Resistance to beta-lactam antibiotics in Pseudomonas aeruginosa due to interplay between the MexAB-OprM efflux pump and beta-lactamase

Citation
T. Nakae et al., Resistance to beta-lactam antibiotics in Pseudomonas aeruginosa due to interplay between the MexAB-OprM efflux pump and beta-lactamase, ANTIM AG CH, 43(5), 1999, pp. 1301-1303
Citations number
18
Categorie Soggetti
Microbiology
Journal title
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
ISSN journal
00664804 → ACNP
Volume
43
Issue
5
Year of publication
1999
Pages
1301 - 1303
Database
ISI
SICI code
0066-4804(199905)43:5<1301:RTBAIP>2.0.ZU;2-X
Abstract
We evaluated the roles of the MexAB-OprM efflux pump and beta-lactamase in beta-lactam resistance in Pseudomonas aeruginosa by constructing OprM-defic ient, OprM basal level, and OprM fully expressed mutants from beta-lactamas e-negative, -inducible, and -overexpressed strains. We conclude that, with the notable exception of imipenem, the MexAB-OprM pump contributes signific antly to beta-lactam resistance in both beta-lactamase-negative and beta-la ctamase-inducible strains, while the contribution of the MexAB-OprM efflux system is negligible in strains with overexpressed beta-lactamase. Overexpr ession of the efflux pump alone contributes to the high level of beta-lacta m resistance in the absence of beta-lactamase.