fluoroquinolone-resistant clinical isolates. In conjunction with multiple mutations in gyrA and parC, altered OMPs and LPS, increased efflux and the presence of the qnr gene would favour the survival of DNA gyrase mutants as opposed to susceptible strains. This would facilitate the development of high-level resistance mutants in the clinical setting. Microorganisms are constantly evolving and their acquisition of a combination of beneficial mutations within target genes, in concert with a variety of OM modifications and efflux systems, would allow these versatile organisms to survive and reproduce in the face of antagonistic therapeutic agents