L-cysteic acid (L-cysteine sulfonic acid) 150.993927001953125 151.1399993896484375 47.984745025634765625 48.0 artifact cysteine sulphonic acid cysteine oxidation to cysteic acid A protein modification that effectively trioxygenates an L-cysteine residue to L-cysteine sulfonic acid. none cysteic acid O 3 PSI-MOD Cya L-cysteine sulfonic acid Trioxidation From DeltaMass: Notes:Treatment of cysteine by strongly oxidising reagents such as performic acid results in the complete oxidation of the sulphur atom. Such treatment is often carried out prior to amino acid analysis as the resulting cysteic acid is then resistant to acid degradation during the hydrolysis procedure. 2-azanyl-3-sulfopropanoic acid C 3 H 5 N 1 O 4 S 1 CysO3H C (2R)-2-amino-3-sulfopropanoic acid Cysteic acid, oxidation of cysteine MOD_RES Cysteine sulfonic acid (-SO3H) 3-sulfoalanine 2-amino-2-carboxyethanesulfonic acid cysteicacidc MOD:00460 sulfur oxygenated L-cysteine