Point mutation in the pribnow box, the molecular basis of beta-lactamase overproduction in Klebsiella oxytoca

Antimicrob Agents Chemother. 1995 Jun;39(6):1365-8. doi: 10.1128/AAC.39.6.1365.

Abstract

Klebsiella oxytoca mutants resistant to a variety of beta-lactams were obtained in vitro on aztreonam. Constitutive beta-lactamase production was much higher in the mutants than in the susceptible strains (75-fold). The only difference observed in these mutants compared with the susceptible strains were point mutations in the Pribnow box: a transversion (G-->T) in the first base for one mutant or a transition (G-->A) in the fifth base of the -10 consensus sequence for the other three mutants. The transcriptional output of the beta-lactamase gene (blaOXY) from the mutants was significantly higher than that of the blaOXY gene from the susceptible strains.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Base Sequence
  • Conserved Sequence*
  • DNA, Bacterial / analysis
  • Gene Expression Regulation, Bacterial
  • Klebsiella / drug effects
  • Klebsiella / genetics*
  • Klebsiella / metabolism
  • Microbial Sensitivity Tests
  • Molecular Sequence Data
  • Point Mutation*
  • Promoter Regions, Genetic
  • Transcriptional Activation
  • beta-Lactam Resistance
  • beta-Lactamases / biosynthesis
  • beta-Lactamases / genetics*
  • beta-Lactams

Substances

  • Anti-Bacterial Agents
  • DNA, Bacterial
  • beta-Lactams
  • beta-Lactamases

Associated data

  • GENBANK/Z30178
  • GENBANK/Z30179
  • GENBANK/Z30181
  • GENBANK/Z30182
  • GENBANK/Z30208