systemic circulation where it can cross the blood brain barrier and interact with its receptors in the brain. Beta-klotho is a transmembrane protein that promotes the interaction of FGF19 and the receptor to form a stable complex. FGF receptor signaling likely plays a role in energy and glucose metabolism. "
What is the definition of Bile Acid Direct Signalling Pathway (2) ?,"In the intestine, L-cells (enteroendocrine cells) can produce glucagon-like peptide 1 (GLP-1) after bile acid activates G-protein coupled bile acid receptor 1 on L-cells. Only small portion of GLP-1 can enter the systemic cirulation, and most of GLP-1 are degraded by dipeptidyl peptidase-4. Therefore, only small portion of GLP-1 can eventually across blood-brain barrier to interact with GLP-1 receptors "
What is the definition of CD40L Signalling Pathway?,"CD40 is a part of the tumor necrosis factor (TNF) receptor superfamily. When bound to it’s main ligand CD40L, also known as CD154, CD40-CD40L interaction initializes the activation and proliferation of B lymphocytes or results in carcinoma cells apoptosis.CD40 can be expressed on many different cell surfaces such as endothelial cells, fibroblasts, hematopoietic progenitors, platelets, and basal epithelial cells. When combined with the variety of environments CD40 presenting cells can be in, the differing effects resulting from CD40 signalling is vast. However, one characteristic all CD40 mediated signalling has in common is that instead of using kinase to mediate signal transduction, signalling is performed through downstream adapter molecules. Some pathways activated by CD40-CD40L signalling include the activation of nuclear factor-κB, p38 mitogen activated protein kinase, c-Jun-NH2-kinase, signal transducers and activators of transcription, and phosphoinositide 3-kinase pathways. All of which ultimately help regulate alterations in gene expression."
What is the definition of G-Protein Signaling Through Tubby Proteins?,"Tubby protein is a part of a family of proteins called Tubby Like Proteins (TULP) characterized by 260 amino acids that form a helix-filled barrel structure at the carboxylic acid terminal (Tubby domain). Using its Tubby domain to bind phosphatidylinositol 4,5-bisphosphate (PIP2), Tubby proteins are able to localize on the plasma membrane. Through the receptor mediated activation of G-proteins, the enzyme phospholipase C–beta (PLC-beta) hydrolyses PIP2 releasing tubby from the plasma membrane. This triggers protein translocation of tubby to the nucleus allowing tubby to act as a transcription regulator. "
What is the definition of g-Secretase Mediated ErbB4 Signalling Pathway?,"The HER4/erbB4-encoded protein, is a transmembrane receptor that contains a cytoplasmic tyrosine kinase domain. This domain exhibits almost 80 percent homologness with the corresponding domain of EGFR (the epidermal growth factor receptor). It was discovered in the 1990s by Plowman et al, that heregulin was responsible for inducing tyrosine phosphorylation of HER4/erbB4. ErbB4 (HER4) receptor is classified as type I GFRs. Where the tyrosine kinase growth factor receptors (GFRs) have been sub-classified into 9 different families based on the structure of their extracellular ligand binding and intracellular kinase domains and the manner in which such protein induce the ligands. Experiments revealed that erbB4 has is readily findable in heart, spleen, breast, muscle, pituitary, kidney, parathyroid, brain, and testis. "
What is the definition of Ion Channel and Phorbal Esters Signaling Pathway?,"Molecules transmitting signals into cells often act through receptors in the plasma membrane that stimulate production of second messengers. When activated by a plasma membrane receptor, the enzyme phospholipase C (PLCg) hydrolyzes the membrane lipid phosphatidylinositol (PIP2) into the second messengers diacylglycerol (DAG) and IP3. IP3 releases calcium from intracellular stores into the cytoplasm where calcium alters many cellular activities, including activating protein kinase C. DAG also activates protein kinase C. Biologists often study signaling by artificially manipulating pathways using molecules like ionomycin and phorbol esters as research tools. Ionomycin is a molecule that carries calcium through the plasma membrane to increase the calcium concentration in the cytoplasm and activate protein kinase C without activating phospholipase C. Phorbol esters are molecules that mimic the action of DAG in the activation of protein kinase C, and were originally identified as tumor-promoting agents. The combination of ionomycin and phorbol esters is often used experimentally to study the effect of calcium and DAG signaling in cellular responses like T cell activation."
What is the definition of Circadian Rhythms?,"The nuclear entry of clock gene products is required to establish the negative feed back loop- a key step in proper circadian rhythm. Heterodimerization of clock proteins PER and CRY is required for translocation to the nucleus. Nuclear entry of PER can be regulated by mammalian casein kinase I (CK1). Once in the nucleus, PER and CRY proteins appear to differentially inhibit the transactivation by CLOCK/BMAL1. Proteins like REV-ERBa and DEC also regulate the transcriptional activation by CLOCK/BMAL1. In addition, CRY, PER, and BMAL1-CLOCK play bidirectional roles in transcription resulting in interactivating feedback loops. The expression of BMAL1 and CLOCK can be upregulated by CRY and PER. Such loops are believed to be important in the stability and persistence of circadian rhythm."
What is the definition of Hop Pathway in Cardiac Development?,"Homeodomain transcription factors comprise a large family of DNA binding factors that regulate transcription and development. Many homeodomain genes arranged in genomic clusters determine anterior-posterior patterning, while others determine the fate of cells in specific tissues. The proliferation of cardiac myocytes and their differentiation early in development are both dependent on the coordinate expression and action of serum response factor (SRF), GATA4 and the homeodomain factor Nkx2-5. All three of these factors are expressed in developing cardiomyocytes and induce expression of cardiac genes. Disruption of the Nkx2-5 gene in mice leads to embryonic lethality and defective cardiac development. SRF also plays a duel role in cardiac development, influencing both cardiomyocyte proliferation and differentiation depending on the stage and other signals that are present.In addition, the Hop (Homeodomain Only Protein) gene encodes a factor expressed early in cardiac development that is involved in cardiac differentiation. Hop inactivation in vertebrates leads to severe defects in cardiac development, acting downstream of Nkx2-5. Cardiac cells from mice lacking the Hop gene fail to exit the cell cycle in the normal manner, continuing to proliferate past the normal developmental stage. Many of the genes disregulated in the absence of Hop are involved in the cell cycle and are also targets of SRF. Although Hop is a homeodomain protein, it lacks a DNA-binding domain indicating that it must not regulate gene expression directly. Hop appears to regulate the expression of cardiac genes by binding to SRF and blocking DNA binding of SRF. The sequestration of SRF by Hop blocks the activation of cardiac genes, preventing normal cardiac development. The influence of Hop on the opposing processes of cardiomyocyte differentation and proliferation reflect the interaction of Hop with SRF and the duel role SRF plays. In early cardiac development, Hop opposes differentiation induction by SRF, while at later stages Hop opposes the proliferation induced by SRF."
What is the definition of Chitin Biosynthesis?,"Chitin is a linear homopolymer of N-acetyl-β-D-glucosamine residues linked by β-1,4 glycosidic bonds to form microfibrils.  These become the structural component to cell walls and many extracellular matrices such as cuticles and exoskeleton of insects. This process is highly conserved and occurs in many different organisms including insects and fungi. Chitin exist in several crystaline forms termed α, β and γ chitin, the most abundant being α chitin (reviewed in [Merzendorfer11]). Chitin and lipids are secreted by epidermal cells and form the basis for the cuticle material and layered structure."
What is the definition of LPS and Citrate Signaling and Inflammation?,"Citrate is an important substrate in cellular energy metabolism, which is produced by mitochondria and used in Krebs cycle or released into cytoplasm through a specific mitochondrial carrier, CIC. In the cytosol, citrate and its derivatives, acetyl-CoA and oxaloacetate, are used in normal and pathological processes. Apart from the classical role as metabolic regulator, citrate is also involved in inflammation, cancer, insulin secretion, histone acetylation, neurological disorders and non-alcoholic fatty lever disease. "
What is the definition of Phosphatidylcholine/Phosphatidylethanolamine Biosynthesis?,"Phosphatidylcholines (PC) are a class of phospholipids that incorporate a phosphocholine headgroup into a diacylglycerol backbone. They are the most abundant phospholipid in eukaryotic cell membranes and has both structural and signalling roles. In eukaryotes, there exist two phosphatidylcholine biosynthesis pathways: the Kennedy pathway and the methylation pathway. The Kennedy pathway begins with the direct phosphorylation of free choline into phosphocholine followed by conversion into CDP-choline and subsequently phosphatidylcholine. It is the major synthesis route in animals. In the visualization, all enzymes that are dark green in colour are membrane-localized. The first reaction of the Kennedy pathway involves the cytosol-localized enzyme choline/ethanolamine kinase catalyzing the conversion of choline into phosphocholine. Second, choline-phosphate cytidylyltransferase, localized to the endoplasmic reticulum membrane, catalyzes the conversion of phosphocholine to CDP-choline. Last, choline/ethanolaminephosphotransferase catalyzes phosphatidylcholine biosynthesis from CDP-choline. A parallel Kennedy pathway forms phosphatidylethanolamine from ethanolamine. Phosphatidylethanolamines (PE) are a class of phospholipids that incorporate a phosphoric acid headgroup into a diacylglycerol backbone. They are the second most abundant phospholipid in eukaryotic cell membranes, and contrary to phosphatidylcholine, they are concentrated with phosphatidylserine in the cell membrane's inner leaflet. Phosphatidylethanolamine is also synthesized from phosphatidylserine at the mitochondrial inner membrane by phosphatidylserine decarboxylase. Phosphatidylserine, itself, is synthesized using a base-exchange reaction with phosphatidylcholine. This reaction is catalyzed by phosphatidylserine synthase which is located in the endoplasmic reticulum membrane."
