Molecular characterization of fluoroquinolone resistance in clinical and environmental vibrio cholerae isolated from baghdad, iraq

The Gram-negative bacterium Vibrio cholerae is the etiologic agent of cholera. The ability of V. cholerae to colonize and cause disease in hosts requires production of a number of virulence factors during infection. A total of Forty clinical and environmental V. cholerae isolates have been isolated from different samples in Baghdad .The susceptibility to different antibiotics was evaluated by disk diffusion method and MICs were determined, All environmental isolates were sensitive (100%) to all antibiotics, while the clinical isolates were shown variable behavior against these antibiotics, these shown (90%) to ciprofloxacin, as a highest value and (50%) for amoxicillin as a lowest value, in other hand, these isolates revealeded resistance (100%) to nalidixic acid, ampicillin and Co-trimoxazole. The MICs values were 128-1024 μg/ml for clinical isolates. Polymerase Chain Reaction (PCR) was performed for detection of qnr VC3 gene in Vibrio cholerae isolates, the results showed that qnr VC3 gene didn’t appear in any isolate. The detection of of plasmid DNA by gel electrophoresis showed that some isolates carried more than one plasmid bands; the curing plasmids for isolates were appeared sensitivity against antibiotics that lead us to conclude that gene was carried on plasmid.