Serratia marcescens rpr gene sensitizes Escherichia coli wild-type, xth, and nfo strains to methyl methanesulphonate.
It is reported here that the rpr DNA repair gene of Serratia marcescens does not complement an Escherichia coli xth nfo AP endonuclease mutation for resistance to methyl methanesulphonate (MMS). Rather, rpr sensitized Escherichia coli wild-type, xth, and nfo strains to MMS. Also, it was found that rpr could not complement a triple tag alkA recA mutation in E. coli, indicating that there are limits to rpr complementing capabilities. It was determined that rpr gene dosage was not a factor in recA complementation. MMS sensitization of an E. coli wild-type strain, however, was directly related to rpr copy number. These data indicate that Rpr does not have an associated AP endonuclease activity, and that it is incapable of substituting for Tag I, Tag II, and RecA in a tag alkA recA background.
Murphy
K E
KE
Department of Microbiology, Louisiana State University, Baton Rouge 70803.
Braymer
H D
HD
D045647:DNA Glycosylases; D004260:DNA Repair; D004269:DNA, Bacterial / Q000187:drug effects*; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D043223:Deoxyribonuclease IV (Phage T4-Induced); D004352:Drug Resistance, Microbial; D004706:Endodeoxyribonucleases / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D005784:Gene Amplification; D005816:Genetic Complementation Test; D008741:Methyl Methanesulfonate / Q000494:pharmacology*; D009154:Mutation; D009699:N-Glycosyl Hydrolases / Q000235:genetics; D012706:Serratia marcescens / Q000235:genetics*
D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D008741:Methyl Methanesulfonate; D004706:Endodeoxyribonucleases; D043223:Deoxyribonuclease IV (Phage T4-Induced); C468972:endonuclease IV, E coli; C021565:3-methyladenine-DNA glycosylase; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase