Reduced susceptibility to antimicrobials in Gram-negative bacteria may result from multiple resistance mechanisms, including increased efflux pump activity or reduced porin protein expression. Up-regulation of the efflux pump system is closely associated with multidrug resistance (MDR). To help investigate the role of efflux pumps on compound accumulation, a fluorescence-based assay was develop...

Efflux pump mechanisms perform important physiological functions such as prevention of toxin absorption from the gastrointestinal tract, elimination of bile from the hepatocytes, effective functioning of the blood-brain barrier and placental barrier, and renal excretion of drugs. They exist in all living cells, but those in the bacterial and mammalian cells are more important to the clinician a...

Efflux pump mechanisms perform important physiological functions such as prevention of toxin absorption from the gastrointestinal tract, elimination of bile from the hepatocytes, effective functioning of the blood–brain barrier and placental barrier, and renal excretion of drugs. They exist in all living cells, but those in the bacterial and mammalian cells are more important to the clinician a...

OBJECTIVES This study was conducted to examine the role of the CmeABC efflux pump in decreasing the susceptibility of Campylobacter coli to macrolides and ketolides in the context of absence or presence of mutations in the 23S rRNA genes. METHODS The cmeB gene was inactivated in strains of C. coli showing two different patterns of erythromycin resistance (low or high level of resistance) asso...

OBJECTIVES To study the potential factors include gene mutation, efflux pump and alteration of permeability associated with quinolone-resistance of Salmonella enterica strains isolated from patients with acute gastroenteritis and to evaluate the degree of synergistic activity of efflux pump inhibitors when combined with ciprofloxacin against resistant isolates. METHODS Antimicrobial resistanc...

  Target modification and reduced drug accumulation are the main resistance mechanisms against fluoroquinolone antibiotics in Pseudomonas aeruginosa. We performed a genotypic characterization of three major Mex multidrug efflux pumps (MexAB-OprM, MexXY-OprM and MexCD-OprJ) in ciprofloxacin resistant clinical isolates of P. aeru­ginosa, collected from Tehran, Iran this was followed by sequencin...

We evaluated the contributions of Mycobacterium tuberculosis efflux pumps towards intrinsic resistance to different classes of peptidoglycan synthesis inhibitors (PSI). Our study indicates that the efflux pump knockout strains are more susceptible to PSI than the wild type. Vancomycin and ceftriaxone exhibited up to 3 log increased kill on efflux pump mutants compared to the wild-type strain, s...

ba ckground: legionella pneumophila is  a  dangerous pathogenic bacterium can cause serious infectious diseases especially in hospitalized immuno-compromised patients. this bacterium is shown to be resistant against different antibiotics. resistance against a wide range of antibiotics is usually mediated by efflux pump in bacteria. efflux pumps are proteinaceous transporters localized in the cy...