Real-time PCR assays were developed for the enumeration of plasmid-mediated quinolone resistance (PMQR) determinants, such as the qnrA, qnrB, and qnrS genes, in different water samples and chicken feces. The results indicate that the developed assays are specific and sensitive for the quantification of qnr genes in complex samples.

background: emergence klebsiella pneumoniae resistant to quinolone antibiotics due to mutations in gyra and parc genes created problem for treatment of patients in different hospitals in iran. the objective of this study was to determine the amino acid substitutions of gyra and parc proteins in certain clonal lineages of the k. pneumoniae conferring high level quinolone resistance. methods: one...

Quinolones are a large and widely consumed class of synthetic drugs. Expanded-spectrum quinolones, like ciprofloxacin are highly effective against Gram-negative bacteria, especially Escherichia coli. In E. coli the major target for quinolones is DNA gyrase. This enzyme is composed of two subunits, GyrA and GyrB encoding by gyrA and gyrB, respectively. Mutations in either of these genes cause qu...

Escherichia coli NB8 is a clinical pyelonephritis isolate. Here, we report the draft genome sequence of uropathogenic E. coli NB8, which contains drug resistance genes encoding resistance to beta-lactams, aminoglycosides, quinolones, macrolides, colistin, sulfonamide-trimethoprim, and tetracycline. NB8 infects the kidney and bladder, making it an important tool for studying E. coli pathogenesis.

As a result of the increasing resistance of Helicobacter pylori against first-line antibiotics, other drugs, such as quinolones, will be needed for eradication therapy in the future. We developed a real-time PCR to detect mutations in the gyrA gene associated with ciprofloxacin resistance of H. pylori, thereby contributing to the selection of patients who could be treated by ciprofloxacin-based...

A panel of 266 clinically isolated Gram-positive cocci and Gram-negative bacilli with varying levels of resistance to ciprofloxacin were analysed for susceptibility to Du-6859a, ciprofloxacin, ofloxacin, temafloxacin and nalidixic acid. Staphylococci were divided into ciprofloxacin-susceptible, moderately resistant and highly resistant subgroups. Du-6859a was the most potent quinolone against a...

OBJECTIVES The aim of this study was to estimate the frequency of triple- and quadruple-resistant Helicobacter pylori isolated in Germany, to characterize those isolates molecular genetically and to identify risk factors for the development of multiresistance. METHODS Antimicrobial susceptibility to metronidazole, clarithromycin, amoxicillin, tetracycline, ciprofloxacin/levofloxacin and rifam...

BACKGROUND Plasmid mediated quinolone resistance (PMQR) has been shown to play an important role in resistance not only to quinolones, but also β-lactams and aminoglycosides. In fact, qnr genes are frequently carried along with β-lactamase determinants on the same plasmids. We studied the prevalence of qnrA, qnrB, qnrS and aac(6')-Ib-cr genes among quinolone and cephalosporin resistant clinical...

OBJECTIVES The aim of this study was to update data on levofloxacin/ciprofloxacin and triple resistance (resistance to metronidazole, clarithromycin and levofloxacin/ciprofloxacin) in Helicobacter pylori clinical isolates and to identify the impact of prior eradication therapies on their development. METHODS We tested the antimicrobial susceptibility to amoxicillin, metronidazole, clarithromy...