Altered induction of the adaptive response to alkylation damage in Escherichia coli recF mutants.
Escherichia coli recF mutants are hypermutable when treated with methyl methanesulfonate (G. C. Walker, Mol. Gen. Genet. 152:93-103, 1977). In this study, methylation hypermutability of recF mutant strains was examined, and it was found that recF+ is required for normal induction of the adaptive response to alkylation damage. Although this regulatory effect of recF mutations results in reduced levels of enzymes that specifically repair methyl lesions in DNA, it only partially explains the hypermutability. Further examination showed that methylation hypermutability of recF mutant strains required a functional umuDC operon, a component of the SOS response. These results lead to the hypothesis that methylation hypermutability results from the effects of recF mutations on the induction of both the SOS response and the adaptive response.
Volkert
M R
MR
Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester 01655.
D000478:Alkylation; D001426:Bacterial Proteins / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D007700:Kinetics; D008741:Methyl Methanesulfonate / Q000494:pharmacology*; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology*; D009154:Mutation; D009876:Operon; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D008769:Methylnitronitrosoguanidine; D008741:Methyl Methanesulfonate; D001616:beta-Galactosidase