Na+-driven multidrug efflux pump VcmA from Vibrio cholerae non-O1, a non-halophilic bacterium.
A chromosomal DNA fragment from Vibrio cholerae non-O1 containing a drug resistance determinant was cloned and sequenced. The deduced amino acid sequence suggested that the determinant gene encodes a multidrug efflux pump. We designated the pump VcmA. Escherichia coli cells transformed with a plasmid carrying the vcmA gene showed increased resistance against norfloxacin, ciprofloxacin, ofloxacin, daunomycin, doxorubicin, streptomycin, kanamycin, ethidium bromide, 4',6-diamidino-2-phenylindole dihydrochloride, Hoechst 33342 and acriflavine. Na+ (or Li+)-dependent efflux of ethidium bromide was detected in transformant cells. Efflux of Na+, elicited by ethidium bromide, was observed from transformant cells. Thus, we concluded that the VcmA is a Na+/drug antiporter.
Huda
M N
MN
Department of Microbiology, Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700-8530, Japan.
Morita
Y
Y
Kuroda
T
T
Mizushima
T
T
Tsuchiya
T
T
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004996:Ethidium / Q000378:metabolism; D005798:Genes, Bacterial; D026901:Membrane Transport Proteins; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D012964:Sodium / Q000378:metabolism*; D014734:Vibrio cholerae / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D026901:Membrane Transport Proteins; C439543:VcmA protein, Vibrio cholerae; D012964:Sodium; D004996:Ethidium