Multiple Benefits of Plasmid-Mediated Quinolone Resistance Determinants in Klebsiella pneumoniae ST11 High-Risk Clone and Recently Emerging ST307 Clone

摘要: International high-risk clones of Klebsiella pneumoniae are among the most common nosocomial pathogens. Increased diversity plasmid-encoded antimicrobial resistance genes facilitates spread these causing significant therapeutic difficulties. The purpose our study was to investigate fluoroquinolone in extended-spectrum beta-lactamase (ESBL)-producing strains, including four K. and a single oxytoca, isolated from blood cultures Hungary. Whole-genome sequencing molecular typing multilocus sequence (MLST) pulsed-field gel electrophoresis (PFGE) were performed selected strains. Gene expression plasmid-mediated quinolone determinants (PMQR) investigated by quantitative-PCR. MLST revealed that three strains belonged ST11 one ST307 whereas oxytoca ST52. isolates harbored different β-lactamase however, all uniformly carried blaCTX-M-15. exhibited fluoroquinolones various PMQR namely, two harboured qnrB4, strain qnrB1 oqxAB efflux pump. Levofloxacin moxifloxacin MIC values correlated with qnr levels. qnrA1 carrying ST52 reduced susceptibility fluoroquinolones. maintained parallel chromosomal mutations indicate an additional protective role Qnr proteins can support dissemination clones. During development high-level resistance, retain fitness thus, enabling them for hospital environment. Based on knowledge this is first report clone Hungary, emerging as potential worldwide. High-level upregulated gene linked