L-cysteic acid (L-cysteine sulfonic acid) (2R)-2-amino-3-sulfopropanoic acid 150.993927001953125 151.1399993896484375 2-amino-2-carboxyethanesulfonic acid 2-azanyl-3-sulfopropanoic acid 3-sulfoalanine 47.984745025634765625 48.0 A protein modification that effectively trioxygenates an L-cysteine residue to L-cysteine sulfonic acid. C C 0 H 0 N 0 O 3 S 0 C 3 H 5 N 1 O 4 S 1 Cya CysO3H Cysteic acid, oxidation of cysteine 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. L-cysteine sulfonic acid MOD:00460 MOD_RES Cysteine sulfonic acid (-SO3H) PSI-MOD Trioxidation Unimod:345 artifact cysteic acid cysteicacidc cysteine oxidation to cysteic acid cysteine sulphonic acid uniprot.ptm:PTM-0634 sulfur oxygenated L-cysteine