Genomic comparison of Fluoroquinolone resistant and susceptible outbreak strains of Stenotrophomonas maltophilia. Stenotrophomonas maltophilia stmalt0435

Stenotrophomonas maltophilia is an emerging, multi drug resistant nosocomial pathogen. Besides co-trimoxazole, fluoroquinolones are generally used as for treatment. Although one major clinical concern is the appearance of drug resistant strains limiting the choice of antimicrobial drugs. During large outbreaks changes in the antimicrobial susceptibility of the outbreak strains have repeatedly been observed. In contrast to other nosocomial pathogens the fluoroquinolone-resistance in S. maltophilia is not caused by the usual mutations in the gyrase or topoisomerase encoding genes. Pairs of outbreak strains, which were genetically related according to their Amplified Fragment Length Polymorphism, were selected on the base of an at least 8-fold difference of their Minimum Inhibitory Concentration (MIC) against ciprofloxacin and moxifloxacin. Draft genomes of such a pair of fluoroquinolone resistant and susceptible strains of S.maltophilia were sequenced employing high throughput sequencing approach (Hiseq 2000) and compared, as a result single nucleotide polymorphism within potential antimicrobial associated genes were observed