What is the definition of Phosphatidylcholine/Phosphatidylethanolamine Biosynthesis PC(14:0/14:0) | PE(14:0/14:0)?,"Phosphatidylcholines (PC) are a class of phospholipids that incorporate a phosphocholine headgroup into a diacylglycerol backbone. They are the most abundant phospholipid in eukaryotic cell membranes and has both structural and signalling roles. In eukaryotes, there exist two phosphatidylcholine biosynthesis pathways: the Kennedy pathway and the methylation pathway. The Kennedy pathway begins with the direct phosphorylation of free choline into phosphocholine followed by conversion into CDP-choline and subsequently phosphatidylcholine. It is the major synthesis route in animals. In the visualization, all enzymes that are dark green in colour are membrane-localized. The first reaction of the Kennedy pathway involves the cytosol-localized enzyme choline/ethanolamine kinase catalyzing the conversion of choline into phosphocholine. Second, choline-phosphate cytidylyltransferase, localized to the endoplasmic reticulum membrane, catalyzes the conversion of phosphocholine to CDP-choline. Last, choline/ethanolaminephosphotransferase catalyzes phosphatidylcholine biosynthesis from CDP-choline. It requires either magnesium or manganese ions as cofactors. A parallel Kennedy pathway forms phosphatidylethanolamine from ethanolamine. Phosphatidylethanolamines (PE) are a class of phospholipids that incorporate a phosphoric acid headgroup into a diacylglycerol backbone. They are the second most abundant phospholipid in eukaryotic cell membranes, and contrary to phosphatidylcholine, they are concentrated with phosphatidylserine in the cell membrane's inner leaflet. Phosphatidylethanolamine is also synthesized from phosphatidylserine at the mitochondrial inner membrane by phosphatidylserine decarboxylase. Phosphatidylserine, itself, is synthesized using a base-exchange reaction with phosphatidylcholine. This reaction is catalyzed by phosphatidylserine synthase which is located in the endoplasmic reticulum membrane."
What is the definition of Protein Synthesis: Alanine?,"Protein synthesis is an essential life process that builds the important large amino acid macromolecules that function as enzymes, antibodies, and cellular structural components. Although synthesis begins with the transcription of DNA into RNA, this pathway depicts the reactions that occur during translation. Transcribed messenger RNA (mRNA), which contains the genetic code to direct protein synthesis, is transported out of the nucleus and becomes bound to ribosomes in the cytoplasm or endoplasmic reticulum. The amino acids required to assemble polypeptide chains are delivered to the ribosomes using transfer RNA (tRNA). Each tRNA molecule has both a binding site for a specific amino acid and a three-nucleotide sequence called the anticodon that forms three complementary base pairs with an mRNA codon. Charging or loading the appropriate amino acid onto its tRNA is carried out by an aminoacyl-tRNA synthetase (aaRS or ARS), also called tRNA-ligase. This enzyme catalyzes the esterification of an amino acid to one of all its compatible tRNAs to form an aminoacyl-tRNA. Each of the twenty amino acids has a corresponding aa-tRNA made by a specific aminoacyl-tRNA synthetase. Ribosomes match the anticodons of the charged tRNA molecules with successive codons of the mRNA. After a match is found, the ribosome transfers the amino acid from the matching tRNA onto the growing peptide chain via a reaction termed peptide condensation, and the tRNAs, no longer carrying amino acids, are released."
What is the definition of Kidney Function?,"Kidneys are regulatory organs involved in removing wastes from the blood, hormone production, nutrient reabsorption, and regulating electrolyte concentrations, acid-base balance, extracellular fluid volume, and blood pressure. The early proximal tubule is where glucose, amino acids, sodium, chlorine, phosphate, bicarbonate, and water are reabsorbed. Only water is reabsorbed in the thin descending loop of Henle, while sodium, chlorine and potassium are reabsorbed in the thick ascending loop of Henle. Sodium and chlorine are also reabsorbed in the early distal convoluted tubule. Finally, sodium and water are reabsorbed in the collecting tubules. Blood pressure is regulated by the hormones angiotensin II and aldosterone, which increases sodium chloride reabsorption. This results in an expansion of the extracellular fluid compartment, thus increasing blood pressure."
What is the definition of Pancreas Function?,"The pancreas is crucial in many organisms for properly converting food into usable fuel to be used by cells. It acts as part of the digestive system for a majority of its function as it is connected to the stomach and provides digestive enzymes to the partly digested food brought in by the stomach. The pancreas also serves as an endocrine component, by creating hormones to regulate blood sugar. Insulin, a hormone created by the pancreas, acts to lower blood sugar, which is very important as it allows cells in the body to use sugar without inducing hyperglycaemia. "
What is the definition of Kidney Function- Proximal Convoluted Tubule?,"The proximal convoluted tubule is part of the nephron between the Bowman's capsule and the loop of Henle. The proximal convoluted tubule functions to reabsorb sodium, water, and other ions. Sodium and bicarbonate (hydrogen carbonate) are transported by a co-transporter that is responsible for the majority of sodium reabsorption. The bicarbonate, along with hydrogen, are exchanged across the basal and apical membranes, respectively, to effectively regulate the pH of the filtrate.  In addition, chloride ions are not normally reabsorbed in large amounts at the proximal tubule compared to other parts of the nephron.  However, the reabsorption of chloride, as well as potassium, increases as the amount of water reabsorption increases due to solvent drag (also known as bulk transport).  This occurrence explains solute movement secondary to water flow.  All the cation and anion transport creates a gradient favourable for ion and water reabsorption, leading to an increase in blood pressure. "
What is the definition of Kidney Function - Descending Limb of the Loop of Henle?,"The loop of Henle of the nephron can be separated into an ascending limb and the descending limb.  The ascending limb is highly impermeable to water, but permeable to solutes.  Conversely, the descending limb is highly impermeable to solutes such as sodium, but permeable to water.  As solutes are being actively transported out of the ascending limb, the solutes cause in increase in osmotic pressure.  This, combined with the ability for water to move freely out of the descending limb, leads to a water reabsorption into the adjacent capillary network and a high concentration of sodium in the filtrate at the descending Limb.  Water moves from the descending loop to the capillary network through aquaporin channels in the cell membrane."
What is the definition of Kidney Function - Ascending Limb of The Loop of Henle?,"The loop of Henle of the nephron can be separated into an ascending limb and the descending limb.  The descending limb is highly impermeable to solutes such as sodium, but permeable to water.  Conversely, the ascending limb is highly impermeable to water, but permeable to solutes. Chloride, potassium, and sodium are co-transported across the apical membrane (closest to the lumen) via transporters from the filtrate. The transporter requires all three ions present to be effective and to maintain electroneutrality. In addition, the three ions are transported across the basolateral membrane (closest to the renal interstitium) via other means such as the sodium potassium ATPase transports and the chloride channels in the membrane. As these solutes are being actively transported out of the ascending limb and into the renal interstitium/capillary network without water following (due to the lack of water permeability), the filtrate becomes more diluted. Furthermore, these ions simultaneously causes an increase in osmotic pressure that contributes to water reabsorption in the descending limb.  This effect can be magnified with the help of vasopressin, which is a hormone that is typically involved with water reabsorption.  However, when it acts on the ascending limb, it aids in increasing sodium reabsorption which will increase water reabsorption in the latter parts of the nephron (the distal tubule and collecting duct)."
