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ENZYME entry: EC

Accepted Name
(6-4)DNA photolyase
Alternative Name(s)
DNA photolyase
Reaction catalysed
(6-4) photoproduct (in DNA) <=> 2 pyrimidine residues (in DNA)
  • The overall repair reaction consists of two distinct steps, one of which is light-independent and the other one light-dependent.
  • In the initial light-independent step, a 6-iminium ion is thought to be generated via proton transfer induced by two histidines highly conserved among the (6-4) photolyases.
  • This intermediate spontaneously rearranges to form an oxetane intermediate by intramolecular nucleophilic attack.
  • In the subsequent light-driven reaction, one electron is believed to be transferred from the fully reduced FAD cofactor (FADH(-)) to the oxetane intermediate thus forming a neutral FADH radical and an anionic oxetane radical, which spontaneously fractures.
  • The excess electron is then back-transferred to the flavin radical restoring the fully reduced flavin cofactor and a pair of pyrimidine bases.
PRIAM enzyme-specific profiles4.1.99.13
KEGG Ligand Database for Enzyme Nomenclature4.1.99.13
IUBMB Enzyme Nomenclature4.1.99.13
MEDLINEFind literature relating to
Rhea expert-curated reactions4.1.99.13

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