As a representative fluoroquinolone antibacterial, ciprofloxacin is frequently used to treat infections caused by bacteria such as E. coli. It is much meaningful to explore ciprofloxacin susceptibility and investigate a possible mechanism of drug susceptibility changes in E. coli ATCC25922 exposed to the environmental stress of simulated microgravity. The subculture of E. coli lasted for 7 days...

Detection of azide-tagged biomolecules (e.g., azido sugars) inside living cells using “click” chemistry has been revolutionary to the field chemical biology. However, we currently still lack suitable synthetic biology tools autonomously and rapidly detect azide ions. Here, have developed an engineered promoter system called cyn regulon, complementary Escherichia coli strains, selectively ions i...

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...

Background: Multidrug-resistant efflux pumps are one of the most significant methods by which bacteria can evade effects numerous antimicrobials. The aim this study was to determine prevalence multidrug-resistant MDR, extremely drug-resistant XDR, and pan-drug-resistant PDR K. pneumoniae phenotypes in clinical isolates, as well examine detection pump genes ompK35, ompK36, tolC, acrAB strains.&#...

OBJECTIVES Hfq is a bacterial RNA chaperone involved in the post-transcriptional regulation of many stress-inducible genes via small non-coding RNAs. Although Hfq is related to important phenotypes including virulence in many bacterial pathogens, its role in drug resistance is unknown. The aim of this study was to investigate the role of Hfq in bacterial multidrug resistance. METHODS The hfq ...

Members of the resistance-nodulation-division (RND) family of efflux pumps, such as AcrAB-TolC of Escherichia coli, play major roles in multidrug resistance (MDR) in Gram-negative bacteria. A strategy for combating MDR is to develop efflux pump inhibitors (EPIs) for use in combination with an antibacterial agent. Here, we describe MBX2319, a novel pyranopyridine EPI with potent activity against...

OmpR is a transcriptional regulator implicated in the control of various cellular processes and functions in Enterobacteriaceae. This study was undertaken to identify genes comprising the OmpR regulon in the human gastrointestinal pathogen Yersinia enterocolitica. Derivatives of an ompR-negative strain with random transposon insertions creating transcriptional fusions with the reporter gene lac...

Erwinia amylovora causes fire blight on several plant species such as apple and pear, which produce diverse phytoalexins as defence mechanisms. An evolutionary successful pathogen thus must develop resistance mechanisms towards these toxic compounds. The E. amylovora outer membrane protein, TolC, might mediate phytoalexin resistance through its interaction with the multidrug efflux pump, AcrAB....

The relationship between efflux system overexpression and cross-resistance to cefoxitin, quinolones, and chloramphenicol has recently been reported in Klebsiella pneumoniae. In 3 previously published clinical isolates and 17 in vitro mutants selected with cefoxitin or fluoroquinolones, mutations in the potential regulator genes of the AcrAB efflux pump (acrR, ramR, ramA, marR, marA, soxR, soxS,...

Resistance to fluoroquinolones has been recently increased among bacterial strains isolated from outpatients. Multidrug-resistant K. pneumoniae is one of the major organisms isolated from burn patients and the AcrAB efflux pump is the principal pump contributing to the intrinsic resistance in K. pneumoniae against multiple antimicrobial agents including ciprofloxacin and other fluoroquinolones....