What is the definition of Kidney Function - Collecting Duct?,"The collecting duct of the nephron is the last segment of the functioning nephron and is connected to minor calyces and the ensuing renal pelvis of the kidney where urine continues before it is stored in the bladder.  The collecting duct is mainly responsible for the excretion and reabsorption of water and ions. It is composed of two important cell types: intercalated cells that are responsible for maintaining acid-base homeostasis, and principal cells that help maintain the body's water and salt balance.  When renin is released from the kidneys, it causes the activation of angiotensin I in the blood circulation which is cleaved to become angiotensin II. Angiotensin II stimulates the release of aldosterone from the adrenal cortex and release of vasopressin from the posterior pituitary gland.  When in the circulation, vasopressin eventually binds to receptors on epithelial cells in the collecting ducts.  This causes vesicles that contain aquaporins to fuse with the plasma membrane.  Aquaporins are proteins that act as water channels once they have bound to the plasma membrane.  As a result, the permeability of the collecting duct changes to allow for water reabsorption back into the blood circulation.  In addition, sodium and potassium are also reabsorbed back into the systemic circulation at the collecting duct via potassium and sodium channels. However, aldosterone is a major regulator of the reabsorption of these ions as well, as it changes the permeability of the collective duct to these ions.  As a result, a high concentration of sodium and potassium in the blood vessels occurs. Some urea and other ions may be reabsorbed as well. The reabsorption of ions and water increases blood fluid volume and blood pressure. "
What is the definition of Kidney Function - Distal Convoluted Tubule?,"The distal convoluted tubule of the nephron is the part of the kidney between the loop of henle and the collecting duct. When renin is released from the kidneys, it causes the activation of angiotensin I in the blood circulation which is cleaved to become angiotensin II. Angiotensin II stimulates the release of aldosterone from the adrenal cortex and release of vasopressin from the posterior pituitary gland.  When in the circulation, vasopressin eventually binds to receptors on epithelial cells in the distal convoluted tubule.  This causes vesicles that contain aquaporins to fuse with the plasma membrane.  Aquaporins are proteins that act as water channels once they have bound to the plasma membrane.  As a result, the permeability of the distal convoluted tubule changes to allow for water reabsorption back into the blood circulation. In addition, sodium, chlorine, and calcium are also reabsorbed back into the systemic circulation via their respective channels and exchangers. However, aldosterone is a major regulator of the reabsorption of these ions as well, as it changes the permeability of the distal convoluted tubule to these ions.  As a result, a high concentration of sodium, chlorine, and calcium in the blood vessels occurs. The reabsorption of ions and water increases blood fluid volume and blood pressure. "
What is the definition of Pancreas Function - Beta Cell?,"Beta cells are found in pancreatic islet cells and their main function is to release insulin.  Insulin counteracts glucagon and functions to maintain glucose homeostasis when glucose levels are high.  Insulin is contained in granules in the cell as a reserve ready to be released, which is dependent on extracellular glucose levels, and intracellular calcium levels and/or various proteins that activate the vesicle-associated membrane protein on the insulin granules' membranes.  In the process of insulin secretion, glucose must first undergo glycolysis to increase ATP in the cell.  The inside of the beta cell then becomes electrically positive due to the closure of potassium channels that were inhibited by ATP.  From this closure, the potassium is no longer being shuttled out of the cell, thus depolarizing the cell due to the extra intracellular potassium.  The resulting action potential from the increased membrane potential causes the voltage gate calcium channels to open, creating an influx of calcium into the cell.  This triggers the vesicle-associated membrane protein on the outside of the insulin granule to tether, dock, and fuse with the beta cell membrane.  Insulin is then exocytosed from the cell.  However, the vesicle-associated membrane protein can be activated by other means in addition to calcium.  Acetylcholine can bind to muscarinic acetylcholine receptors on the cell membrane and trigger a G protein cascade.  This eventually leads to the activation of inositol trisphosphate to cause calcium release from the rough endoplasmic reticulum so that it can activate the calcium/calmodulin-dependent protein kinase to trigger the vesicle-associated membrane protein.  The G protein cascade can also lead to the activation of diacylglycerol and subsequently protein kinase C to lead to the same outcome.  Glucagon-like peptide can also trigger a similar G protein cascade when it binds to glucagon-like peptide receptors on the cell membrane of the beta cell.  This process involves cAMP and a few other proteins in order to lead to the same eventual outcome of triggering the vesicle-associated membrane protein and the exocytosis of insulin from the beta cell."
What is the definition of Pancreas Function - Alpha Cell?,"Alpha cells are a type of islet cell found in the pancreas that release glucagon. Glucagon counteracts insulin and functions to maintain glucose homeostasis when detected glucose levels are low. Glucagon is contained in granules in the cell as a reserve ready to be released. Extracellular glucose levels and ion channels regulate the secretion of glucagon.  Glucose undergoes glycolysis to increase ATP in the cell. The moderate activity of potassium ATP channels causes the membrane potential to be around -70mV. The alpha cell then becomes electrically active due to the closure of potassium channels. The cell membrane becomes depolarized due to voltage dependent sodium, potassium and calcium channels. This causes an increase in action potentials and opens voltage gate calcium channels causing an increase of calcium into the cell. This triggers the exocytosis of glucagon from the cell.  Conversely, an increase in extracellular glucose leads to an increase in ATP production and inhibition of potassium ATP channels. The membrane depolarizes to a membrane potential that inactivates voltage dependent calcium channels. This results in decreased intracellular calcium and inhibits exocytosis of glucagon. "
What is the definition of Mevalonate Pathway?,"The Mevalonate Pathway is a necessary pathway that occurs in archaea, eukaryotes and select bacteria. It has mainly been studied with regard to cholesterol biosynthesis and how it relates to cardiovascular disease in humans, but has recently garnered attention for its many other essential roles within human pathology.  The pathway begins in the cytoplasm with acetyl-CoA and acetoacetyl-CoA, which interact with acetyl-CoA acetyltransferase, coenzyme A and water to synthesize hydroxymethylglutaryl-CoA synthase. In turn, this synthase teams up with coenzyme A and a hydrogen ion in the endoplasmic reticulum to create 3-hydroxy-3-methylglutaryl-CoA. 3-Hydroxy-3-methylglutaryl-CoA then pairs with 2NADPH, 2 hydrogen ions and is catalyzed by 3-hydroxy-3-methylglutaryl-coenzyme A reductase to produce (R)-mevalonate, also producing byproducts CoA and NADP. Exiting the endoplasmic reticulum, and entering the peroxisome, (R)-mevalonate uses the help of ATP and mevalonate kinase to create mevalonic acid (5P). This piece is especially important to the human species as decreased activity of the enzyme mevalonate kinase has been found to be a direct link to two auto-inflammatory disorders: MVA and HIDS. Using phosphomevalonate kinase and ATP, the pathway re-enters the cytoplasm and mevalonic acid (5P) converts to (R)-mevalonic acid-5-pyrophosphate and ADP. (R)-mevalonic acid-5-pyrophosphate, ATP and diphosphomevalonate decarboxylase work together to create phosphate, carbon dioxide, ADP and isopentenyl pyrophosphate. Re-entering the peroxisome, isopentenyl diphosphate delta isomerase 1 is waiting to propel isopentenyl pyrophosphate into dimethylallylpyrophosphate. This pushes the pathway back into the cytoplasm, where another isopentenyl pyrophosphate molecule and the enzyme farnesyl pyrophosphate synthase create pyrophosphate and geranyl-PP. Yet another isopentenyl pyrophosphate molecules works with farnesyl pyrophosphate synthase to produce pyrophosphate and farnesyl pyrophosphate. Now in the endoplasmic reticulum membrane, 2 farnesyl pyrophosphate molecules with the help of NADPH and a hydrogen ion catalyze with squalene synthase and create squalene. This is an important first step in the specific hepatic cholesterol pathway. Remaining in the endoplasmic reticulum membrane, squalene, FMNH, oxygen and squalene monooxygenase synthesize (S)-2,3-epoxysqualene. This comes along with the byproducts of flavin mononucleotide, a hydrogen ion and water. In the final reaction within this pathway,  lanesterol synthase converts (S)-2,3-epoxysqualene to lanosterin. Not pictured in this pathway, lanosterin will eventually be converted to cholesterol, an important part of many functions in the human body. "
