4-amino-3-isothiazolidinone-L-serine -2.0156500339508056641 -2.0199999809265136719 188.0255584716796875 188.2100067138671875 C 6 H 8 N 2 O 3 S 1 A protein modification that effectively crosslinks an L-cysteine residue and an L-serine residue to form 4-amino-3-isothiazolidinone-L-serine. natural 2-(4-amino-3-oxo-isothiazolidin-2-yl)-3-hydroxy-propanoic acid MOD:00349 none C, S (2S)-2-[(4R)-4-amino-3-oxo-1,2-thiazolidin-2-yl]-3-hydroxypropanoic acid 4-amino-3-isothiazolidinone-L-serine serine-cysteine sulphenyl amide cross-link N,N-(L-cysteine-1,S-diyl)-L-serine H -2 Cross-link 2. serine-cysteine sulfenyl amide cross-link CROSSLNK N,N-(cysteine-1,S-diyl)serine (Cys-Ser) PSI-MOD isothiazolidinone ring crosslinked residues crosslinked L-cysteine residue crosslinked L-serine residue