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Quantification of Plasmid-Mediated Antibiotic Resistance in an Experimental Evolution Approach
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Quantification of Plasmid-Mediated Antibiotic Resistance in an Experimental Evolution Approach

Published on: December 14, 2019

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Plasmid-mediated quinolone resistance

George A Jacoby1, Jacob Strahilevitz2, David C Hooper3

  • 1Lahey Hospital and Medical Center, Burlington, MA 01805.

Microbiology Spectrum
|January 14, 2015
PubMed

Insights

Three plasmid-mediated quinolone resistance (PMQR) mechanisms, including qnr genes, AAC(6')-Ib, and efflux pumps, are spreading globally. These mechanisms confer low-level resistance, aiding the selection of higher resistance and complicating treatment.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • Plasmid-mediated quinolone resistance (PMQR) has emerged as a significant concern in antimicrobial resistance.
  • Understanding the genetic basis and spread of PMQR is crucial for effective treatment strategies.

Purpose of the Study:

  • To elucidate the three primary mechanisms of plasmid-mediated quinolone resistance.
  • To investigate the genetic origins and dissemination of PMQR determinants.

Main Methods:

  • Identification and characterization of plasmid-mediated quinolone resistance genes.
  • Analysis of gene association with mobile genetic elements and integrons.
  • Detection of PMQR in clinical and environmental isolates worldwide.

Main Results:

  • Three PMQR mechanisms identified: qnr genes (pentapeptide repeat family), AAC(6 ')-Ib acetylation, and efflux pumps (QepAB, OqxAB).
  • qnr genes originate from aquatic bacteria, are linked to mobile elements, and often found in integrons.
  • PMQR is globally distributed in clinical and environmental settings, indicating widespread dissemination.

Conclusions:

  • PMQR mechanisms contribute to low-level quinolone resistance, facilitating the selection of high-level resistance.
  • The spread of PMQR complicates the treatment of bacterial infections.
  • Continued surveillance and research are necessary to combat the growing threat of PMQR.

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