D942CF7018693CD56BAC30B86D1E93DB1CEAF3184D4F95099BC7BD51F09ECA398E627D590AD46B13560CFA27EF1AF008

FMN binds covalently to cysteine after exposure to blue light and this bond is spontaneously broken in the dark (By similarity).

Source:http://purl.uniprot.org/SHA-384/D942CF7018693CD56BAC30B86D1E93DB1CEAF3184D4F95099BC7BD51F09ECA398E627D590AD46B13560CFA27EF1AF008