MutM, a Protein That Prevents G.C----T.A Transversions, Is formamidopyrimidine-DNA Glycosylase

Nucleic Acids Res. 1991 Jul 11;19(13):3629-32. doi: 10.1093/nar/19.13.3629.


We have cloned chromosomal DNA bordering an insert that inactivates mutM. Sequencing of this clone has revealed that the insertion element is located between the promoter and structural gene for formamidopyrimidine-DNA glycosylase (Fapy-DNA glycosylase). An overproducing clone of Fapy-DNA glycosylase complements the original mutM strain that had been isolated after EMS mutagenesis. Thus, we conclude that MutM is actually Fapy-DNA glycosylase. mutM has previously been characterized as a mutator strain that leads specifically to G.C----T.A transversions. This in vivo characterization correlates well with the mutagenic potential of one of the lesions Fapy-DNA glycosylase removes, 8-oxo-7,8-dihydro-2'-deoxyguanine (8-OxodG).

Publication types

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

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine
  • Bacteriophages / genetics
  • Base Sequence
  • Cloning, Molecular
  • DNA Repair / genetics*
  • DNA Repair / physiology
  • DNA Transposable Elements / genetics*
  • DNA-Formamidopyrimidine Glycosylase
  • Deoxyguanosine / analogs & derivatives
  • Deoxyguanosine / toxicity
  • Escherichia coli / drug effects
  • Escherichia coli / genetics*
  • Escherichia coli Proteins*
  • Genetic Complementation Test
  • Molecular Sequence Data
  • Mutagenesis, Insertional / genetics
  • N-Glycosyl Hydrolases / genetics*
  • Plasmids / genetics
  • Promoter Regions, Genetic / genetics
  • Recombinant Proteins / biosynthesis


  • DNA Transposable Elements
  • Escherichia coli Proteins
  • Recombinant Proteins
  • 8-Hydroxy-2'-Deoxyguanosine
  • N-Glycosyl Hydrolases
  • DNA-Formamidopyrimidine Glycosylase
  • DNA-formamidopyrimidine glycosylase, E coli
  • Deoxyguanosine