MutM, a protein that prevents G.C----T.A transversions, is formamidopyrimidine-DNA glycosylase.
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).
Michaels
M L
ML
Molecular Biology Institute, University of California, Los Angeles 90024.
Pham
L
L
Cruz
C
C
Miller
J H
JH
D000080242:8-Hydroxy-2'-Deoxyguanosine; D001435:Bacteriophages / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D004260:DNA Repair / Q000235:genetics* / Q000502:physiology; D004251:DNA Transposable Elements / Q000235:genetics*; D043382:DNA-Formamidopyrimidine Glycosylase; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000633:toxicity; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D029968:Escherichia coli Proteins; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional / Q000235:genetics; D009699:N-Glycosyl Hydrolases / Q000235:genetics*; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis
D004251:DNA Transposable Elements; D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; D000080242:8-Hydroxy-2'-Deoxyguanosine; D009699:N-Glycosyl Hydrolases; D043382:DNA-Formamidopyrimidine Glycosylase; C468610:DNA-formamidopyrimidine glycosylase, E coli; D003849:Deoxyguanosine