Reaction Process: Reactome:R-TGU-2514859
Inactivation, recovery and regulation of the phototransduction cascade related metabolites
find 7 related metabolites which is associated with chemical reaction(pathway) Inactivation, recovery and regulation of the phototransduction cascade
ATP + Q9IA36 ⟶ ADP + phospho-p-S334,338,343-at-retinyl-RHO
Adenosine triphosphate
Adenosine triphosphate, also known as atp or atriphos, is a member of the class of compounds known as purine ribonucleoside triphosphates. Purine ribonucleoside triphosphates are purine ribobucleotides with a triphosphate group linked to the ribose moiety. Adenosine triphosphate is slightly soluble (in water) and an extremely strong acidic compound (based on its pKa). Adenosine triphosphate can be found in a number of food items such as lichee, alpine sweetvetch, pecan nut, and black mulberry, which makes adenosine triphosphate a potential biomarker for the consumption of these food products. Adenosine triphosphate can be found primarily in blood, cellular cytoplasm, cerebrospinal fluid (CSF), and saliva, as well as throughout most human tissues. Adenosine triphosphate exists in all living species, ranging from bacteria to humans. In humans, adenosine triphosphate is involved in several metabolic pathways, some of which include phosphatidylethanolamine biosynthesis PE(16:0/18:4(6Z,9Z,12Z,15Z)), carteolol action pathway, phosphatidylethanolamine biosynthesis PE(20:3(5Z,8Z,11Z)/15:0), and carfentanil action pathway. Adenosine triphosphate is also involved in several metabolic disorders, some of which include lysosomal acid lipase deficiency (wolman disease), phosphoenolpyruvate carboxykinase deficiency 1 (PEPCK1), propionic acidemia, and the oncogenic action of d-2-hydroxyglutarate in hydroxygluaricaciduria. Moreover, adenosine triphosphate is found to be associated with rachialgia, neuroinfection, stroke, and subarachnoid hemorrhage. Adenosine triphosphate is a non-carcinogenic (not listed by IARC) potentially toxic compound. Adenosine triphosphate is a drug which is used for nutritional supplementation, also for treating dietary shortage or imbalanc. Adenosine triphosphate (ATP) is a complex organic chemical that participates in many processes. Found in all forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer. When consumed in metabolic processes, it converts to either the di- or monophosphates, respectively ADP and AMP. Other processes regenerate ATP such that the human body recycles its own body weight equivalent in ATP each day. It is also a precursor to DNA and RNA . ATP is able to store and transport chemical energy within cells. ATP also plays an important role in the synthesis of nucleic acids. ATP can be produced by various cellular processes, most typically in mitochondria by oxidative phosphorylation under the catalytic influence of ATP synthase. The total quantity of ATP in the human body is about 0.1 mole. The energy used by human cells requires the hydrolysis of 200 to 300 moles of ATP daily. This means that each ATP molecule is recycled 2000 to 3000 times during a single day. ATP cannot be stored, hence its consumption must closely follow its synthesis (DrugBank). Metabolism of organophosphates occurs principally by oxidation, by hydrolysis via esterases and by reaction with glutathione. Demethylation and glucuronidation may also occur. Oxidation of organophosphorus pesticides may result in moderately toxic products. In general, phosphorothioates are not directly toxic but require oxidative metabolism to the proximal toxin. The glutathione transferase reactions produce products that are, in most cases, of low toxicity. Paraoxonase (PON1) is a key enzyme in the metabolism of organophosphates. PON1 can inactivate some organophosphates through hydrolysis. PON1 hydrolyzes the active metabolites in several organophosphates insecticides as well as, nerve agents such as soman, sarin, and VX. The presence of PON1 polymorphisms causes there to be different enzyme levels and catalytic efficiency of this esterase, which in turn suggests that different individuals may be more susceptible to the toxic effect of organophosphate exposure (T3DB). ATP is an adenosine 5-phosphate in which the 5-phosphate is a triphosphate group. It is involved in the transportation of chemical energy during metabolic pathways. It has a role as a nutraceutical, a micronutrient, a fundamental metabolite and a cofactor. It is an adenosine 5-phosphate and a purine ribonucleoside 5-triphosphate. It is a conjugate acid of an ATP(3-). An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter. Adenosine