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Updated: Mar 26, 2026

In vitro Investigation of the MexAB Efflux Pump From Pseudomonas aeruginosa
Published on: February 17, 2014
Proton-coupled electron hopping in Ru-modified P. aeruginosa azurin
Jeffrey J Warren1,2, Oliver S Shafaat3, Jay R Winkler3
1Beckman Institute, California Institute of Technology, Pasadena, CA, 91125, USA. j.warren@sfu.ca.
Abstract:
We constructed two artificial multiple-step electron transfer (hopping) systems based on Pseudomonas aeruginosa azurin where a tyrosine (YOH) is situated between Ru(2,2'-bipyridine)2(imidazole)(histidine) and the native copper site: RuH107YOH109 and RuH124-YOH122. We investigated the rates of Cu(I) oxidation by flash-quench generated Ru(III) over a range of conditions that probed the role of proton-coupled oxidation/reduction of YOH in the reaction. Rates of Cu(I) oxidation were enhanced over single-step electron transfer by factors between 3 and 80, depending on specific scaffold and buffer conditions.
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