Overexpression of SmeDEF Efflux Pump Decreases Aminoglycoside Resistance in Stenotrophomonas maltophilia

Antimicrob Agents Chemother. 2017 Apr 24;61(5):e02685-16. doi: 10.1128/AAC.02685-16. Print 2017 May.

Abstract

The SmeDEF pump of Stenotrophomonas maltophilia is negatively regulated by SmeT. In this study, strains KJΔT (smeT deletion mutant) and KJT-Dm (mutant with a defective SmeT-binding site) showed increased resistance to chloramphenicol/nalidixic acid/macrolides and susceptibility to aminoglycoside. Overexpression of the SmeDEF pump, in either KJΔT or KJT-Dm, downregulated smeYZ expression, which is responsible for the reduced aminoglycoside resistance. Furthermore, the SmeRySy two-component regulatory system was downregulated in response to SmeDEF overexpression, which supports its involvement in the regulatory circuit.

Keywords: antibiotic resistance; bacteria; efflux pump; two-component regulatory system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amikacin / pharmacology
  • Aminoglycosides / pharmacology*
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / biosynthesis*
  • Bacterial Proteins / genetics
  • Chloramphenicol / pharmacology
  • Ciprofloxacin / pharmacology
  • Drug Resistance, Multiple, Bacterial / genetics
  • Erythromycin / pharmacology
  • Gentamicins / pharmacology
  • Kanamycin / pharmacology
  • Membrane Transport Proteins / biosynthesis*
  • Membrane Transport Proteins / genetics
  • Stenotrophomonas maltophilia / drug effects*
  • Stenotrophomonas maltophilia / genetics*

Substances

  • Aminoglycosides
  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Gentamicins
  • Membrane Transport Proteins
  • SmeD protein, Stenotrophomonas maltophilia
  • SmeE protein, Stenotrophomonas maltophilia
  • SmeF protein, Stenotrophomonas maltophilia
  • Kanamycin
  • Ciprofloxacin
  • Erythromycin
  • Chloramphenicol
  • Amikacin