Mutants suppressing novobiocin hypersensitivity of a mukB null mutation.
The mukB gene is essential for the partitioning of sister chromosomes in Escherichia coli. A mukB null mutant is hypersensitive to the DNA gyrase inhibitor novobiocin. In this work, we isolated mutants suppressing the novobiocin hypersensitivity of the mukB null mutation. All suppressor mutations are localized in or near the gyrB gene, and the four tested clones have an amino acid substitution in the DNA gyrase beta subunit. We found that in the mukB mutant, the process of sister chromosome segregation is strikingly hypersensitive to novobiocin; however, the effect of novobiocin on growth, which was measured by culture turbidity, is the same as that of the wild-type strain.
Adachi
Shun
S
Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Konoe, Yoshida, Sakyo, Kyoto 606-8501, Japan.
Hiraga
Sota
S
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone; D002876:Chromosomes, Bacterial; D027081:DNA Gyrase / Q000235:genetics / Q000378:metabolism; D024881:Drug Resistance, Bacterial; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000528:radiation effects; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009675:Novobiocin / Q000494:pharmacology*; D013489:Suppression, Genetic; D014965:X-Rays / Q000009:adverse effects
D001426:Bacterial Proteins; D002868:Chromosomal Proteins, Non-Histone; D004791:Enzyme Inhibitors; D029968:Escherichia coli Proteins; C067035:MukB protein, E coli; D009675:Novobiocin; D027081:DNA Gyrase