What is the definition of Bloch Pathway (Cholesterol Biosynthesis) ?,"The Bloch pathway, named after Konrad Bloch, is the pathway following the mevalonate pathway occurring within the cell to complete cholesterol biosynthesis. Cholesterol is a necessary metabolite that helps create many essential hormones within the human body. This pathway, combined with the mevalonate pathway is one of two ways to biosynthesize cholesterol; the Kandutsch-Russell pathway is an alternative pathway that uses different compounds than the Bloch Pathway beginning after lanosterol. The first three reactions occur in the endoplasmic reticulum. Lanosterol, a compound created through the mevalonate pathway, binds with the enzyme lanosterol 14-alpha demethylase to become 4,4-dimethyl-14a-hydroxymethyl-5a-cholesta-8,24-dien-3b-ol. Moving to the next reaction, 4,4-dimethyl-14a-hydroxymethyl-5a-cholesta-8,24-dien-3b-ol utilizes the enzyme lanosterol 14-alpha demethylase to create 4,4-dimethyl-14α-formyl-5α-cholesta-8,24-dien-3β-ol. Lanosterol 14-alpha demethylase is used one last time in this pathway, converting 4,4-dimethyl-14α-formyl-5α-cholesta-8,24-dien-3β-ol into 4,4-dimethyl-5a-cholesta-8,14,24-trien-3b-ol. Entering the inner nuclear membrane, 4,4-dimethyl-5a-cholesta-8,14,24-trien-3b-ol is catalyzed by a lamin B receptor to create 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. Entering the endoplasmic reticulum membrane, 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol, with the help of methyl monooxygenase 1 is converted to 4a-hydroxymethyl-4b-methyl-5a-cholesta-8,24-dien-3b-ol. The enzyme methyl monooxygenase 1 uses 4a-hydroxymethyl-4b-methyl-5a-cholesta-8,24-dien-3b-ol to produce 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3b-ol. This reaction is repeated once more, using 4a-formyl-4b-methyl-5a-cholesta-8,24-dien-3b-ol and methyl monooxygenase 1 to create 4a-carboxy-4b-methyl-5a-cholesta-8,24-dien-3b-ol. Briefly entering the endoplasmic reticulum, 4a-carboxy-4b-methyl-5a-cholesta-8,24-dien-3b-ol then uses sterol-4-alpha-carboxylate-3-dehyrogenase to catalyze into 3-keto-4-methylzymosterol. Back in the endoplasmic reticulum membrane, where the pathway will continue on for the remaining reactions, 3-keto-4-methylzymosterol combines with 3-keto-steroid reductase to create 4a-methylzymosterol. 4a-Methylzymosterol joins the enzyme methylsterol monooxgenase 1 to result in 4a-hydroxymethyl-5a-cholesta-8,24-dien-3b-ol. 4a-Hydroxymethyl-5a-cholesta-8,24-dien-3b-ol uses methylsterol monooxygenase 1 to convert to 4a-formyl-5a-cholesta-8,24-dien-3b-ol. 4a-Formyl-5a-cholesta-8,24-dien-3b-ol proceeds to use the same enzyme used in the previous reaction: methylsterol monooxygenase 1, to catalyze into 4a-carboxy-5a-cholesta-8,24-dien-3b-ol. Sterol-4-alpha-carboxylate-3-dehydrogenase is used alongside 4a-carboxy-5a-cholesta-8,24-dien-3b-ol to produce 5a-cholesta-8,24-dien-3-one (also known as zymosterone). Zymosterone (5a-cholesta-8,24-dien-3-one) teams up with 3-keto-steroid reductase to create zymosterol. Zymosterol proceeds to use the enzyme 3-beta-hydroxysteroid-delta(8),delta(7)-isomerase to catalyze into 5a-cholesta-7,24-dien-3b-ol. The compound 5a-cholesta-7,24-dien-3b-ol then joins lathosterol oxidase to convert to 7-dehydrodesmosterol. 7-Dehydrodesmosterol and the enzyme 7-dehydrocholesterol reductase come together to create desmosterol. This brings the pathway to the final reaction, where desmosterol combines with delta(24)-sterol reductase to finally convert to cholesterol. "
What is the definition of Kandutsch-Russell Pathway (Cholesterol Biosynthesis)?,"The Kandutsch-Russell pathway is the alternative pathway stemming from the mevalonate pathway completing cholesterol biosynthesis. The Bloch pathway and the Kandutsch-Russell pathway are both key to a functioning human body as cholesterol aids in the development of many important nutrients and hormones, such as vitamin D. Starting in the endoplasmic reticulum, lanosterol is the first compound used in this pathway, and when catalyzed by delta(24)-sterol-reductase, becomes 24,25-dihydrolanosterol. 24,25-Dihydrolanosterol is quickly converted to 4,4-dimethyl-14a-hydroxymethyl-5a-cholesta-8-en-3b-ol with the help of the enzyme lanosterol 14-alpha demethylase. This same enzyme, lanosterol 14-alpha demethylase, is also responsible for the conversion of 4,4-dimethyl-14a-hydroxymethyl-5a-cholesta-8-en-3b-ol into 4,4-dimethyl-14a-formyl-5a-cholest-8-en-3b-ol. Lanosterol 14alpha demethylase is used once more here, to push the pathway into the inner nuclear membrane, converting 4,4-dimethyl-14a-formyl-5a-cholest-8-en-3b-ol into 4,4-dimethyl-5a-cholesta-8,14-dien-3b-ol. Now located in the inner nuclear membrane, 4,4-dimethyl-5a-cholesta-8,14-dien-3b-ol is converted into 4,4-dimethyl-5a-cholesta-8-en-3b-ol through the help of a lamin-b receptor. Entering the endoplasmic reticulum membrane, methylsterol monooxygenase 1 is used to convert 4,4-dimethyl-5a-cholesta-8-en-3b-ol into 4a-hydroxymethyl-4b-methyl-5a-cholesta-8-en-3b-ol. 4a-Hydroxymethyl-4b-methyl-5a-cholesta-8-en-3b-ol then uses methylsterol monooxygenase 1 to become 4a-formyl-4b-methyl-5a-cholesta-8-en-3b-ol. Once again, methylsterol monooxygenase 1 is used to convert 4a-formyl-4b-methyl-5a-cholesta-8-en-3b-ol into 4a-carboxy-4b-methyl-5a-cholesta-8-en-3b-ol. Now using sterol-4-alpha-carboxylate 3-dehydrogenase, 4a-carboxy-4b-methyl-5a-cholesta-8-en-3b-ol is turned into 4a-methyl-5a-cholesta-8-en-3-one. This puts the pathway in the cell membrane, where a 3-keto-steroid reductase is used to convert 4a-methyl-5a-cholesta-8-en-3b-one into  4a-methyl-5a-cholesta-8-en-3-ol. Moving back into the endoplasmic reticulum membrane, methylsterol monooxygenase 1 converts 4a-methyl-5a-cholesta-8-en-3-ol into 4a-hydroxymethyl-5a-cholesta-8-en-3b-ol. Methylsterol monooxygenase is used twice more in this pathway, first converting 4a-hydroxymethyl-5a-cholesta-8-en-3b-ol into 4a-formyl-5a-cholesta-8-en-3b-ol, then converting 4a-formyl-5a-cholesta-8-en-3b-ol into 4a-carboxy-5a-cholesta-8-en-3b-ol. Now using sterol-4-alpha-carboxylate 3 dehydrogenase, 4a-carboxy-5a-cholesta-8-en-3b-ol becomes 5a-cholesta-8-en-3-one and brings the pathway back to the cell membrane. 5a-Cholesta-8-en-3-one teams up with a 3-keto-steroid reductase to create 5a-cholest-8-en-3b-ol. Then, stepping back into the endoplasmic reticulum membrane, 5a-cholest-8-en-3b-ol enlists the help of 3-beta-hydroxysteroid-delta(8),delta(7)-isomerase to produce lathosterol. Lathosterol and lathosterol oxidase work together to make 7-dehydrocholesterol . Finally, 7-dehydrocholesterol partners with 7-dehydrocholesterol reductase to create cholesterol, completing the final step in cholesterol biosynthesis."
What is the definition of Molting Hormone Biosynthesis?,"20-hydroxyecdysone is a steroid hormone that controls the ecdysis or molting of insects. It is formed from the modification of cholesterol by various p450 enzymes. Initially, cholesterol is modified by a cholesterol 7-desaturase, forming 7-dehydrocholesterol. In the endoplasmic reticulum, 7-dehydrocholesterol is modified by cytochrome p450 307a1 to form diketol. Diketol can interact with the cytochrome p450 306a1 enzyme, ecdysteroid 25-hydroxylase, forming 2,22-dideoxy-3-dehydroecdysone. In the mitochondria, 2,22-dideoxy-3-dehydroecdysone can be modified by cytochrome p450 302a1, also known as ecdysteroid 22-hydroxylase, which forms 3-dehydro-2-deoxyecdysone, which in turn can be modified by cytochrome p450 315a1, ecdysteroid 2-hydroxylase, to form 3-dehydroecdysone, one of the final products of this pathway.Diketol can also spontaneously form 3β,5β-ketodiol, which then interacts with the same enzymes as diketol. First, it is modified in the endoplasmic reticulum by cytochrome p450 306a1, ecdysteroid 25-hydroxylase to form 3β,5β-ketotriol. In the mitochondria, 3β,5β-ketotriol is then modified by cytochrome p450 302a1, ecdysteroid 22-hydroxylase, to form 2-deoxyecdysone, and then cytochrome 315a1, ecdysteroid 2-hydroxylase, to form ecdysone. From this point, ecdysone can interact with ecdysone oxidase to form 3-dehydroecdysone, the same product as in the first half of this pathway.In addition to this reaction, ecdysone can also interact with ecdysone 20-monooxygenase in the mitochondria to form 20-hydroxyecdysone (crustecdysone), which is the main molting hormone. Finally, 20-hydroxyecdysone can interact with cytochrome p450 18a1, 26-hydroxylase, in order to form 20,26-dihydroxyecdysone, the final product of this branch of the pathway."
What is the definition of Juvenile Hormone Synthesis?,"Juvenile hormones in insects are important for their growth before their adulthood, preventing metamorphosis if they undergo one. In Drosophila, only juvenile hormone III has been identified, while others exist in butterflies and moths.Synthesis of various forms of juvenile hormone III (JH III) start with farnesyl diphosphate interacting with an uncharacterized phosphatase protein, forming farnesol. Farnesol then interacts with NADP+ dependent farensol dehydrogenase, which removes a hydrogen ion from the hydroxyl group in order to form farnesal. Farnesal then enters the mitochondria and interacts with another uncharacterized aldehyde dehydrogenase which allows it to form farnesoic acid. Farnesoic acid can then interact with an unknown protein, similar to farnesoate epoxidase in Bombyx mori, in order to form juvenile hormone III acid (JH III acid). JH III acid can then interact with epoxide hydrolase in the membrane of the endoplasmic reticulum, forming the final product of this pathway, juvenile hormone III acid diol (JH III acid diol). It can also interact with juvenile hormone acid O-methyltransferase in order to form JH III, which is used in another set of reactions in this pathway.If farnesoic acid does not interact with the unknown protein, it may interact with juvenile hormone acid O-methyltransferase to form methyl farnesoate. Methyl farnesoate can then interact with a different unknown protein similar, to methyl farnesoate epoxidase in Diploptera punctata, in order to form JH III. In the mitochondria, JH III can interact with carboxylic ester hydrolase in order to form JH III acid, which then can form the final product, or form JH III again. Alternately, JH III can interact with epoxide hydrolase in the membrane of the endoplasmic reticulum, forming juvenile hormone III diol. This product then interacts with carboxylic ester hydrolase in the mitochondria, forming JH III acid diol, again, the end product of this pathway."
What is the definition of Drosopterin and Aurodrosopterin Biosynthesis?,"Drosopterin and aurodrosopterin are two of the 5 or more red pigment components involved in Drosophila eye color. Both are similar compounds, with aurodrosopterin lacking an amino group compared to drosopterin. Their synthesis starts with GTP, which is hydrolyzed by GTP cyclohydrolase to form 7,8-dihydroneopterin 3'-triphosphate. 7,8-dihydroneopterin 3'-triphosphate then has its triphosphate group cleaved by 6-pyruvoyl-tetrahydropterin synthase to form (6R)-6-pyruvoyl-5,6,7,8-tetrahydropterin (dyspropterin). A currently unknown reaction occurs to convert dyspropterin to 7,8-dihydropterin during which a side-chain is removed. This reaction could be spontaneous or enzyme catalyzed. From there, 7,8-dihydropterin is deaminated by 7,8-dihydropterin deaminase, forming 7,8-dihydrolymazine. Dyspropterin is also catalyzed by pyrimidodiazepine synthase to form 2-amino-6-acetyl-3,7,8,9-tetrahydro-3H-pyrimido[4,5-b][1,4]diazepin-4-one (pyrimidodiazepine). Pyrimidodiazepine can spontaneously react with either 7,8-dihydropterin to form drosopterin, or 7,8-dihydrolymazine to form aurodrosopterin, which is the final product of this pathway."
