Screening of random fragments of Escherichia coli genomic DNA for their ability to increase the novobiocin resistance of a hypersusceptible (Delta)acrAB mutant resulted in the isolation of a plasmid containing baeR, which codes for the response regulator of the two-component regulatory system BaeSR. When induced for expression, baeR cloned in multicopy plasmid pTrc99A significantly increased th...

OBJECTIVES We investigated the antimicrobial susceptibilities and resistance mechanisms of cattle-adapted Salmonella enterica serovar Dublin isolated in Japan in the past 30 years. This study is an example of evaluation of the impact of introduction of antimicrobials in veterinary medical practice on the selection of resistance in S. enterica. METHODS The antimicrobial susceptibilities and pr...

background in recent decades, bacterial antibiotic resistance (especially in enterococci) has become a significant problem for human and veterinary medicine. one of the most important antibiotic resistances in enterococci, vancomycin resistance, is encoded by van gene family. objectives the aim of this study was to investigate antibiotic resistance to vancomycin in enterococci and the genes res...

The AcrAB/TolC efflux pump-mediated drug resistance in gram-negative bacteria might be controlled by pump inhibitors (EPIs). This study was planned to discover a compound from plants that can used as an EPI. Forty isolates of K. pneumoniae and 33 different were collected. methanolic extracts parts prepared. Chloramphenicol, tetracycline, Ciprofloxacin for the sensitivity assay. Plant tested EPI...

This study aims to compare the resistance phenotypes conferred by various genes encoding enzymes that phosphorylate erythromycin. The mph genes were cloned into Escherichia coli AG100A susceptible to macrolides and ketolides following disruption of the AcrAB pump. An 882 bp sequence containing a premature stop codon, homologous to the three other previously described mph genes and present widel...

MarA47(Yp) from Yersinia pestis, showing 47% identity to Escherichia coli MarA in its N terminus, caused resistance to antibiotics and to organic solvents when expressed in both E. coli and Y. pestis. Resistance was linked to increased expression of the AcrAB multidrug efflux pump. In four of five spontaneous multidrug-resistant mutants of Y. pestis independently selected by growth on tetracycl...

AAC03727-14R1 1 2 Moraxella catarrhalis AcrAB-OprM efflux pump contributes to antimicrobial 3 resistance and is enhanced during the cold shock response 4 5 6 7 Violeta Spaniol, Sara Bernhard, Christoph Aebi 8 9 10 Institute for Infectious Diseases, University of Bern, CH-3010 Bern, Switzerland, 11 Department of Pediatrics, University of Bern, Inselspital, CH-3010 Bern, Switzerland 12 13 14 Runn...

Seven Klebsiella pneumoniae and four Klebsiella oxytoca clinical isolates with different levels of resistance to ciprofloxacin were studied. Mutations in the topoisomerase genes were found in almost all strains, but the contribution of a multidrug efflux system homologous to AcrAB in Escherichia coli was also observed. Overexpression of this efflux system was demonstrated by immunoblotting with...

Objective: Overexpression of AcrAB-TolC protein complex is often associated with the virulence of multidrug-resistant bacteria. Development of an effective efflux pump inhibitors (EPI) can be a major strategy to enhance the effectivity of current antibiotics and to restrain the menace of antibiotic resistance among bacteria. Molecular docking based assessment of anticancer drugs as EPI with com...

BACKGROUND Haemophilus influenzae HMC-C with high-level macrolide resistance after multi-step selection by clarithromycin reverted spontaneously and became hypersusceptible to macrolides. OBJECTIVE Determination of macrolide resistance mechanism(s) in hypersusceptible and hyperresistant strains. METHODS The presence of macrolide efflux in the strains was studied by radioactive erythromycin ...