REPAIR OF 8-OXOGUANINE IN DNA. THE MECHANISMS OF ENZYMATIC CATALYSIS

Data are summarised on the key enzymes involved in the repair of 8-oxoguanine, which is one of the most abundant DNA oxidative damage products possessing mutagenic activity. The literature data on the substrate specificity of prokaryotic and eukaryotic 8-oxoguanine DNA N-glycosylases, adenine DNA N-glycosylases and 8-oxoguanosine triphosphatases, their active site structures and structural functional features are presented. Special attention is given to the chemical aspects of the mechanisms of the catalytic action of these enzymes including stereochemistry of the catalytic processes.