What is the definition of 11-cis-3-Hydroxyretinal Biosynthesis?,"(3S)-11-cis-3-hydroxyretinal is one of three chromophores, which then associate with rhodopsins. Specifically, this chromophore associates with the Rh1 rhodopsin, a blue/green sensitive visual pigment found in 6 of the 8 photoreceptor cells in Drosophila melanogaster.The production of this chromophore begins with zeaxanthin obtained from Drosophila’s dietary sources. This lipid is broken down into (3R)-11-cis-3-hydroxyretinal and (3R)-all-trans-3-hydroxyretinal by a carotenoid isomerooxygenase. The (3R)-cis-3-hydroxyretinal is then attached to a retinoid binding protein, and this complex goes on to be used in the visual cycle of the organism. However, (3R)-all-trans-3-hydroxyretinal must be further processed. It too binds to a retinoid binding protein that will remain unchanged through the rest of the reactions. First, this complex will have a hydrogen added by a photoreceptor dehydrogenase in order to form (3R)-all-trans-3-hydroxyretinol, and then a photoreceptor epimerase will invert its stereochemistry to form (3S)-all-trans-3-hydroxyretinol. From here, an unknown protein, an oxidoreductase that transposes C=C bonds, will form (3S)-11-cis-3-hydroxyretinol. Finally, another photoreceptor dehydrogenase removes a hydrogen from that complex, forming the final product, (3S)-11-cis-3-hydroxyretinal. This complex then joins (3R)-11-cis-3-hydroxyretinal in the visual cycle."
What is the definition of Ether Lipid Metabolism?,"Ether lipids are typically glycerophospholipids where the glycerol backbone has lipids attached by both an ether bond at the sn-1 position and an acyl group at the sn-2 position.This pathway starts with dihydroxyacetone phosphate acyl ester which comes from glycerophospholipid metabolism. In the peroxisome, it reacts with a long chain alcohol, catalyzed by alkyldihydroxyacetonephosphate synthase, and forms an alkyl-glycerone 3-phosphate. Following this, the enzyme acylglycerone-phosphate reductase adds a hydrogen ion to the alkyl-glycerone 3-phosphate, forming a 1-alkyl-sn-glycerol 3-phosphate. Following this, a long-chain fatty acyl group is added, taken from a long-chain fatty acyl-CoA, and catalyzed by an acyltransferase to form a 2-acyl-1-alkyl-sn-glycero-3-phosphate. The phosphate is then removed in a reaction catalyzed by putative phosphatide phosphatase, forming 2-acyl-1-alkyl-sn-glycerol. This can then have a phosphoethanolamine group added by an ethanolaminephosphotransferase in the endoplasmic reticulum membrane, to form 2-acyl-1-alkyl-sn-glycero-3-phosphoethanolamine. This compound then is acted upon by a plasmanylethanolamine desaturase to form O-1-alk-1-enyl-2-acyl-sn-glycero-3-phosphoethanolamine. O-1-alk-1-enyl-2-acyl-sn-glycero-3-phosphoethanolamine can then  react via phospholipase A2 to form a 1-alkenylglycerophosphoethanolamine, one of the end products of this pathway, or react via phospholipase D to form a 2-acyl-1-(1-alkenyl)-sn-glycero-3-phosphate, another end product of this pathway. It can also react reversibly using an ethanolaminephosphotransferase in the endoplasmic reticulum membrane to form  or be formed from a 1-alkenyl-2-acylglycerol.Alternatively, the 2-acyl-1-alkyl-sn-glycerol can react with CDP-choline, catalyzed by a diacylglycerol cholinephosphotransferase, in order to form a 1-radyl-2-acyl-sn-glycero-3-phosphocholine. This can then react using phospholipase A2 as the enzyme to form a 1-organyl-2-lyso-sn-glycero-3-phosphocholine which can then react using lysophosphatidylcholine acyltransferase in the endoplasmic reticulum membrane to reform 1-radyl-2-acyl-sn-glycero-3-phosphocholine. Alternatively, it can react with the lysophosphatidylcholine acyltransferase to form 2-O-acetyl-1-O-hexadecyl-sn-glycero-3-phosphocholine, also known as platelet-activating factor, the final end product of this pathway. This platelet-activating factor can then interact with platelet-activating factor acetylhydrolase to reform 1-organyl-2-lyso-sn-glycero-3-phosphocholine."
What is the definition of Fatty Acid Elongation?,"Fatty acids are formed from acetyl-CoA derived from carbohydrates. Saturated fatty acids are produced, up to 16 carbons in length, which may then be modified further. Additionally, these fatty acids may combine with differing types of bonds to form triacylglycerols or phospholipids.This pathway starts with acetyl-CoA and butyryl-CoA, a coenzyme A activated form of butyric acid, a 4-carbon fatty acid. The acetyl group is added to the chain by an acetyl-CoA acetyltransferase, which forms 3-oxohexanoyl-CoA. The 3-oxohexanoyl-CoA then reversibly has a hydrogen added by 3-hydroxyacyl-CoA dehydrogenase type-2 to  form (S)-hydroxyhexanoyl-CoA. A reaction then occurs that removes a water molecule from the compound using enoyl-CoA hydratase, forming trans-2-hexenoyl-CoA. Finally, trans-2-enoyl-CoA reductase removes a hydrogen, leaving the final product, hexanoyl-CoA.Following the formation of hexanoyl-CoA, acetyl-CoA acyltransferase then adds an acetyl group to it, forming 3-oxooctanoyl-CoA. The same reactions occur to transform this eventually into octanoyl-CoA. Octanoyl-CoA then has an acetyl group added to it, eventually leading to the production of decanoyl-CoA, lauroyl-CoA, tetradecanoyl-CoA and finally the 16 carbon hexadecanoyl-CoA.Finally, hexadecanoyl is transported out of the mitochondrion and into the lysosome, where palmitoyl-protein thioesterase 1 catalyzes its reversible reaction with a water molecule that removes the CoA group and forms palmitic acid. Palmitic acid is the final product of this pathway, and it is involved in the fatty acid degradation pathway."
What is the definition of Lipoic Acid Metabolism?,"Lipoic acid is a compound derived from octanoic acid that is used as a cofactor in at least five enzyme systems, and is present in at least small amounts in most foods.However, these sources are covalently bound to other molecules, and aren't usable. Due to this, supplements of lipoic acid are synthesized chemically rather than obtained through natural sources.This pathway takes place entirely in the mitochondria, and begins with octanoyl bound to an acyl-carrier protein (ACP) from fatty acid biosynthesis. It can interact with lipoyl synthase to form lipoyl-ACP, after which it interacts with putative lipoyl transease in order to form protein N6-(lipoyl)lysine. Octanoyl-ACP  can also interact with those enzymes in the opposite order, first the putative lipoyltransferase 2, forming protein N6-(octanoyl)lysine, and then lipoyl synthase to form protein N6-(lipoyl)lysine.At the same time, lipoic acid can interact with a lipoate protein ligase, consisting of a currently unknown protein, adding a lipoyl-carrier protein-L-lysine, also forming a protein N6-(lipoyl)lysine. Finally, lipoic acid can form lipoyl-AMP after a reaction catalyzed by the same lipoate protein ligase, which can then interact with lipoyltransferase 1 to form the protein N6-(lipoyl)lysine. This is the final and only product of this pathway."
What is the definition of Nicotinate and Nicotinamide Metabolism?,"Nicotinate/nicotinic acid/niacin is a form of vitamin B3 that is primarily obtained through whole and processed, as well as fortified foods. Another form of vitamin B3 is nicotinamide/niacinamide, which is also obtained in trace amounts from dietary sources. Nicotinamide is critically important in the structure of  NAD(H) and NADP(H), which are both used as coenzymes in oxidation-reduction reactions such as the citric acid cycle and the electron transport chain.Nicotinic acid from dietary sources can be converted to and from nicotinate beta-D-ribonucleotide by nicotinate phosphoribosyltransferase. This compound may then be converted to nicotinate D-ribonucleoside by 5'-nucleotidase after the addition of a water molecule. Nicotinate D-ribonucleoside can then be converted to and from nicotinic acid by a purine-nucleoside phosphorylase. Nicotinate beta-D-ribonucleotide can also be converted to and from nicotinic acid adenine dinucleotide by nicotinamide-nucleotide adenylyltransferase. Following that reaction, it can be further converted to nicotinamide adenine dinucleotide (NAD) by a probable glutamine-dependent NAD synthetase.If the starting compound is instead nicotinamide, it undergoes reactions using the same three enzymes as nicotinic acid. Firstly, purine nucleoside phosphorylase catalyzes its conversion to nicotinamide riboside, following which a 5'-nucleotidase converts it to nicotinamide ribotide. Finally, nicotinamide-nucleotide adenylyltransferase takes nicotinamide ribotide and forms NAD. Finally, within the nucleus of the cell, NAD kinase takes a phosphate from ATP and forms NADP from NAD. This is then used in many reactions in the body."
