Gene cloning and properties of the RND-type multidrug efflux pumps MexPQ-OpmE and MexMN-OprM from Pseudomonas aeruginosa

Takehiko Mima, Hiroshi Sekiya, Tohru Mizushima, Teruo Kuroda, Tomofusa Tsuchiya

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42 Citations (Scopus)


We cloned two operons for putative RND-type multidrug efflux pumps from Pseudomonas aeruginosa by a PCR method. We designated the genes in one operon mexPQ(-opmE) and in another operon mexMN. Introduction of the mexPQ-opmE into drug hypersensitive cells resulted in elevated MICs of macrolides, fluoroquinolones and some other drugs. Introduction of the mexMN into the hypersensitive cells possessing oprM, but not into cells not possessing oprM, resulted in elevated MICs of chloramphenicol and thiamphenicol. Thus, we conclude that MexPQ-OpmE and MexMN-OprM are functional multidrug efflux pumps when expressed in P. aeruginosa.

Original languageEnglish
Pages (from-to)999-1002
Number of pages4
JournalMicrobiology and Immunology
Issue number11
Publication statusPublished - 2005 Jan 1



  • MexMN
  • MexPQ
  • Multidrug efflux pumps
  • P. aeruginosa

ASJC Scopus subject areas

  • Microbiology
  • Immunology
  • Virology

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