triphosphate is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Adenosine-5-triphosphate is a natural product found in Chlamydomonas reinhardtii, Arabidopsis thaliana, and other organisms with data available. Adenosine Triphosphate is an adenine nucleotide comprised of three phosphate groups esterified to the sugar moiety, found in all living cells. Adenosine triphosphate is involved in energy production for metabolic processes and RNA synthesis. In addition, this substance acts as a neurotransmitter. In cancer studies, adenosine triphosphate is synthesized to examine its use to decrease weight loss and improve muscle strength. Adenosine triphosphate (ATP) is a nucleotide consisting of a purine base (adenine) attached to the first carbon atom of ribose (a pentose sugar). Three phosphate groups are esterified at the fifth carbon atom of the ribose. ATP is incorporated into nucleic acids by polymerases in the processes of DNA replication and transcription. ATP contributes to cellular energy charge and participates in overall energy balance, maintaining cellular homeostasis. ATP can act as an extracellular signaling molecule via interactions with specific purinergic receptors to mediate a wide variety of processes as diverse as neurotransmission, inflammation, apoptosis, and bone remodelling. Extracellular ATP and its metabolite adenosine have also been shown to exert a variety of effects on nearly every cell type in human skin, and ATP seems to play a direct role in triggering skin inflammatory, regenerative, and fibrotic responses to mechanical injury, an indirect role in melanocyte proliferation and apoptosis, and a complex role in Langerhans cell-directed adaptive immunity. During exercise, intracellular homeostasis depends on the matching of adenosine triphosphate (ATP) supply and ATP demand. Metabolites play a useful role in communicating the extent of ATP demand to the metabolic supply pathways. Effects as different as proliferation or differentiation, chemotaxis, release of cytokines or lysosomal constituents, and generation of reactive oxygen or nitrogen species are elicited upon stimulation of blood cells with extracellular ATP. The increased concentration of adenosine triphosphate (ATP) in erythrocytes from patients with chronic renal failure (CRF) has been observed in many studies but the mechanism leading to these abnormalities still is controversial. (A3367, A3368, A3369, A3370, A3371). Adenosine triphosphate is a metabolite found in or produced by Saccharomyces cerevisiae. An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter. Adenosine triphosphate (ATP) is a nucleotide consisting of a purine base (adenine) attached to the first carbon atom of ribose (a pentose sugar). Three phosphate groups are esterified at the fifth carbon atom of the ribose. ATP is incorporated into nucleic acids by polymerases in the processes of DNA replication and transcription. ATP contributes to cellular energy charge and participates in overall energy balance, maintaining cellular homeostasis. ATP can act as an extracellular signaling molecule via interactions with specific purinergic receptors to mediate a wide variety of processes as diverse as neurotransmission, inflammation, apoptosis, and bone remodelling. Extracellular ATP and its metabolite adenosine have also been shown to exert a variety of effects on nearly every cell type in human skin, and ATP seems to play a direct role in triggering skin inflammatory, regenerative, and fibrotic responses to mechanical injury, an indirect role in melanocyte proliferation and apoptosis, and a complex role in Langerhans cell-directed adaptive immunity. During exercise, intracellular homeostasis depends on the matching of adenosine triphosphate (ATP) supply and ATP demand. Metabolites play a useful role in communicating the extent of ATP demand to the metabolic supply pathways. Effects as different as proliferation or differentiation, chemotaxis, release of cytokines or lysosomal constituents, and generation of reactive oxygen or nitrogen species are elicited upon stimulation of blood cells with extracellular ATP. The increased concentration of adenosine triphosphate (ATP) in erythrocytes from patients with chronic renal failure (CRF) has been observed in many studies but the mechanism leading to these abnormalities still is controversial. (PMID: 15490415, 15129319, 14707763, 14696970, 11157473). 5′-ATP. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=56-65-5 (retrieved 2024-07-01) (CAS RN: 56-65-5). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).