What is the definition of Arsenate Detoxification?,"Arsenate is a compound similar to phosphate, but containing an arsenic atom instead of the phosphorous. As such, it is treated similarly to a phosphate ion. However, if the arsenate replaces inorganic phosphates in glycolysis, it allows glycolysis to proceed, but does not generate ATP, uncoupling glycolysis. It can also bind to lipoic acid in the Krebs cycle, leading to a greater loss of ATP.Arsenate can enter into the cell via aquaporins 7 and 9, as well as facilitated glucose transporter members 1 and 4 of solute carrier family 2, and does so by diffusion.Once inside the cell, the arsenate can be converted to arsenite via the glutathione S-transferase omega-1 enzyme, or it can be converted to ribose-1-arsenate via the purine nucleoside phosphorylase. Ribose-1-arsenate then can spontaneously form arsenite through a reaction involving hydrogen and dihydrolipoate. After arsenite has been formed by either of these methods, arsenite methyltransferase catalyzes its formation into methylarsonate. From here, it forms methylarsonite via the glutathione S-transferase omega-1 enzyme again. The methylarsonite reacts with S-adenosylmethionine, catalyzed by arsenite methyltransferase, in order to become dimethylarsinate. Finally, the compound once again interacts with the glutathione S-transferase omega-1 enzyme to form dimethylarsinous acid, the final compound in this pathway."
What is the definition of Eumelanin Biosynthesis?,"Melanin is the term used for multiple pigments found in many organisms, and specifically our skin, hair and iris tissues. There are three types of melanin, eumelanin, pheomelanin and neuromelanin. Eumelanin is the most common, and can be brown or black. Melanin is produced by melanocytes, and is a polymer made of smaller components, so there are many types with different polymerization patterns and proportions of components.To begin, this pathway takes L-dopachrome from the L-dopa and L-dopachrome biosynthesis pathways and, in the melanosome, it can either spontaneously form 5,6-dihydroxyindole, or can form 5,6-dihydroxyindole-2-carboxylic acid using L-dopachrome tautomerase as the catalyst. Both 5,6-dihydroxyindole and 5,6-dihydroxyindole-2-carboxylic acid use tyrosinase as a catalyst to form indole-5,6-quinone and indole-5,6-quinone-2-carboxylate respectively. Finally, some combination of 5,6-hydroxyindole, indole-5,6-quinone, 5,6-dihydroxyindole-2-carboxylic acid and indole-5,6-quinone-2-carboxylate combine to form melanochrome, an intermediate in the formation of eumelanin, and finally forms eumelanin, the final product of this pathway."
What is the definition of Aldosterone from Steroidogenesis ?,"Aldosterone is a hormone produced in the zona glomerulosa of the adrenal cortex.  It's function is to act on the distal convoluted tubule and the collecting duct of the nephron to make them more permeable to sodium to allow for its reuptake (in addition to allowing potassium wasting).  As a result, water follows the sodium back into the body. The water retention contributes to an increased blood volume.  Angiotensin II from the circulation binds to receptors on the zona glomerulosa cell membrane, activating the G protein and triggering a signaling cascade.  The end result is the activation of the steroidogenic acute regulatory (StAR) protein that permits cholesterol uptake into the mitochondria.  From there, cholesterol undergoes a series of reactions in both the mitochondrion and the smooth endoplasmic reticulum (steroidogenesis) where it finally becomes aldosterone."
What is the definition of Pancreas Function - Delta Cell?,"Pancreatic delta cells produce somatostatin which functions to inhibit glucagon, insulin, and itself.  Somatostatin is stored in granules in the delta cell and is released in response to an increase in blood sugar, calcium, and blood amino acids during absorption of a meal. In the process of somatostatin secretion, glucose must first undergo glycolysis in the mitochondrion to increase ATP in the cell. The inside of the alpha cell then becomes electrically positive due to the closure of potassium channels that were inhibited by ATP.  From this closure, the potassium is no longer being shuttled out of the cell, thus depolarizing the cell due to the extra intracellular potassium.  The resulting action potential from the increased membrane potential causes the voltage gate calcium channels to open, creating an influx of calcium into the cell.  This triggers the exocytosis of somatostatin granules from the delta cell. "
What is the definition of 2-Amino-3-Carboxymuconate Semialdehyde Degradation?,"This pathway is part of a major route of the degradation of L-tryptophan. It begins with 2-amino-3-carboxymuconate-6-semialdehyde which is generated from L-tryptophan degradation. The 2-amino-3-carboxymuconate-6-semialdehyde first is acted upon by a decarboxylase, forming 2-aminomuconic acid semialdehyde, which is then dehydrogenated by 2-aminomuconic semialdehyde dehydrogenase to form 2-aminomuconic acid. An unknown protein forms a 2-aminomuconate deaminase which forms (3E)-2-oxohex-3-enedioate, and a second unknown protein forms a 2-aminomuconate reductase, which forms oxoadipic acid from (3E)-2-oxohex-3-enedioate. Finally, within the mitochondria, oxoadipic acid is dehydrogenated and a coenzyme A is attached by the organelle’s oxoglutarate dehydrogenase complex, forming glutaryl-CoA. Glutaryl-CoA can then be further degraded."
What is the definition of Ketone Body Metabolism?,"Ketone bodies are three water-soluble molecules (acetoacetate, beta-hydroxybutyrate, and the spontaneous breakdown product of acetoacetate, acetone) containing the ketone group that are produced by the liver from fatty acids. Ketone bodies are readily transported into tissues outside the liver and converted into acetyl-CoA, which then enters the citric acid cycle and is oxidized in the mitochondria for energy. 2 Acetyl-CoA is catalyzed by acetyl-CoA acetyltransferase homolog, mitochondrial to produce CoA and acetoacetyl-CoA. This is a bi-directional reaction occurring in the mitochondrion. Acetyl-CoA is also produced through the process of  glycolysis outside of the mitochondrion. 3-Hydroxy-3-methylglutaryl-CoA and CoA are catalyzed by hydroxymethylglutaryl-CoA synthase to produce acetoacetyl-CoA, H2O, and acetyl-CoA. This is also a bi-directional reaction outside the mitochondrion. Additionally, acetoacetyl-CoA is a product of pyruvate metabolism and is involved in the separate process of fatty acid degradation. 3-Hydroxy-3-methylglutaryl-CoA is catalyzed by a uncharacterized protein outside of the mitochondrion and will produce acetoacetic acid (acetoacetate) and acetyl-CoA. Another bi-directional reaction occurring in the mitochondrion is succinyl-CoA and acetoacetic acid (acetoacetate) catalyzed by probable succinyl-CoA:3-ketoacid coenzyme A transferase, mitochondrial and producing acetoacetyl-CoA, and succinic acid (succinate). Acetoacetic acid is also produced through butanoate metabolism outside of the mitochondrion. "
What is the definition of Citrate Cycle?,"The citric acid cycle is the final common oxidative pathway for carbohydrates, fats and amino acids. It is the most important metabolic pathway for the energy supply to the body. TCA is the most important central pathway connecting almost all the individual metabolic pathways. Oxalacetic acid and GTP are catalyzed by phosphoenolypyruvate carboxykinase to form GDP, CO2, and phosphoenolpyruvic acid. This is a single direction reaction occurring outside of the mitochondria. Phosphoenolpyruvic acid then becomes part of the glycolysis/ gluconeogenesis processes outside of the mitochondria which will then produce pyruvic acid that will be trans-located back into the mitochondria. Within the mitochondria, the single direction reaction of pyruvic acid, ATP, and hydrogen carbonate catalyzed by pyruvate carboxylase 1 produces phosphate, ADP, and oxalacetic acid. Pyruvic acid and lipoamide-E are catalyzed by probable pyruvate dehydrogenase E1 component subunit alpha and pyruvate dehydrogenase E1 component subunit beta, mitochondrial to form CO2 and S-acetyldihydrolipoamide-E in a single direction reaction in the mitochondria. S-Acetyldihydrolipoamide-E and CoA are catalyzed by dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex and (R)-lipoic acid to form dihydrolipoamide-E and acetyl-CoA. This is a bi-directional reaction occurring in the mitochondria. Acetyl-CoA is an input compound in the fatty acid biosynthesis and fatty acid elongation in mitochondria sub-pathways, as well as an output compound in the fatty acid metabolism and Val, Leu & Ile degradation sub-pathways. Dihydrolipoamide-E and NAD are catalyzed by dihydrolipoyl dehydrogenase to produce NADH, H+, and lipoamide-E through a bi-directional reaction in the mitochondria. Oxalacetic acid, H2O, and acetyl-CoA are catalyzed by probable ATP-citrate synthase and probable citrate synthase to form CoA and citric acid in a bi-directional reaction in the mitochondria. Oxalacetic acid is an input and output compound in the sub-pathways alanine, aspartate and glutamate metabolism, and glyoxylate and dicarboxylate metabolism within the mitochondria. Citric acid is catalyzed by probable cytoplasmic aconitate hydratase to form H2O and cis-aconitic acid, which are then catalyzed again by probable cytoplasmic aconitate hydratase to form isocitric acid. This is a bi-directional reaction in the mitochondria. Isocitric acid is involved in two bi-directional reactions in the mitochondria to form 2- oxoglutaric acid. The first reaction is between isocitric acid and NADP+ catalyzed by isocitrate dehydrogenase [NADP] to produce NADPH, H+, and oxalosuccinic acid. Oxalosuccinic acid is then catalyzed by isocitrate dehydrogenase [NADP] to form CO2 and 2-oxoglutaric acid. The other reaction is between isocitric acid and NAD catalyzed by probable isocitrate dehydrogenase [NAD] subunit alpha, probable isocitrate dehydrogenase [NAD] subunit beta, and magnesium to produce NADH, CO2, H+, and 2-oxoglutaric acid. Oxoglutaric acid is an input compound in the sub-pathway arginine biosynthesis, as well as an input and output compound in the sub-pathways D-Gin & D-Glu metabolism, ascorbate and aldarate metabolism, and alanine, aspartate and glutamate metabolism. In a single direction reaction, oxoglutaric acid and lipoamide-E are catalyzed by 2-oxoglutarate dehydrogenase to form CO2 and S-Succinyldihydrolipoamide-E. S-Succinyldihydrolipoamide-E and CoA are catalyzed by dihydrolipoamide S-Succinyltransferase to produce dihydrolipoamide-E and succinyl-CoA in a bi-directional reaction in the mitochondria. Dihydrolipoamide-E and NAD catalyzed by dihydrolipoyl dehydrogenase produce NADH, H+, and lipoamide-E in a bi-directional reaction. Succinyl-CoA, GDP, and phosphate are catalyzed by succinate--CoA ligase [ADP/GDP-forming] subunit alpha and succinate--CoA ligase [GDP-forming] subunit beta to form CoA, GTP, and succinic acid through a bi-directional reaction. Succinyl-CoA is also an output compound of the sub-pathway Val, Leu & Ile degradation. In another bi-directional reaction, succinic acid and a quinone are catalyzed by succinate dehydrogenase [ubiquinone] flavoprotein subunit and FAD to produce a hydroquinone and fumaric acid. Fumaric acid is an input and output compound in the sub-pathways arginine biosynthesis and tyrosine metabolism within the mitochondria. Fumaric acid and H2O are catalyzed by probable fumarate hydratase to produce L-Malic acid in a bi-directional reaction. L-malic acid and NAD are catalyzed by probable malate dehydrogenase to produce NADH, H+, and oxalacetic acid through a bi-directional reaction."
