Endonuclease_V, a DNA repair enzyme that initiates repair of nitrosative deaminated purine bases
Endonuclease_V (EndoV) is an enzyme that can initiate repair of all possible deaminated DNA bases. EndoV cleaves the DNA strand containing lesions at the second phosphodiester bond 3' to the lesion using Mg2+ as a cofactor. EndoV homologs are conserved throughout all domains of life from bacteria to humans. EndoV is encoded by the nfi gene and nfi null mutant mice have a phenotype prone to cancer. The ability of endonuclease V to recognize mismatches and abnormal replicative DNA structures suggests that the enzyme plays an important role in DNA metabolism. The details of downstream processing for the EndoV pathway remain unknown.
Comment:The active site includes a base lesion-recognition pocket, a strand-separating wedge and a catalytic pocket.
Structure:2W35, Thermotoga maritime, the strand-separating wedge of EndoV positioned to present deaminated bases to the hydrophobic lesion-specific pocket at the active site using Mg2+ as a cofactor