DNA glycosylase (MutY in bacteria and hMYH in humans) is responsible for repairing misread A*oxoG residues to C*G by removing the inappropriately paired adenine base from the DNA backbone. It belongs to the Nudix hydrolase superfamily and is important for the repair of various genotoxic lesions. Enzymes belonging to this superfamily requires a divalent cation, such as Mg2+ or Mn2+ for their activity. They are also recognized by a highly conserved 23-residue nudix motif (GX5EX7REUXEEXGU, where U = I, L or V). However, DNA glycosylase does not seem to contain this signature motif. DNA glycosylase consists of 2 domains: the N-terminal domain contains the catalytic properties of the enzyme and the C-terminal domain affects substrate (oxoG) binding and enzymatic turnover. The C-terminal domain is highly similar to MutT, based on secondary structure and topology, despite low sequence identity. MutT sanitizes the nucleotide precursor pool by hydrolyzing oxo-dGTP to oxo-dGMO and inorganic pyrophosphate. The similarity strongly suggests that the two proteins share a common evolutionary origin.