What is the definition of L-Homomethionine Biosynthesis?,"A non-protein amino acid and a derivative of methionine, homomethionine is synthesized through the process of chain elongation. In Arabidopsis thaliana and other members of the Cruciferae (Brassicaceae) family, it is synthesized as part of a multi-step pathway to generate glucosinolates. Glucosinolates are likely employed as a defense mechanism and are believed to be responsible for the pungent odour and taste associated with this plant family. The process starts in the cytosol of the plant cell with l-methionine as the primary substrate before moving into the chloroplast as 2-oxo-4-methylthiobutanoic acid. In the chloroplast, 3-isopropylmalate dehydratase plays a noteworthy role in catalyzing multiple reactions in the final synthesis of L-homomethionine. "
What is the definition of Sesquiterpenoid Biosynthesis?,"Sesquiterpenoids have 15 carbons and three isoprene units. They are derived from farnesyl diphosphate. They may contain rings or be acyclic, depending on the bonds formed by the loss of the diphosphate group. First, the terpenoid backbone is synthesized, producing farnesyl pyrophosphate. Two molecules of farnesyl pyrophosphate then join together to form presqualene diphosphate, catalyzed by squalene synthase 1. Then, the same enzyme removes the pyrophosphate group and replaces it with a hydrogen ion, forming squalene. Squalene then undergoes oxidation of one of its bonds via squlene monooxygenase 1, to form (S)-2,3-epoxysqualene. This may then proceed to the steroid biosynthesis pathway or may react with an isomerase or lyase to form a chair-chair-chair-boat triterpenoid. Similarly, squalene may interact with an isomerase or lyase to form a chair-chair-chair-chair triterpenoid.After the backbone is complete, farnesyl pyrophosphate can have its pyrophosphate removed by different enzymes, leading to different conformations of sesquiterpenoids. If it interacts with (Z)-gamma-bisabolene synthase, it forms gamma-bisabolene. If it interacts wtih (+)-alpha-barbatene synthase, it forms (+)-alpha-barbatene, if it interacts wtih beta-chamigrene synthase it forms (+)-beta-chamigrene, and finally if it interacts with thujopsene synthase it forms (+)-thujopsene."
What is the definition of Jasmonic Acid Biosynthesis?,"Jasmonic acid is an organic compound belonging to the family of jasmonates compounds found in many plants including jasmine. It functions as a phytohormone and is involved in many crucial physiological roles associated with plant growth and reproduction. Jasmonic acid is also commonly employed by plants as a defense mechanism. Jasmonic acid is synthesized from alpha-linoleic acid in a multi-step reaction in the chloroplast that yields dinor-12-oxo-phytodienoate (OPDA) before being transported onto the peroxisome where three enzymes -- acyl coenzyme A oxidase, OPC4-3-ketoacyl-CoA thiolase, and peroxisomal fatty acid beta-oxidation multifunctional protein A1M1 -- play important roles in the final synthesis alongside coenzyme A."
What is the definition of Triterpenoid Biosynthesis?,"Triterpenoids have 30 carbons and six isoprene units. They are derived from (S)-2,3-epoxysqualene. They may contain rings or be acyclic, depending on the bonds formed by the loss of the diphosphate group. First, the terpenoid backbone is synthesized, producing farnesyl pyrophosphate. Two molecules of farnesyl pyrophosphate then join together to form presqualene diphosphate, catalyzed by squalene synthase 1. Then, the same enzyme removes the pyrophosphate group and replaces it with a hydrogen ion, forming squalene. Squalene then undergoes oxidation of one of its bonds via squlene monooxygenase 1, to form (S)-2,3-epoxysqualene. This may then proceed to the steroid biosynthesis pathway or may react with an isomerase or lyase to form a chair-chair-chair-boat triterpenoid. Similarly, squalene may interact with an isomerase or lyase to form a chair-chair-chair-chair triterpenoid. After the backbone is complete, (S)-2,3-epoxysqualene can interact with many enzymes in order to form the triterpenoids. It can interact with camelliol C synthase to form camelliol C, thalianol synthase to form thalianol, baruol synthase to form baruol, tirucalladienol synthase to form tirucalla-7,24-dien-3-beta-ol, amyrun synthase LUP2 to form lupeol, alpha- and beta-amyrin synthases to form alpha- and beta-amyrin respectively. It can also interact with lupan-3beta,20-diol synthase to add a water molecule to form lupan-3beta,20-diol, alpha- and beta-seco-amyrin synthases to form alpha- and beta-seco-amyrin respectively, marneral synthase to form marneral, and finally arabidiol synthase to add a water molecule and form arabidiol."
What is the definition of MEP/DOXP Pathway?,"The DOXP/MEP pathway, also known as the non-mevalonate pathway, plays an essential role in creating the chemicals needed for many plants to function. This pathway, combined with the MEP/DOXP pathway give many plants their scents, such as cinnamon and ginger, and are responsible for the red colour in tomatoes. Terpenoids, also called isoprenoids, are a substantial yet varied class of organic chemicals that occur naturally. Plant terpenoids have aromatic qualities and are used for this and their role in traditional herbal remedies. The pathway begins with D-glyceraldehyde 3-phosphate, which is produced through glycolysis. Together with pyruvic acid and the enzyme 1-deoxy-D-xylulose 5-phosphate synthase 1, these are catalyzed into 1-deoxy-xylulose 5-phosphate. From there, 1-deoxy-xylulose 5-phosphate teams up with 1-deoxy-D-xylulose 5-phosphate reductoisomerase to create 2-c-methyl-D-erythritol 4-phosphate. Moving along in the chloroplast, after being produced through 2-c-methyl-D-erythritol 4-phosphate and the enzyme  2-c-methyl-D-erythritol 4-phosphate cytidyltransferase,4-cytidine 5'-diphospho)-2-C-methyl-D-erythritol is catalyzed by 4-diphosphocytidyl-2-c-methyl-D-erythritol kinase to create 2-phospho-4-(cytidine 5'-diphospho)-2-c-methyl-D-erythritol. After that, 2-c-methyl-D-erythritol 2,4-cyclodiphosphate synthase uses the newly produced 2-phospho-4-(cytidine 5'-diphospho)-2-c-methyl-D-erythritol to create 2-c-methyl-D-erythritol-2,4-cyclodiphosphate. This compound is then joined with 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase to become 1-hydroxy-2-methyl-2-butenyl 4-diphosphate. This compound gets busy soon after its inception,  branching off into two separate reactions: first reacting with 4-hydroxy-3-methylbut-2-enyl diphosphate reductase to create isopentenyl pyrophosphate, then reacting with the same enzyme to create dimethylallylpyrophosphate. Dimethylallylpyrophosphate is then looped into another reaction with isopentenyl-diphosphate delta-isomerase II, recreating isopentenyl pyrophosphate. It also reacts with geranylgeranyl pyrophosphate synthase 6, bringing the pathway into the mitochondrion to create geranyl pyrophosphate. This is later followed by a monoterpenoid biosynthesis pathway."
