Efflux of chloramphenicol by the CmlA1 protein.
The cmlA1 gene cassette contains the cmlA1 gene, that confers resistance to chloramphenicol, as well as a promoter and translational attenuation signals, and expression of cmlA1 is inducible by low concentrations of chloramphenicol. The CmlA1 protein encoded by cmlA1 was localised in the inner membrane. Active efflux of chloramphenicol, additional to the endogenous efflux from Escherichia coli cells, was observed when the cmlA1 gene was present and the production of CmlA1 had been preinduced with subinhibitory concentrations of chloramphenicol. Both endogenous and CmlA1-mediated export of chloramphenicol was driven by the proton-motive force.
George
Anthony M
AM
Department of Cell and Molecular Biology, Faculty of Science, University of Technology Sydney, P.O. Box 123, Broadway, NSW 2007, Australia. tony.george@uts.edu.au
Hall
Ruth M
RM
D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002701:Chloramphenicol / Q000493:pharmacokinetics*; D002702:Chloramphenicol Resistance / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics; D010957:Plasmids / Q000235:genetics
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D004251:DNA Transposable Elements; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D002701:Chloramphenicol