Detection of point mutations associated with antibiotic resistance in Pseudomonas aeruginosa

Int J Antimicrob Agents. 2009 Nov;34(5):414-8. doi: 10.1016/j.ijantimicag.2009.05.013. Epub 2009 Aug 4.

Abstract

Excessive use of broad-spectrum antibiotics in hospitals has led to the emergence of highly resistant strains of Pseudomonas aeruginosa. To reduce the selection pressure for resistance, it is important to determine the antibiotic susceptibility pattern of bacteria so that hospital patients can be treated with more narrow-spectrum and target-specific antibiotics. This study describes the development of a technique for detecting point muations in the fluoroquinolone resistance-determining region of the gyrA and parC genes as well as the efflux regulatory genes mexR, mexZ and mexOZ that are associated with fluoroquinolone and aminoglycoside resistance. The assay is based on a short DNA sequencing method using multiplex-fast polymerase chain reaction (PCR) and Pyrosequencing for amplification and sequencing of the selected genes. Fifty-nine clinical isolates of P. aeruginosa were examined for mutations in the abovementioned genes. Mutations related to antibiotic resistance were detected in codons 83 and 87 of gyrA and codon 126 of the mexR regulatory gene. Results of this study suggest Pyrosequencing as a substitute for traditional methods as it provides a rapid and reliable technique for determining the antibiotic resistance pattern of a given bacterial strain in <1 h.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aminoglycosides / pharmacology
  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics
  • DNA Gyrase
  • DNA Mutational Analysis
  • DNA Topoisomerase IV
  • DNA, Bacterial / genetics*
  • Drug Resistance, Bacterial*
  • Fluoroquinolones / pharmacology
  • Humans
  • Microbial Sensitivity Tests / methods*
  • Point Mutation*
  • Polymerase Chain Reaction / methods
  • Pseudomonas Infections / microbiology
  • Pseudomonas aeruginosa / drug effects*
  • Pseudomonas aeruginosa / genetics*
  • Pseudomonas aeruginosa / isolation & purification
  • Repressor Proteins / genetics
  • Sequence Analysis, DNA / methods

Substances

  • Aminoglycosides
  • Anti-Bacterial Agents
  • Bacterial Proteins
  • DNA, Bacterial
  • Fluoroquinolones
  • MexR protein, Pseudomonas aeruginosa
  • MexZ protein, Pseudomonas aeruginosa
  • Repressor Proteins
  • DNA Topoisomerase IV
  • DNA Gyrase