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Thiotaurine
Thiotaurine is a bioactive analog of taurine. It is used as a moisturizer and antioxidant in some cosmetic products. Preparation Thiotaurine is made by transsulfuration The transsulfuration pathway is a metabolic pathway involving the interconversion of cysteine and homocysteine through the intermediate cystathionine. Two transsulfurylation pathways are known: the ''forward'' and the ''reverse''. The ''forward ... of thiocysteine and hypotaurine. References Amino acids {{OrganicAcid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taurine
Taurine (), or 2-aminoethanesulfonic acid, is a naturally occurring amino sulfonic acid that is widely distributed in animal tissues. It is a major constituent of bile and can be found in the large intestine. It is named after Latin (cognate to Ancient Greek , ) meaning bull or ox, as it was first isolated from ox bile in 1827 by German scientists Friedrich Tiedemann and Leopold Gmelin. It was identified in human bile in 1846 by Edmund Ronalds. Although taurine is abundant in human organs, it is not an essential human dietary nutrient and is not included among nutrients with a recommended intake level. Among the diverse pathways by which natural taurine can be biosynthesized, its human pathways (primarily in the human liver) are from cysteine and/or methionine. Taurine is commonly sold as a dietary supplement, but there is no good clinical evidence that taurine supplements provide any benefit to human health. Taurine is used as a food additive for cats (who require ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transsulfuration Pathway
The transsulfuration pathway is a metabolic pathway involving the interconversion of cysteine and homocysteine through the intermediate cystathionine. Two transsulfurylation pathways are known: the ''forward'' and the ''reverse''. The ''forward pathway'' is present in several bacteria, such as ''Escherichia coli'' and ''Bacillus subtilis'', and involves the transfer of the thiol group from cysteine to homocysteine (methionine precursor with the S-methyl group), thanks to the γ-replacement of the acetyl or succinyl group of a homoserine with cysteine via its thiol group to form cystathionine (catalysed by cystathionine γ-synthase, which is encoded by ''metB'' in ''E. coli'' and ''metI'' in ''B. subtilis''). Cystathionine is then cleaved by means of the β-elimination of the homocysteine portion of the molecule leaving behind an unstable imino acid, which is attacked by water to form pyruvate and ammonia (catalysed by the metC-encoded cystathionine β-lyase). The production ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypotaurine
Hypotaurine is a sulfinic acid that is an intermediate in the biosynthesis of taurine. Like taurine, it also acts as an endogenous neurotransmitter via action on the glycine receptors. It is an osmolyte with antioxidant properties. Hypotaurine is derived from cysteine (and homocysteine). In mammals, the biosynthesis of hypotaurine from cysteine occurs in the pancreas. In the cysteine sulfinic acid pathway, cysteine is first oxidized to its sulfinic acid, catalyzed by the enzyme cysteine dioxygenase. Cysteine sulfinic acid, in turn, is decarboxylated by sulfinoalanine decarboxylase The enzyme sulfinoalanine decarboxylase () catalysis, catalyzes the chemical reaction :3-sulfino-L-alanine \rightleftharpoons hypotaurine + CO2 Hence, this enzyme has one substrate (biochemistry), substrate, 3-sulfino-L-alanine (also known as C ... to form hypotaurine. Hypotaurine is enzymatically oxidized to yield taurine by hypotaurine dehydrogenase. References Aminoethyl compound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
