Macrolide antibiotic-mediated downregulation of MexAB-OprM efflux pump expression in Pseudomonas aeruginosa

Antimicrob Agents Chemother. 2008 Nov;52(11):4141-4. doi: 10.1128/AAC.00511-08. Epub 2008 Aug 1.

Abstract

Macrolide antibiotics modulate the quorum-sensing system of Pseudomonas aeruginosa. We tested the effect of macrolide antibiotics on the cell density-dependent expression of the MexAB-OprM efflux pump and found that 1.0 mug/ml (MIC/6.25) of azithromycin suppressed the expression of MexAB-OprM by about 70%, with the result that the cells became two- to fourfold more susceptible to antibiotics such as aztreonam, tetracycline, carbenicillin, chloramphenicol, and novobiocin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Azithromycin / pharmacology
  • Bacterial Outer Membrane Proteins / genetics
  • Bacterial Outer Membrane Proteins / metabolism*
  • Down-Regulation / drug effects
  • Humans
  • Macrolides / pharmacology*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism*
  • Microbial Sensitivity Tests
  • Pseudomonas Infections / drug therapy
  • Pseudomonas aeruginosa / drug effects*
  • Pseudomonas aeruginosa / genetics
  • Pseudomonas aeruginosa / metabolism*
  • Pseudomonas aeruginosa / pathogenicity
  • Quorum Sensing / drug effects

Substances

  • Anti-Bacterial Agents
  • Bacterial Outer Membrane Proteins
  • Macrolides
  • Membrane Transport Proteins
  • MexA protein, Pseudomonas aeruginosa
  • MexB protein, Pseudomonas aeruginosa
  • OprM protein, Pseudomonas aeruginosa
  • Azithromycin