L-methionine sulfone (2S)-2-amino-4-(methylsulfonyl)butanoic acid 163.0303192138671875 163.19000244140625 31.989828109741210938 32.0 A protein modification that dioxygenates an L-methionine residue to L-methionine sulfone. C 0 H 0 N 0 O 2 S 0 C 5 H 9 N 1 O 3 S 1 DeltaMass gives the formula C 5 H 9 N 3 O 1 S 1 with mass 163 Dioxidation L-methionine S,S-dioxide L-methionine sulfone M MOD:00256 MOD_RES Methionine sulfone MetO2 MethionylSulphone Oxidation of Methionine (to Sulphone) PSI-MOD S,S-dioxymethionine Unimod:425 dihydroxy natural suphonem uniprot.ptm:PTM-0175 sulfur oxygenated L-methionine sulfur dioxygenated residue