S-Methylcysteine
chemical compound
S-Methylcysteine is the amino acid with the nominal formula CH3SCH2CH(NH2)CO2H. It is the S-methylated derivative of cysteine. This amino acid occurs widely in plants, including many edible vegetables.
Natural occurrence
S-Methylcysteine is not genetically coded, but it arises by post-translational methylation of cysteine. One pathway involves methyl transfer from alkylated DNA by zinc-cysteinate-containing repair enzymes such as methylated-DNA-protein-cysteine methyltransferase.
S-Methylcysteine sulfoxide is an oxidized derivative of S-methylcysteine that is found in onions.
MetaCyc contains a list of biochemical reactions producing and consuming this substance.
Other chemical properties
Beyond its biological context, S-methylcysteine has been examined as a chelating agent.
The public source identifies “S-Methylcysteine” as chemical compound. This brief keeps that definition visible, then builds a research path around S-Methylcysteine, chemical and compound.
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This entry incorporates text from “S-Methylcysteine” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.