A repair system for 8-oxo-7,8-dihydrodeoxyguanine

Biochemistry. 1992 Nov 17;31(45):10964-8. doi: 10.1021/bi00160a004.


Active oxygen species can damage DNA and may play a role in aging and carcinogenesis. We have tested MutY glycosylase for activity on undamaged mispairs as well as mispairs formed with the oxidatively damaged substrates, 8-oxo-7,8-dihydrodeoxyguanine (GO) or 8-oxo-7,8-dihydrodeoxyadenine (AO). MutY acts as a glycosylase on four of the heteroduplexes tested, A/G, A/GO, A/C, and A/AO, removing the undamaged adenine from each substrate. Genetic data suggest that the primary substrate for MutY glycosylase in vivo is the A/GO mispair. We present biochemical evidence demonstrating that MutY glycosylase is an important part of a repair system that includes the MutM and MutT proteins. The GO repair system is dedicated to the repair of the oxidatively damaged guanine and the mutations it can induce.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine / analogs & derivatives
  • Base Sequence
  • DNA Damage
  • DNA Glycosylases*
  • DNA Repair*
  • DNA-Formamidopyrimidine Glycosylase
  • Guanine / analogs & derivatives*
  • Guanine / metabolism
  • Molecular Sequence Data
  • N-Glycosyl Hydrolases / genetics
  • N-Glycosyl Hydrolases / metabolism
  • Nucleic Acid Heteroduplexes
  • Substrate Specificity


  • Nucleic Acid Heteroduplexes
  • Guanine
  • 8-oxo-7,8-dihydrodeoxyguanine
  • 8-Hydroxy-2'-Deoxyguanosine
  • DNA Glycosylases
  • N-Glycosyl Hydrolases
  • mutY adenine glycosylase
  • DNA-Formamidopyrimidine Glycosylase