May have a photoreceptor function. Binds DNA; represses transcription of at least 8 genes, including slr0364 and slr1866. Does not encode a DNA photolyase function. Its disruption does not affect circadian rhythm. Binds 1 FAD per subunit. Binds 1 5,10-methenyltetrahydrofolate (MTHF) per subunit. Belongs to the DNA photolyase class-1 family.