CATH Classification
Level | CATH Code | Description |
---|---|---|
3 | Alpha Beta | |
3.40 | 3-Layer(aba) Sandwich | |
3.40.50 | Rossmann fold | |
3.40.50.620 | HUPs |
Domain Context
CATH Clusters
Superfamily | HUPs |
Functional Family |
Enzyme Information
4.1.99.13 |
(6-4)DNA photolyase.
based on mapping to UniProt A9CH39
(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.
|
UniProtKB Entries (1)
A9CH39 |
PHRB_AGRFC
Agrobacterium fabrum str. C58
(6-4) photolyase
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PDB Structure
PDB | 4DJA |
External Links | |
Method | X-RAY DIFFRACTION |
Organism | |
Primary Citation |
Crystal structure of a prokaryotic (6-4) photolyase with an Fe-S cluster and a 6,7-dimethyl-8-ribityllumazine antenna chromophore.
Proc.Natl.Acad.Sci.USA
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