Multidrug Efflux Pumps from Enterobacteriaceae, Vibrio cholerae and Staphylococcus aureus Bacterial Food Pathogens

Abstract

Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations.

Resistance to β-lactam and tetracycline in Campylobacter spp.isolated from broiler slaughterhouses in southern Brazil

“…It is also possible that, in some species, efflux pumps that export antimicrobial agents also export virulence determinants, such as adhesins, toxins or other proteins that are important for the colonization and infection of human and animal cells (Piddock 2006). The role of efflux pumps in biofilm formation, persistence, resistance to antimicrobials and biocides was largely hypothetical; until some recent studies have discovered that expression of efflux pumps contribute to antimicrobial resistance by biofilms (Zhang & Mah 2008, Andersen et al 2015. The higher expression of efflux pumps offers physiological advantage in the form of expelling toxic wastes from the densely populated biofilms and in the process efflux antimicrobial compounds, which is manifested as enhanced antimicrobial resistances of biofilms (Andersen et al 2015).…”

“…The role of efflux pumps in biofilm formation, persistence, resistance to antimicrobials and biocides was largely hypothetical; until some recent studies have discovered that expression of efflux pumps contribute to antimicrobial resistance by biofilms (Zhang & Mah 2008, Andersen et al 2015. The higher expression of efflux pumps offers physiological advantage in the form of expelling toxic wastes from the densely populated biofilms and in the process efflux antimicrobial compounds, which is manifested as enhanced antimicrobial resistances of biofilms (Andersen et al 2015). In addition, adaptation to the environment, such as quorum sensing and biofilm formation can also contribute to bacterial persistence (Martins et al 2013).…”

Modulation of the multidrug efflux pump EmrD-3 from Vibrio cholerae by Allium sativum extract and the bioactive agent allyl sulfide plus synergistic enhancement of antimicrobial susceptibility by A. sativum extract

“…The causative agent of cholera disease, Vibrio cholerae, a Gram-negative bacterium has evolved several mechanisms to resist antimicrobial agents prescribed to treat severe cases, thereby marginalizing their chemotherapeutic efficacies (Ghosh and Ramamurthy 2011;Kitaoka et al 2011;Leibovici-Weissman et al 2014). Critical antimicrobial resistance mechanisms in V. cholerae include drug target alteration, drug-degrading enzymes, decreased drug permeability, and active drug efflux (Andersen et al 2015;Ghosh and Ramamurthy 2011;Kitaoka et al 2011).…”

“…Efflux pumps can be specific to transporting one substrate or multiple structurally diverse substrates (Andersen et al 2015;Kumar and Varela 2012;Levy 1989). These efflux pump systems lower the intracellular concentrations of antimicrobial agents, permitting the bacterium to survive in higher external concentrations of drugs thereby making diseasecausing bacteria more recalcitrant to treatment (Blair et al 2015).…”

Isolation of multidrug resistant coliforms and their bacteriophages from swine slurry

“…Reports show that strains of Salmonella spp. and E. coli may not only survive in this environment but also contain genes making them resistant to several medically important antibiotics such as norfloxacin, ampicillin, or extended-spectrum cephalosporins (7,8). Thus, it has been proven that slurry is a reservoir of antibiotic resistance genes (7).…”