High‐Level Fluoroquinolone Resistance in Pseudomonas aeruginosa Due to Interplay of the MexAB‐OprM Efflux Pump and the DNA Gyrase Mutation

@article{Nakajima2002HighLevelFR,
  title={High‐Level Fluoroquinolone Resistance in Pseudomonas aeruginosa Due to Interplay of the MexAB‐OprM Efflux Pump and the DNA Gyrase Mutation},
  author={Akira Nakajima and Y Sugimoto and Hiroshi Yoneyama and Taiji Nakae},
  journal={Microbiology and Immunology},
  year={2002},
  volume={46}
}
Fluoroquinolone resistance in Pseudomonas aeruginosa is mainly attributable to the constitutive expression of the xenobiotic efflux pump and mutation in DNA gyrase or topoisomerase IV. We constructed cells with a double‐mutation in gyrA and mexR encoding DNA gyrase and repressor for the mexAB‐oprM operon, respectively. The mutant showed 1,024 times higher fluoroquinolone resistance than cells lacking the MexAB‐OprM. Cells with a single mutation in gyrA and producing a wild‐type level of the… Expand
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