Ninety-three Malaysian extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae isolates were investigated for ciprofloxacin resistance. Two mismatch amplification mutation (MAMA) assays were developed and used to facilitate rapid detection of gyrA and parC mutations. The isolates were also screened for plasmid-mediated quinolone resistance (PMQR) genes including aac(6')-Ib-cr, qepA...

This work studies the performance of a cooperative network which consists of two channel-coded sources, multiple relays, and one destination. To achieve high spectral efficiency, we assume that a single time slot is dedicated to relaying. Conventional network-coded-based cooperation (NCC) selects the best relay which uses network coding to serve the two sources simultaneously. The bit error rat...

The mechanism of quinolone resistance in Mycoplasma genitalium remains poorly understood due to difficulties with in vitro culture, especially of clinical isolates. In this study, to confirm the association between mutations in topoisomerases and antimicrobial susceptibilities to quinolones, ciprofloxacin-resistant mutant strains were selected using the cultivable type strain ATCC 33530. Sequen...

In Bacillus subtilis, parE and parC were shown to be essential genes for the segregation of replicated chromosomes. Disruption of either one of these genes resulted in failure of the nucleoid to segregate. Purified ParE and ParC proteins reconstituted to form topoisomerase IV (topo IV), which was highly proficient for ATP-dependent superhelical DNA relaxation and decatenation of interlocked DNA...

OBJECTIVES To study the role of TolC and of parC mutation in high-level fluoroquinolone resistance in clonal clinical strains of Salmonella enterica serotype Typhimurium phage type DT204 (S. Typhimurium DT204). METHODS Deletion of the tolC gene (DeltatolC) was first performed in a susceptible S. Typhimurium DT104 strain lacking target gene mutations involved in fluoroquinolone resistance. P22...

Molecular characterization of fluoroquinolone-resistant Streptococcus pneumoniae in Canada was conducted from 1997 to 2005. Over the course of the study, 205 ciprofloxacin-resistant isolates were evaluated for ParC and GyrA quinolone resistance-determining region (QRDR) substitutions, substitutions in the full genes of ParC, ParE, and GyrA, reserpine sensitivity, and serotype and by pulsed-fiel...

Resistance to fluoroquinolone (FQ) antibiotics in Streptococcus pneumoniae has been attributed primarily to specific mutations in the genes for DNA gyrase (gyrA and gyrB) and topoisomerase IV (parC and parE). Resistance to some FQs can result from a single mutation in one or more of the genes encoding these essential enzymes. A group of 160 clinical isolates of pneumococci was examined in this ...

Authors' A Marseille-L Correspon Parc Scien 33-0-4-91univ-mrs.fr