What is the definition of Mevalonate Pathway?,"The mevalonate pathway, also known as the isoprenoid pathway, plays an essential role in creating the chemicals needed for many plants to function. This pathway, combined with the MEP/DOXP pathway give many plants their scents, such as cinnamon and ginger, and are responsible for the red colour in tomatoes. The pathway begins with acetyl-CoA, having come from the glycolysis pathway. Acetyl-CoA immediately becomes acetoacetyl-CoA through the enzyme acetyl-CoA acetyltransferase 1/2. Combined, acetoacetyl-CoA and acetyl-CoA react with hydroxymethylglutaryl-CoA synthase to create 3-hydroxy-3methylglutaryl-CoA. From here, this compound is catalyzed by 3-hydroxy-3-methylglutaryl-coenzyme A reductase 1 and becomes (R)-mevalonate. Mevalonate is paired with mevalonate kinase to produce mevalonic acid-5P. In turn, mevalonic acid-5P reacts with phosphomevalonate kinase, and entering the peroxisome and becoming (R)-mevalonic acid-5-pyrophosphate. Remaining in the peroxisome, diphosphomevalonate decarboxylase MVD1 is used alongside (R)-mevalonic acid-5-pyrophosphate to create isopentenyl pyrophosphate, bringing the pathway into the chloroplast. Dimethylallylpyrophosphate is produced after isopentenyl pyrophosphate and isopentenyl diphosphate delta-isomerase II team up to catalyze it. Dimethylallylpyrophosphate then joins forces with isopentenyl again, this time adding geranylgeranyl pyrophosphate synthase 6 and moving into the mitochondria to produce geranyl-PP. This is followed by monoterpenoid biosynthesis. "
What is the definition of Terpenoid Backbone Biosynthesis?,"Terpenoids are a class of organic compounds made up of 5 carbon isoprene units. There are two pathways, melvalonate and MEP/DOXP, that synthesize the terpenoid backbone components. Both of these create isopentenyl pyrophosphate, which may then react using isopentenyl diphosphate isomerase in the chloroplast to form dimethylallylprophosphate. This molecule is also produced by the MEP/DOXP pathway.Isopentenyl pyrophosphate and dimethylallylprophosphate can react with geranylphosphate synthase in the mitochondrion to form geranyl-pyrophosphate, the main compound used in monoterpenoid biosynthesis. Geranyl-pyrophosphate may also react again with isopentenyl pyrophosphate using solanesyl diphosphate synthase 2 in the chloroplast to form solanesyl pyrophosphate, a potential end product of this pathway.Alternately, they can react with (2E,6E)-farnesyl diphosphate synthase, also in the mitochondrion, to form farnesyl phosphate. Farnesyl pyrophosphate may then be used as the main precursor in the sesquiterpenoid and triterpenoid biosynthesis pathways. It may also react with geranylgeranyl pyrophosphate 6 in the mitochondrion to form geranylgeranyl pyrophosphate. Geranylgeranyl pyrophosphate can react with isopentenyl pyrophosphate, catalyzed by solanesyl diphosphate syntahse 2, again in the chloroplast, to form solanesyl pyrophosphate. Aside this reaction, it can be converted by geranylgeranyl dehydrogenase in the chloroplast to form phytyl pyrophosphate, another end product of this pathway.Farnesyl pyrophosphate can additionally react using an undecaprenyl pyrophosphate synthetase family protein as a catalyst in order to form dehydrolichol pyrophosphate, or with the protein farnesyltransferase complex, which will add a protein-cysteine to the farnesyl pyrophosphate, which in turn loses its pyrophosphate group. The S-farnesyl protein then reacts with either CAAX prenyl protease 1 or 2 in the endoplasmic reticulum membrane to form protein C-terminal S-farnesyl-L-cysteine. This complex then reacts using protein-S-isoprenylcysteine O-methyltransferase B, still in the endoplasmic reticulum membrane, to form protein-C-terminal S-farnesyl-L-cysteine methyl ester. This reaction may be reversed by isoprenylcysteine alpha-carbonyl methylesterase, yet again in the endoplasmic reticulum membrane. Alternately, through an as of yet unknown reaction, the protein may be removed, as well as several other structure changes, leaving farnesylcysteine.In the lysosome, farnesylcysteine can be catalyzed by farnesylcysteine to remove the cysteine group, leaving behind farnesal. Then, a NAD-binding Rossman-fold superfamily protein can catalyze its transformation into farnesol. Finally, within the chloroplast, farnesol can be catalyzed by farnesol kinase to form farnesyl phosphate, the final product of this pathway."
What is the definition of Camalexin Biosynthesis?,"Camalexin is a compound produced by Arabadopsis thaliana, used in plant defense. Its accumulation is induced by contact with parasites, and it inhibits the growth of those parasites.Synthesis of camalexin starts with L-tryptophan, which reacts using tryptophan N-monooxygenases 1 and 2 to form N-hydroxy-L-tryptophan. This then reacts using the same enzyme to form N,N-dihydroxy-L-tryptophan, which spontaneously forms (E)-indol-3-ylacetaldoxime. (E)-indol-3-ylacetaldoxime reversibly reacts with a indoleacetaldoxime dehydratase enzyme to form (Z)-indol-3-ylacetaldoxime, its isomer. The isomer then loses a water molecule via indoleacetaldoxime dehydratase again, forming 3-indoleacetonitrile. Another reaction with indoleacetaldoxime dehydratase forms 2-hydroxy-2-(1H-indol-3-yl0acetonitrile, which then reacts one final time with the indoleacetaldoxime dehydratase enzyme to lose a water molecule and form dehydro(indole-3-yl)acetonitrile.At this point, a glutatione molecule is added using glutatione S-transferase F6 to form (glutation-S-yl)(1H-indol-3-yl)acetonitrile. A water molecule is added by gamma-glutamyl peptidases 1 and 3, as well as glutathione hydrolase 3, forming L-glutamic acid as a side product, as well as (L-cysteinylglycin-S-yl)(1H-indol-3-yl)acetonitrile. An unknown enzyme then catalyzes a reaction that adds a water molecule and removes a glycine, forming 2-(cystein-S-yl)-2-(1H-indol-3-yl)-acetonitrile. Then, in a reaction using bifunctional dihydrocamalexate synthase/camalexin synthase, an oxygen molecule is added, a hydrogen ion, hydrogen cyanide molecule and water molecule are removed, and (R)-dihydrocamalexate is formed. Finally, the same enzyme catalyzes the formation of camalexin, the final product of this pathway."
What is the definition of alpha-Linolenic Acid Metabolism?,"alpha-Linolenic acid is a poly-unsaturated fatty acid with an 18-carbon chain and three cis double bonds. Its primary role in Arabidopsis thaliana is in being a precursor of the phytohormone jasmonic acid. Being a precursor for jasmonic acid, it plays a role in gene responses to feeding from insects. It is also a precursor to other molecules involved in defense signalling such as cis-3-hexenyl acetate. alpha-Linolenic acid itself modulates gene transcription in response to hyperosmotic salinity, heat acclimation, and oxidative stress. alpha-Linolenic acid is released from the hydrolysis of a phosphatidylcholine membrane lipid. It then has a hydroperoxy group added by a dioxygenase in either the 2, 9, or 13 position to form 2(R)-HPOT, 9(S)-HPOT, or 13(S)-HPOT respectively. The oxidation of alpha-linolenic acid to 13(S)-HPOT is the first step in the jasmonic acid synthesis and leads to that separate pathway. 2(R)-HPOT is formed in an oil body and undergoes a spontaneous decarboxylation to form a heptadecatrienal.  9(S)-HPOT, or 13(S)-HPOT are both formed in a chloroplast and cleaved by probable inactive linolenate hydroperoxide lyase to form an aldehyde and an oxo-carboxylic acid. The hexenal from 13(S)-HPOT is reduced by alcohol dehydrogenase class-P to form a hexenol, which undergoes an esterification with acetyl-CoA to form 3-hexenyl acetate. "
What is the definition of Steroid Biosynthesis?,"The steroid biosynthesis pathway occurs in the endoplasmic reticulum leads to the production of various sterols. In Arabidopsis thaliana, the major products are cholesterol, brassicasterol, stigmasterol, campesterol, and their derivatives. These products serve various roles including signalling and structural support. Stigmasterol is the principal sterol in with campesterol being second most abundant.The pathway begins with farnesyl pyrophosphate produced in the terpenoid backbone biosynthesis pathway. Squalene synthase catalyzes the reaction of two molecules of farnesyl pyrophosphate to form presqualene diphosphate and then squalene. Squalene is reduced by squalene monoxygenase to form 2,3-epoxysqualene. 2,3-epoxysqualene can be used to form cycloartenol via cycloartenol synthase. This leads to the primary path of steroid biosynthesis in Arabidopsis thaliana. Cycloartenol undergoes a series of reactions to form 24-methylenelophenol. 24-methylenelophenol can be converted to 24-ethylidenelophenol by 24-methylenesterol C-methyltransferase. 24-methylenelophenol and 24-ethylidenelophenol undergo similar separate reactions to form two different sterols. 24-methylenelophenol and 24-ethylidenelophenol are reduced by methylsterol monooxygenase 2 to episterol and δ7-avenasterol respectively. These are oxidized by delta(7)-sterol-C5(6)-desaturase to 5-dehydroepisterol and 5-dehydroavenasterol. These then undergo a series of reductions to form 24-methylenecholesterol and avenasterol; 24-epi-campesterol and β-sitosterol; and finally brassicasterol and stigmasterol. 24-methylenecholesterol may also be reduced by delta(24)-sterol reductase to form campesterol.Alternatively, lanosterol synthase can use 2,3-epoxysqualene to form lanosterol. Lanosterol is reduced by sterol-14-demethylase to form 4,4-dimethylcholesta-8,14,24-trienoland then by delta(14)-sterol reductase to form 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol. 4,4-dimethyl-5a-cholesta-8,24-dien-3-b-ol then undergoes a series of reactions to for zymosterol. Zymosterol is converted into 5a-Cholest-8-en-3b-ol by delta(24)-sterol reductase, which is converted into lathosterol by 3-beta-hydroxysteroid-delta(8),delta(7)-isomerase, then into 7-dehydrocholesterol by 7-dehydrocholesterol reductase, then into cholesterol by 7-dehydrocholesterol reductase. "