Redox-State-Dependent Structural Changes within a Prokaryotic 6-4 Photolyase.

ABSTRACT: Photolyases repair UV damage to DNA by using absorbed blue light. Within the photolyase/cryptochrome superfamily (PCSf), a major subgroup consists of prokaryotic (6-4) photolyases. These enzymes rely on flavin adenine dinucleotide (FAD) as a catalytic cofactor, besides an ancillary antenna chromophore, and a [4Fe-4S] cluster with yet unknown function. For the prokaryotic 6-4 photolyase of Caulobacter crescentus, we investigated structural changes associated with its different redox states by damage-free crystallography using X-ray free-electron lasers. EPR and optical spectroscopy confirmed redox-dependent structural transitions, including the formation of an oxidized [4Fe-4S]³⁺ cluster with the dynamic cleavage of a single iron-sulfur bond. Photoreduction to the catalyti

SUBMITTER: Wang PH 

PROVIDER: S-EPMC12082625 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature