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.[1]
Biosynthesis
The amino acid is not genetically coded, but it arises by
post-translationalmethylation of cysteine. One pathway involves
methyl transfer from alkylated DNA by zinc-cysteinate-containing repair enzymes.[2][3]
Beyond its biological context, it has been examined as a
chelating agent.[4]
References
^Maw, George A. (1982). "Biochemistry of S-Methyl-L-Cysteine and its Principal Derivatives". Sulfur Reports. 2: 1–26.
doi:
10.1080/01961778208082422.
^He, Haiyang; Lipowska, Malgorzata; Xu, Xiaolong; Taylor, Andrew T.; Carlone, Maria; Marzilli, Luigi G. (2005). "Re(CO)3 Complexes Synthesized via an Improved Preparation of Aqueousfac-[Re(CO)3(H2O)3]+as an Aid in Assessing 99mTc Imaging Agents. Structural Characterization and Solution Behavior of Complexes with Thioether-Bearing Amino Acids as Tridentate Ligands". Inorganic Chemistry. 44 (15): 5437–5446.
doi:
10.1021/ic0501869.
PMID16022542.