A multidrug efflux pump gene (cmeB) was identified from the published Campylobacter jejuni genome sequence. Secondary structural analysis showed that the gene encoded a protein belonging to the resistance nodulation cell division (RND) family of efflux transporters. The gene was inactivated by insertional mutagenesis. Compared with the wild-type strain (NCTC 11168), the resultant knockout strain (NCTC 11168-cmeB::kan(r)) displayed increased susceptibility to a range of antibiotics including beta-lactams, fluoroquinolones, macrolides, chloramphenicol, tetracycline, ethidium bromide, the dye acridine orange and the detergent sodium dodecyl sulfate. Accumulation of ciprofloxacin was increased in the knockout mutant, but carbonyl cyanide m-chlorophenyl hydrazone, a proton motive force inhibitor, had less effect upon ciprofloxacin accumulation in the knockout mutant compared with NCTC 11168. These data show that the identified gene encodes an RND-type multi-substrate efflux transporter, which contributes to intrinsic resistance to a range of structurally unrelated compounds in C. jejuni. This efflux pump has been named CmeB (for Campylobacter multidrug efflux).
|Number of pages||5|
|Journal||FEMS Microbiology Letters|
|Publication status||Published - 1 Jan 2002|
- multiple antibiotic resistance
- Campylobacter jejuni
- Campylobacter multidrug efflux B