| Abstract: | Abstract— S-Methylcysteine, methionine and cystine were found to be photochemically deaminated at a much higher rate than methionine sulfoxide, homomethionine and other non-sulfur amino acids in the presence of flavin mononucleotide. These data strongly support the view that the initial oxidation of those sulfur-amino acids by the photoactivated flavin is a one-electron abstraction from the sulfur atom followed by an intramolecular electron transfer from the carboxyl anion of the amino acid to the sulfinium radical, resulting in the decarboxylation-deamination. |
