Measuring Small Molecule Binding to Escherichia coli AcrB by Surface Plasmon Resonance
Antimicrobial resistance (AMR) is rapidly becoming one of the great healthcare challenges. A common mechanism employed by pathogenic bacteria to avoid the action of certain antibiotics is to overexpress efflux pumps that can extrude these drugs from the cell rendering them ineffective. Small molecule inhibitors that target bacterial efflux pumps provide a route toward reversing AMR. Here, we describe the application of surface plasmon resonance (SPR) technology to characterize protein:small molecule interactions between the inner membrane protein AcrB subunit of the Escherichia coli AcrA-AcrB-TolC efflux pump and its substrates and novel inhibitors. The SPR assay provides quantitative data about the kinetics of binding that can help guide the development of new chemotherapies to combat AMR.
Key wordsSurface plasmon resonance Binding kinetics Small molecule Efflux pumps Antimicrobial resistance Antibiotic discovery AcrA-AcrB-TolC Efflux pump inhibitors
This research was supported financially by the National Natural Science Foundation of China (81673284), National Health and Medical Research Council of Australia (GN1147538), China–Australia Centre for Health Sciences Research and Australian Postgraduate Award (RM). All experiments were performed on a BiaCore 200 which from part of the Biophysical Characterisation Suite at The University of South Australia.
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