Expression of Pseudomonas aeruginosa multidrug efflux pumps MexA-MexB-OprM and MexC-MexD-OprJ in a multidrug-sensitive Escherichia coli strain

被引:147
作者
Srikumar, R
Kon, T
Gotoh, N
Poole, K [1 ]
机构
[1] Queens Univ, Dept Microbiol & Immunol, Kingston, ON K7L 3N6, Canada
[2] Kyoto Pharmaceut Univ, Dept Microbiol, Kyoto 607, Japan
关键词
D O I
10.1128/AAC.42.1.65
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
The mexCD-oprJ and mexAB-oprM operons encode components of two distinct multidrug efflux pumps in Pseudomonas aeruginosa. To assess the contribution of individual components to antibiotic resistance and substrate specificity, these operons and their component genes were cloned and expressed in Escherichia coli. Western immunoblotting confirmed expression of the P. aeruginosa efflux pump components in E. coli strains expressing and deficient in the endogenous multidrug efflux system (AcrAB), although only the Delta acrAB strain, KZM120, demonstrated increased resistance to antibiotics in the presence of the P. aeruginosa efflux genes. E. coli KZM120 expressing MexAB-OprM showed increased resistance to quinolones, chloramphenicol, erythromycin, azithromycin, sodium dodecyl sulfate (SDS), crystal violet, novobiocin, and, significantly, several beta-lactams, which is reminiscent of the operation of this pump in P. aeruginosa. This confirmed previous suggestions that MexAB-OprM provides a direct contribution to beta-lactam resistance via the efflux of this group of antibiotics. An increase in antibiotic resistance, however, was not observed when MexAB or OprM alone was expressed in KZM120. Thus, despite the fact that beta-lactams act within the periplasm, OprM alone is insufficient to provide resistance to these agents. E. coli KZM120 expressing MexCD-OprJ also showed increased resistance to quinolones, chloramphenicol, macrolides, SDS, and crystal violet, though not to most beta-lactams or novobiocin, again somewhat reminiscent of the antibiotic resistance profile of MexCD-OprJ-expressing strains of P. aeruginosa. Surprisingly, E. coli KZM120 expressing MexCD alone also showed an increase in resistance to these agents, while an OprJ-expressing KZM120 failed to demonstrate any increase in antibiotic resistance. MexCD-mediated resistance, however, was absent in a tolC mutant of KZM120, indicating that MexCD functions in KZM120 in conjunction with TolC, the previously identified outer membrane component of the AcrAB-TolC efflux system. These data confirm that a tripartite efflux pump is necessary for the efflux of all substrate antibiotics and that the P. aeruginosa multidrug efflux pumps are functional and retain their substrate specificity in E. coli.
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页码:65 / 71
页数:7
相关论文
共 45 条
[1]  
Benz R, 1993, J BACTERIOL, V178, P5803
[2]   Conservation of the multidrug resistance efflux gene oprM in Pseudomonas aeruginosa [J].
Bianco, N ;
Neshat, S ;
Poole, K .
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 1997, 41 (04) :853-856
[3]   INVIVO CLONING OF PSEUDOMONAS-AERUGINOSA GENES WITH MINI-D3112 TRANSPOSABLE BACTERIOPHAGE [J].
DARZINS, A ;
CASADABAN, MJ .
JOURNAL OF BACTERIOLOGY, 1989, 171 (07) :3917-3925
[4]  
EVANS K, UNPUB
[5]   Evidence that TolC is required for functioning of the Mar/AcrAB efflux pump of Escherichia coli [J].
Fralick, JA .
JOURNAL OF BACTERIOLOGY, 1996, 178 (19) :5803-5805
[6]   NEW NORFLOXACIN RESISTANCE GENE IN PSEUDOMONAS-AERUGINOSA PAO [J].
FUKUDA, H ;
HOSAKA, M ;
HIRAI, K ;
IYOBE, S .
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 1990, 34 (09) :1757-1761
[7]   THE OUTER-MEMBRANE PROTEIN OPRM OF PSEUDOMONAS-AERUGINOSA IS ENCODED BY OPRK OF THE MEXA-MEXB-OPRK MULTIDRUG-RESISTANCE OPERON [J].
GOTOH, N ;
TSUJIMOTO, H ;
POOLE, K ;
YAMAGISHI, JI ;
NISHINO, T .
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 1995, 39 (11) :2567-2569
[8]   ISOLATION OF OPRM-DEFICIENT MUTANTS OF PSEUDOMONAS-AERUGINOSA BY TRANSPOSON INSERTION MUTAGENESIS - EVIDENCE OF INVOLVEMENT IN MULTIPLE ANTIBIOTIC-RESISTANCE [J].
GOTOH, N ;
ITOH, N ;
TSUJIMOTO, H ;
YAMAGISHI, J ;
OYAMADA, Y ;
NISHINO, T .
FEMS MICROBIOLOGY LETTERS, 1994, 122 (03) :267-273
[9]   RESISTANCE OF NEISSERIA-GONORRHOEAE TO ANTIMICROBIAL HYDROPHOBIC AGENTS IS MODULATED BY THE MTRRCDE EFFLUX SYSTEM [J].
HAGMAN, KE ;
PAN, WB ;
SPRATT, BG ;
BALTHAZAR, JT ;
JUDD, RC ;
SHAFER, WM .
MICROBIOLOGY-SGM, 1995, 141 :611-622
[10]   MUTATIONS PRODUCING RESISTANCE TO NORFLOXACIN IN PSEUDOMONAS-AERUGINOSA [J].
HIRAI, K ;
SUZUE, S ;
IRIKURA, T ;
IYOBE, S ;
MITSUHASHI, S .
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 1987, 31 (04) :582-586