Characterization of emeA, a norA homolog and multidrug resistance efflux pump, in Enterococcus faecalis

被引：91
作者：
Jonas, BM
Murray, BE
Weinstock, GM
机构：
[1] Univ Texas, Sch Med, Dept Microbiol & Mol Genet, Houston, TX 77030 USA
[2] Univ Texas, Sch Med, Ctr Study Emerging & Reemerging Pathogens, Houston, TX 77030 USA
[3] Univ Texas, Sch Med, Div Infect Dis, Houston, TX 77030 USA
来源：
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY | 2001年 / 45卷 / 12期
关键词：
D O I：
10.1128/AAC.45.12.3574-3579.2001
中图分类号：
Q93 [微生物学];
学科分类号：
071005 ; 100705 ;
摘要：
We hypothesized that multidrug resistance efflux pumps (MDRs) may be contributing to the drug resistance of enterococci. We recently identified potential MDR-encoding genes in the Enterococcus faecalis V583 genome. Among the putative MDRs, we found a gene that encodes a NorA homolog and have characterized this enterococcal MDR in the present study. A mutant from which the enterococcal NorA homolog has been deleted has reduced resistance to several NorA substrates. Complementation of the deletion mutant with the wild-type gene verified the involvement of this enterococcal gene in resistance to ethidium bromide (EtBr) and norfloxacin. Known MDR inhibitors (reserpine, lansoprazole, and verapamil) inhibit the efflux of EtBr and norfloxacin in wild-type strain OG1RF. A fluorescence assay with EtBr allowed us to quantitate the efflux capability of the enterococcal NorA pump. On the basis of these results, we have named this enterococcal gene emeA (enterococcal multidrug resistance efflux).
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页码：3574 / 3579
页数：6
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