| Title |
Inactivation of MuxABC-OpmB Transporter System in Pseudomonas aeruginosa Leads to Increased Ampicillin and Carbenicillin Resistance and Decreased Virulence |
| Author |
Liang Yang1, Lin Chen1, Lixin Shen1, Michael Surette2, and Kangmin Duan1,3* |
| Address |
1Molecular Microbiology Laboratory, Key Laboratory of Resources Biology and Biotechnology in Western China, Ministry of Education, Faculty of Life Sciences, Northwest University, Shaanxi 710069, P. R. China, 2Department of Microbiology and Infectious Diseases, Faculty of Medicine, University of Calgary, 3330 Hospital Dr. NW, Calgary AB T2N 4N1, Canada, 3Department of Oral Biology, Faculty of Dentistry, University of Manitoba, 780 Bannatyne Ave. Winnipeg, MB R3E OW2, Canada |
| Bibliography |
Journal of Microbiology, 49(1),107-114, 2011,
|
| DOI |
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| Key Words |
MuxABC-OpmB, β-lactam resistance, virulence, twitching motility, P. aeruginosa |
| Abstract |
Resistance-Nodulation-Cell Division (RND) pumps play important roles in bacterial resistance to antibiotics. Pseudomonas aeruginosa is an important human pathogen which exhibits high level resistance to antibiotics. There are total of 12 RND pumps present in the P. aeruginosa PAO1 genome. The recently characterized MuxABC-OpmB system has been shown to play a role in resistance to novobiocin, aztreonam, macrolides, and tetracycline in a multiple knockout mutation. In this study, we examined the expression levels of all the 12 RND pump gene clusters and tested the involvement of MuxABC-OpmB in pathogenicity. The results indicated that in addition to the four known constitutively expressed RND pumps, mexAB-oprM, mexGHIopmD, mexVW, and mexXY, relatively high levels of expression were observed with mexJK and muxABCopmB in the conditions tested. Inactivation of muxA in the muxABC-opmB operon resulted in elevated resistance to ampicillin and carbenicillin. The mutant also showed attenuated virulence in both Brassica rapa
pekinensis and Drosophila melanogaster infection models. The decreased virulence at least in part was due to decreased twitching motility in the mutant. These results indicate that the RND pump MuxABC-OpmB is associated with ampicillin and carbenicillin susceptibility and also involved in pathogenesis in P. aeruginosa. |
