Molecular Cloning and Characterization of an ABC Multidrug Efflux Pump, VcaM, in Non-O1 Vibrio cholerae
AUTOR(ES)
Huda, Nazmul
FONTE
American Society for Microbiology
RESUMO
A gene responsible for multidrug resistance was cloned from the chromosomal DNA of non-O1 Vibrio cholerae NCTC 4716 by using as a host drug-hypersensitive Escherichia coli strain KAM32, which lacks major multidrug efflux pumps. E. coli cells transformed with the gene showed elevated levels of resistance to a number of structurally dissimilar drugs, such as tetracycline, norfloxacin, ciprofloxacin, doxorubicin, daunomycin, 4′,6-diamidino-2-phenylindole, and Hoechst 33342. We determined the nucleotide sequence and found one open reading frame. We designated the gene vcaM. The deduced product, VcaM, seems to be a polypeptide with 619 amino acid residues (69 kDa) that has a putative topology of six transmembrane segments in the N-terminal hydrophobic domain, followed by an ATP binding domain in the C-terminal hydrophilic region. The sequence of VcaM was shown to be similar to those of human multidrug resistance proteins P-glycoprotein MDR1 and lactococcal LmrA, which are driven by ATP. The efflux of Hoechst 33342 and doxorubicin from cells possessing VcaM was detected. The efflux activity was inhibited by reserpine and sodium o-vanadate, which are potent inhibitors of MDR1 and LmrA. Thus, we conclude that VcaM is a member of the family of multidrug efflux pumps of the ATP binding cassette type and the first experimentally proven example of a multidrug efflux pump of this family in gram-negative bacteria.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=166069Documentos Relacionados
- Purification and characterization of Vibrio cholerae non-O1 heat-stable enterotoxin.
- Purification and characterization of pili of a Vibrio cholerae non-O1 strain.
- R plasmids in environmental Vibrio cholerae non-O1 strains.
- Molecular epidemiology of non-O1 Vibrio cholerae and Vibrio mimicus in the U.S. Gulf Coast region.
- Comparative study of Vibrio cholerae non-O1 protease and soluble hemagglutinin with those of Vibrio cholerae O1.