Adenosine diphosphate
Adenosine diphosphate (ADP), also known as adenosine pyrophosphate (APP), is an important organic compound in metabolism and is essential to the flow of energy in living cells. ADP consists of three important structural components: a sugar backbone attached to adenine and two phosphate groups bonded to the 5 carbon atom of ribose. The diphosphate group of ADP is attached to the 5’ carbon of the sugar backbone, while the adenine attaches to the 1’ carbon. ADP belongs to the class of organic compounds known as purine ribonucleoside diphosphates. These are purine ribobucleotides with diphosphate group linked to the ribose moiety. It is an ester of pyrophosphoric acid with the nucleotide adenine. Adenosine diphosphate is a nucleotide. ADP exists in all living species, ranging from bacteria to humans. In humans, ADP is involved in d4-gdi signaling pathway. ADP is the product of ATP dephosphorylation by ATPases. ADP is converted back to ATP by ATP synthases. ADP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase adenine. Adenosine diphosphate, abbreviated ADP, is a nucleotide. It is an ester of pyrophosphoric acid with the nucleotide adenine. ADP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase adenine. 5′-ADP. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=58-64-0 (retrieved 2024-07-01) (CAS RN: 58-64-0). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Adenosine 5'-diphosphate (Adenosine diphosphate) is a nucleoside diphosphate. Adenosine 5'-diphosphate is the product of ATP dephosphorylation by ATPases. Adenosine 5'-diphosphate induces human platelet aggregation and inhibits stimulated adenylate cyclase by an action at P2T-purinoceptors. Adenosine 5'-diphosphate (Adenosine diphosphate) is a nucleoside diphosphate. Adenosine 5'-diphosphate is the product of ATP dephosphorylation by ATPases. Adenosine 5'-diphosphate induces human platelet aggregation and inhibits stimulated adenylate cyclase by an action at P2T-purinoceptors.
S-adenosylhomocysteine (SAH)
C14H20N6O5S (384.12158300000004)
S-Adenosyl-L-homocysteine (SAH) is formed by the demethylation of S-adenosyl-L-methionine. S-Adenosylhomocysteine (AdoHcy or SAH) is also the immediate precursor of all of the homocysteine produced in the body. The reaction is catalyzed by S-adenosylhomocysteine hydrolase and is reversible with the equilibrium favoring formation of SAH. In vivo, the reaction is driven in the direction of homocysteine formation by the action of the enzyme adenosine deaminase which converts the second product of the S-adenosylhomocysteine hydrolase reaction, adenosine, to inosine. Except for methyl transfer from betaine and from methylcobalamin in the methionine synthase reaction, SAH is the product of all methylation reactions that involve S-adenosylmethionine (SAM) as the methyl donor. Methylation is significant in epigenetic regulation of protein expression via DNA and histone methylation. The inhibition of these SAM-mediated processes by SAH is a proven mechanism for metabolic alteration. Because the conversion of SAH to homocysteine is reversible, with the equilibrium favoring the formation of SAH, increases in plasma homocysteine are accompanied by an elevation of SAH in most cases. Disturbances in the transmethylation pathway indicated by abnormal SAH, SAM, or their ratio have been reported in many neurodegenerative diseases, such as dementia, depression, and Parkinsons disease (PMID:18065573, 17892439). Therefore, when present in sufficiently high levels, S-adenosylhomocysteine can act as an immunotoxin and a metabotoxin. An immunotoxin disrupts, limits the function, or destroys immune cells. A metabotoxin is an endogenous metabolite that causes adverse health effects at chronically high levels. Chronically high levels of S-adenosylhomocysteine are associated with S-adenosylhomocysteine (SAH) hydrolase deficiency and adenosine deaminase deficiency. S-Adenosylhomocysteine forms when there are elevated levels of homocysteine and adenosine. S-Adenosyl-L-homocysteine is a potent inhibitor of S-adenosyl-L-methionine-dependent methylation reactions. It is toxic to immature lymphocytes and can lead to immunosuppression (PMID:221926). S-adenosylhomocysteine, also known as adohcy or sah, is a member of the class of compounds known as 5-deoxy-5-thionucleosides. 