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Molecular mechanisms of resistance in Pseudomonas aeruginosa to fluoroquinolones

A Speciale1, R Musumeci, G Blandino

  • 1Department of Microbiological and Ginecological Sciences, University of Catania, Via Androne 81, 95124, Catania, Italy.

International Journal of Antimicrobial Agents
|March 18, 2000
PubMed

Insights

Pseudomonas aeruginosa resistance to fluoroquinolones involves more than just DNA-gyrase changes. Outer membrane protein alterations and efflux pump variations also contribute to this critical antibiotic resistance mechanism.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Molecular Biology

Background:

  • Pseudomonas aeruginosa is a significant cause of nosocomial infections.
  • This bacterium exhibits intrinsic and acquired resistance to antibiotics, complicating treatment.
  • Fluoroquinolones are used for P. aeruginosa infections, but resistance can emerge.

Purpose of the Study:

  • To investigate the mechanisms of fluoroquinolone resistance in Pseudomonas aeruginosa.
  • To analyze outer membrane protein (OMP) profiles, DNA polymorphism, and efflux pump presence.

Main Methods:

  • Studied six strains of P. aeruginosa.
  • Utilized electrophoresis for outer membrane protein (OMP) analysis.
  • Employed random amplified polymorphic DNA (RAPD) and polymerase chain reaction (PCR) for genetic analysis.

Main Results:

  • Identified alterations in outer membrane proteins (OMPs) in resistant strains.
  • Observed variations in DNA patterns suggesting genetic changes.
  • Found that resistance is linked to DNA-gyrase modifications, membrane changes, and efflux pump characteristics (qualitative and quantitative).

Conclusions:

  • Fluoroquinolone resistance in P. aeruginosa is multifactorial.
  • Mechanisms include DNA-gyrase modifications, alterations in membrane proteins, and the presence/activity of efflux pumps.
  • Understanding these mechanisms is crucial for effective antibiotic therapy against P. aeruginosa.

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