2-(4-guanidinobutanoyl)-5-hydroxyimidazole-4-carbothionic acid -6.0469498634338378906 -6.0500001907348632812 254.0711669921875 254.2899932861328125 (4Z)-2-(4-guanidinobutanoyl)-5-oxo-4-(sulfanylmethylidene)-4,5-dihydro-1H-imidazole 2-(4-guanidinobutanoyl)-5-hydroxy-1H-imidazole-4-carbothioic O-acid natural 2-(4-guanidinobutanoyl)-5-hydroxy-4-thioformyl-1H-imidazole [tautomer] N-term MOD:01877 PSI-MOD C 9 H 12 N 5 O 2 S 1 H -6 2-(4-guanidinobutanoyl)-5-hydroxyimidazole-4-carbothionic acid Cross-link 2. CROSSLNK 2-(4-guanidinobutanoyl)-5-hydroxyimidazole-4-carbothionic acid (Arg-Cys) C, R A protein modification that effectively converts an L-cysteine residue and an L-arginine residue to 2-(4-guanidinobutanoyl)-5-hydroxyimidazole-4-carbothionic acid. 5-imidazolinone ring crosslinked residues (Cys) crosslinked L-arginine residue crosslinked L-cysteine residue