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Quantification of Plasmid-Mediated Antibiotic Resistance in an Experimental Evolution Approach
12:32

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

Published on: December 14, 2019

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Plasmid-mediated quinolone resistance: Two decades on

José Manuel Rodríguez-Martínez1, Jesús Machuca2, María Eliecer Cano3

  • 1Departamento de Microbiología, Universidad de Sevilla, Sevilla, Spain; Spanish Network for the Research in Infectious Diseases (REIPI RD12/0015), Instituto de Salud Carlos III, Madrid, Spain.

Drug Resistance Updates : Reviews and Commentaries in Antimicrobial and Anticancer Chemotherapy
|December 4, 2016
PubMed

Insights

Plasmid-mediated quinolone resistance (PMQR) involves target protection, efflux pumps, and drug modification. These mechanisms spread globally, posing a threat to antibiotic treatment by enabling higher resistance levels.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • Plasmid-mediated quinolone resistance (PMQR) has been recognized for two decades.
  • PMQR encompasses three primary mechanisms: target protection (Qnr proteins), active efflux (QepA, OqxAB), and drug modification (AAC(6')-Ib-cr).
  • PMQR genes are frequently linked to mobile genetic elements and integrons, facilitating their dissemination.

Purpose of the Study:

  • To review the mechanisms and spread of plasmid-mediated quinolone resistance.
  • To highlight the clinical and environmental significance of PMQR.
  • To discuss the implications of PMQR for antimicrobial therapy.

Main Methods:

  • Literature review of studies on PMQR mechanisms.
  • Analysis of gene association with mobile elements and integrons.
  • Examination of global distribution in clinical and environmental isolates.

Main Results:

  • Qnr proteins, QepA/OqxAB efflux pumps, and AAC(6')-Ib-cr are the key PMQR mechanisms.
  • PMQR genes are commonly found on plasmids and within integrons.
  • PMQR is widespread globally in various microbial isolates.
  • Low-level resistance from PMQR can synergize with chromosomal resistance to achieve clinical significance.

Conclusions:

  • PMQR mechanisms contribute to the global spread of quinolone resistance.
  • The combination of PMQR with other resistance factors poses a significant threat to effective antimicrobial treatment.
  • Continued surveillance and understanding of PMQR are crucial for public health.
Keywords:
AAC(6′)-Ib-crOqxABPlasmidQepAQnrQuinoloneResistance

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