5-deoxy-5-thionucleosides are 5-deoxyribonucleosides in which the ribose is thio-substituted at the 5position by a S-alkyl group. S-adenosylhomocysteine is slightly soluble (in water) and a moderately acidic compound (based on its pKa). S-adenosylhomocysteine can be found in a number of food items such as rapini, european plum, rambutan, and pepper (c. pubescens), which makes S-adenosylhomocysteine a potential biomarker for the consumption of these food products. S-adenosylhomocysteine can be found primarily in blood, cerebrospinal fluid (CSF), feces, and urine, as well as throughout most human tissues. S-adenosylhomocysteine exists in all living species, ranging from bacteria to humans. In humans, S-adenosylhomocysteine is involved in several metabolic pathways, some of which include phosphatidylcholine biosynthesis PC(14:0/18:3(9Z,12Z,15Z)), phosphatidylcholine biosynthesis PC(22:4(7Z,10Z,13Z,16Z)/22:0), phosphatidylcholine biosynthesis PC(20:3(5Z,8Z,11Z)/22:2(13Z,16Z)), and phosphatidylcholine biosynthesis PC(18:3(6Z,9Z,12Z)/22:5(7Z,10Z,13Z,16Z,19Z)). S-adenosylhomocysteine is also involved in several metabolic disorders, some of which include 3-phosphoglycerate dehydrogenase deficiency, hawkinsinuria, non ketotic hyperglycinemia, and tyrosine hydroxylase deficiency. Moreover, S-adenosylhomocysteine is found to be associated with neurodegenerative disease and parkinsons disease. S-adenosylhomocysteine is a non-carcinogenic (not listed by IARC) potentially toxic compound. S-Adenosyl-L-homocysteine (SAH) is an amino acid derivative used in several metabolic pathways in most organisms. It is an intermediate in the synthesis of cysteine and adenosine . [Spectral] S-Adenosyl-L-homocysteine (exact mass = 384.12159) and Adenosine (exact mass = 267.09675) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. [Spectral] S-Adenosyl-L-homocysteine (exact mass = 384.12159) and Cytidine (exact mass = 243.08552) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Acquisition and generation of the data is financially supported in part by CREST/JST. COVID info from PDB, Protein Data Bank, WikiPathways Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS SAH (S-Adenosylhomocysteine) is an amino acid derivative and a modulartor in several metabolic pathways. It is an intermediate in the synthesis of cysteine and adenosine[1]. SAH is an inhibitor for METTL3-METTL14 heterodimer complex (METTL3-14) with an IC50 of 0.9 μM[2]. SAH (S-Adenosylhomocysteine) is an amino acid derivative and a modulartor in several metabolic pathways. It is an intermediate in the synthesis of cysteine and adenosine[1]. SAH is an inhibitor for METTL3-METTL14 heterodimer complex (METTL3-14) with an IC50 of 0.9 μM[2].
Retinal
A carotenoid constituent of visual pigments. It is the oxidized form of retinol which functions as the active component of the visual cycle. It is bound to the protein opsin forming the complex rhodopsin. When stimulated by visible light, the retinal component of the rhodopsin complex undergoes isomerization at the 11-position of the double bond to the cis-form; this is reversed in "dark" reactions to return to the native trans-configuration. [HMDB]. Retinal is found in many foods, some of which are flaxseed, pepper (c. baccatum), climbing bean, and other soy product. Retinal is a carotenoid constituent of visual pigments. It is the oxidized form of retinol which functions as the active component of the visual cycle. It is bound to the protein opsin forming the complex rhodopsin. When stimulated by visible light, the retinal component of the rhodopsin complex undergoes isomerization at the 11-position of the double bond to the cis-form; this is reversed in "dark" reactions to return to the native trans-configuration. D020011 - Protective Agents > D000975 - Antioxidants > D002338 - Carotenoids CONFIDENCE standard compound; INTERNAL_ID 142
Cyclic GMP
Cyclic-gmp, also known as cgmp or guanosine 3,5-cyclic monophosphate, is a member of the class of compounds known as 3,5-cyclic purine nucleotides. 3,5-cyclic purine nucleotides are purine nucleotides in which the oxygen atoms linked to the C3 and C5 carbon atoms of the ribose moiety are both bonded the same phosphorus atom of the phosphate group. Cyclic-gmp is slightly soluble (in water) and a moderately acidic compound (based on its pKa). Cyclic-gmp can be found in a number of food items such as common sage, jews ear, java plum, and pepper (c. chinense), which makes cyclic-gmp a potential biomarker for the consumption of these food products. Cyclic-gmp can be found primarily in blood and cerebrospinal fluid (CSF), as well as throughout most human tissues. Cyclic-gmp exists in all living species, ranging from bacteria to humans. Moreover, cyclic-gmp is found to be associated with headache. Guanosine cyclic 3,5-(hydrogen phosphate). A guanine nucleotide containing one phosphate group which is esterified to the sugar moiety in both the 3- and 5-positions. It is a cellular regulatory agent and has been described as a second messenger. Its levels increase in response to a variety of hormones, including acetylcholine, insulin, and oxytocin and it has been found to activate specific protein kinases. (From Merck Index, 11th ed). Acquisition and generation of the data is financially supported in part by CREST/JST. COVID info from COVID-19 Disease Map Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS
Water
