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Identification of Antibacterial Immunity Proteins in Escherichia coli using MALDI-TOF-TOF-MS/MS and Top-Down Proteomic Analysis
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Published on: May 23, 2021

Genetic characterization of Vga ABC proteins conferring reduced susceptibility to pleuromutilins in Staphylococcus

Daniel R Gentry1, Lynn McCloskey, Michael N Gwynn

  • 1Department of Microbiology, ID-CEDD, GlaxoSmithKline, Collegeville, Pennsylvania 19426, USA. dan.r.gentry@gsk.com

Antimicrobial Agents and Chemotherapy
|October 8, 2008
PubMed

Insights

Six Staphylococcus aureus isolates showed reduced susceptibility to the antibiotic retapamulin. This resistance was linked to specific ABC proteins, VgaAv and VgaA, impacting pleuromutilin effectiveness.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Antimicrobial Resistance

Background:

  • Staphylococcus aureus is a significant human pathogen.
  • Pleuromutilins are a class of antibiotics used to treat bacterial infections.
  • Monitoring antibiotic susceptibility is crucial for effective treatment.

Purpose of the Study:

  • To investigate the prevalence of reduced susceptibility to retapamulin in recent clinical isolates of Staphylococcus aureus.
  • To identify the genetic mechanisms responsible for this reduced susceptibility.

Main Methods:

  • Minimum Inhibitory Concentration (MIC) testing was performed on 5,676 clinical isolates of Staphylococcus aureus.
  • Isolates exhibiting reduced susceptibility were further analyzed to identify resistance genes.

Main Results:

  • Six out of 5,676 S. aureus isolates displayed Minimum Inhibitory Concentrations (MICs) of >= 2 microg/ml for retapamulin.
  • The ATP-binding cassette (ABC) proteins, VgaAv and VgaA, were identified as the cause of reduced susceptibility to pleuromutilins in these isolates.

Conclusions:

  • The ABC proteins VgaAv and VgaA confer reduced susceptibility to pleuromutilins in Staphylococcus aureus.
  • These findings highlight the importance of monitoring for resistance mechanisms to ensure the continued efficacy of retapamulin.

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