S-phycoviolobilin-L-cysteine 586.27911376953125 586.67999267578125 689.288330078125 689.82000732421875 cryptoviolobilin cryptoviolin cryptobiliviolin C (4S)-3-[(1R)-1-(((2R)-2-amino-2-carboxy)ethylsulfanyl)ethyl]-8,12-bis(2-carboxyethyl)-18-ethyl-4,5-dihydro-2,7,13,17-tetramethyl-(21H,22H,24H)-biladiene-bc-1,19-dione natural A protein modification that effectively results from forming an adduct between a cysteine residue and the tetrapyrrole compound phycoviolobilin. Phycocyanobilin MOD:00263 S-phycoviolobilin-L-cysteine BINDING Phycoviolobilin chromophore (covalent; via 1 link) C 36 H 43 N 5 O 7 S 1 PSI-MOD PBV none PXB C 33 H 38 N 4 O 6 S-phycobiliviolin-L-cysteine phycocyanobilin PVB tetrapyrrole modified residue modified L-cysteine residue