Water is a chemical substance that is essential to all known forms of life. It appears colorless to the naked eye in small quantities, though it is actually slightly blue in color. It covers 71\\% of Earths surface. Current estimates suggest that there are 1.4 billion cubic kilometers (330 million m3) of it available on Earth, and it exists in many forms. It appears mostly in the oceans (saltwater) and polar ice caps, but it is also present as clouds, rain water, rivers, freshwater aquifers, lakes, and sea ice. Water in these bodies perpetually moves through a cycle of evaporation, precipitation, and runoff to the sea. Clean water is essential to human life. In many parts of the world, it is in short supply. From a biological standpoint, water has many distinct properties that are critical for the proliferation of life that set it apart from other substances. It carries out this role by allowing organic compounds to react in ways that ultimately allow replication. All known forms of life depend on water. Water is vital both as a solvent in which many of the bodys solutes dissolve and as an essential part of many metabolic processes within the body. Metabolism is the sum total of anabolism and catabolism. In anabolism, water is removed from molecules (through energy requiring enzymatic chemical reactions) in order to grow larger molecules (e.g. starches, triglycerides and proteins for storage of fuels and information). In catabolism, water is used to break bonds in order to generate smaller molecules (e.g. glucose, fatty acids and amino acids to be used for fuels for energy use or other purposes). Water is thus essential and central to these metabolic processes. Water is also central to photosynthesis and respiration. Photosynthetic cells use the suns energy to split off waters hydrogen from oxygen. Hydrogen is combined with CO2 (absorbed from air or water) to form glucose and release oxygen. All living cells use such fuels and oxidize the hydrogen and carbon to capture the suns energy and reform water and CO2 in the process (cellular respiration). Water is also central to acid-base neutrality and enzyme function. An acid, a hydrogen ion (H+, that is, a proton) donor, can be neutralized by a base, a proton acceptor such as hydroxide ion (OH-) to form water. Water is considered to be neutral, with a pH (the negative log of the hydrogen ion concentration) of 7. Acids have pH values less than 7 while bases have values greater than 7. Stomach acid (HCl) is useful to digestion. However, its corrosive effect on the esophagus during reflux can temporarily be neutralized by ingestion of a base such as aluminum hydroxide to produce the neutral molecules water and the salt aluminum chloride. Human biochemistry that involves enzymes usually performs optimally around a biologically neutral pH of 7.4. (Wikipedia). Water, also known as purified water or dihydrogen oxide, is a member of the class of compounds known as homogeneous other non-metal compounds. Homogeneous other non-metal compounds are inorganic non-metallic compounds in which the largest atom belongs to the class of other nonmetals. Water can be found in a number of food items such as caraway, oxheart cabbage, alaska wild rhubarb, and japanese walnut, which makes water a potential biomarker for the consumption of these food products. Water can be found primarily in most biofluids, including ascites Fluid, blood, cerebrospinal fluid (CSF), and lymph, as well as throughout all human tissues. Water exists in all living species, ranging from bacteria to humans. In humans, water is involved in several metabolic pathways, some of which include cardiolipin biosynthesis CL(20:4(5Z,8Z,11Z,14Z)/18:0/20:4(5Z,8Z,11Z,14Z)/18:2(9Z,12Z)), cardiolipin biosynthesis cl(i-13:0/i-15:0/i-20:0/i-24:0), cardiolipin biosynthesis CL(18:0/18:0/20:4(5Z,8Z,11Z,14Z)/22:5(7Z,10Z,13Z,16Z,19Z)), and cardiolipin biosynthesis cl(a-13:0/i-18:0/i-13:0/i-19:0). Water is also involved in several metabolic disorders, some of which include de novo triacylglycerol biosynthesis tg(i-21:0/i-13:0/21:0), de novo triacylglycerol biosynthesis tg(22:0/20:0/i-20:0), de novo triacylglycerol biosynthesis tg(a-21:0/i-20:0/i-14:0), and de novo triacylglycerol biosynthesis tg(i-21:0/a-17:0/i-12:0). Water is a drug which is used for diluting or dissolving drugs for intravenous, intramuscular or subcutaneous injection, according to instructions of the manufacturer of the drug to be administered [fda label]. Water plays an important role in the world economy. Approximately 70\\% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a major source of food for many parts of the world. Much of long-distance trade of commodities (such as oil and natural gas) and manufactured products is transported by boats through seas, rivers, lakes, and canals. Large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a wide variety of chemical substances; as such it is widely used in industrial processes, and in cooking and washing. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, and diving .
