Photo-induced proton gradients for the in vitro investigation of bacterial efflux pumps

• DOI: 10.1038/srep00306
• Publication Date: 2012-03-07T10:03:31Z
• Authors: Alice Verchère; Isabelle Broutin; Martin Picard
• Keywords: Efflux; Electrochemical gradient; Proton Pump; Proton Transport; Chemiosmosis; Diaphragm pump

We describe an original activity assay for membrane transport that uses the proton motive force-dependent efflux pump MexAB from Pseudomonas aeruginosa. This is co-reconstituted into proteoliposomes together with bacteriorhodopsin (BR), a light-activated pump. In this system, upon illumination visible light, photo-induced gradient created by BR shown to be coupled active of substrates through