Abstract
DNA, which carries genetic information, is easily damaged by reactive oxygen species,UV radiation and chemical agents, and DNA integrity is maintained by various nucleic acid enzymes. We carried out X-ray crystallographic studies of two types of nucleic acid enzymes, oxidative nucleotide hydrolase MutT and translesion DNA polymerase η. In this review, I will describe the mechanism of high substrate specificity for oxidative nucleotides by E. coli MutT and the visualization of nucleotidyl transfer reaction by human DNA polymerase η.