S-Adenosylmethionine
S-adenosylmethionine, also known as sam or adomet, is a member of the class of compounds known as 5-deoxy-5-thionucleosides. 5-deoxy-5-thionucleosides are 5-deoxyribonucleosides in which the ribose is thio-substituted at the 5position by a S-alkyl group. S-adenosylmethionine is slightly soluble (in water) and a moderately acidic compound (based on its pKa). S-adenosylmethionine can be found in a number of food items such as common grape, half-highbush blueberry, jerusalem artichoke, and thistle, which makes S-adenosylmethionine a potential biomarker for the consumption of these food products. S-adenosylmethionine can be found primarily in blood, cerebrospinal fluid (CSF), feces, and urine, as well as throughout most human tissues. S-adenosylmethionine exists in all eukaryotes, ranging from yeast to humans. In humans, S-adenosylmethionine is involved in several metabolic pathways, some of which include phosphatidylcholine biosynthesis PC(22:1(13Z)/22:6(4Z,7Z,10Z,13Z,16Z,19Z)), phosphatidylcholine biosynthesis PC(22:0/18:3(9Z,12Z,15Z)), phosphatidylcholine biosynthesis PC(24:0/24:0), and phosphatidylcholine biosynthesis PC(20:5(5Z,8Z,11Z,14Z,17Z)/20:0). S-adenosylmethionine is also involved in several metabolic disorders, some of which include methylenetetrahydrofolate reductase deficiency (MTHFRD), 3-phosphoglycerate dehydrogenase deficiency, monoamine oxidase-a deficiency (MAO-A), and aromatic l-aminoacid decarboxylase deficiency. Moreover, S-adenosylmethionine is found to be associated with diabetes mellitus type 2 and neurodegenerative disease. S-adenosylmethionine is a non-carcinogenic (not listed by IARC) potentially toxic compound. S-Adenosyl methionine is a common cosubstrate involved in methyl group transfers, transsulfuration, and aminopropylation. Although these anabolic reactions occur throughout the body, most SAM-e is produced and consumed in the liver. More than 40 methyl transfers from SAM-e are known, to various substrates such as nucleic acids, proteins, lipids and secondary metabolites. It is made from adenosine triphosphate (ATP) and methionine by methionine adenosyltransferase (EC 2.5.1.6). SAM was first discovered by Giulio Cantoni in 1952 . Significant first-pass metabolism in the liver. Approximately 50\\\% of S-Adenosylmethionine (SAMe) is metabolized in the liver. SAMe is metabolized to S-adenosylhomocysteine, which is then metabolized to homocysteine. Homocysteine can either be metabolized to cystathionine and then cysteine or to methionine. The cofactor in the metabolism of homocysteine to cysteine is vitamin B6. Cofactors for the metabolism of homocysteine to methionine are folic acid, vitamin B12 and betaine (T3DB). S-Adenosylmethionine (CAS: 29908-03-0), also known as SAM or AdoMet, is a physiologic methyl radical donor involved in enzymatic transmethylation reactions and present in all living organisms. It possesses anti-inflammatory activity and has been used in the treatment of chronic liver disease (From Merck, 11th ed). S-Adenosylmethionine is a natural substance present in the cells of the body. It plays a crucial biochemical role by donating a one-carbon methyl group in a process called transmethylation. S-Adenosylmethionine, formed from the reaction of L-methionine and adenosine triphosphate catalyzed by the enzyme S-adenosylmethionine synthetase, is the methyl-group donor in the biosynthesis of both DNA and RNA nucleic acids, phospholipids, proteins, epinephrine, melatonin, creatine, and other molecules.