title: Enhanced photocurrent in engineered bacteriorhodopsin monolayer.
abstract: The integration of the transmembrane protein bacteriorhodopsin (BR) with man-made electrode surfaces has attracted a great deal of interest for some two decades or more and holds significant promise from the perspective of derived photoresponse or energy capture interfaces. Here we demonstrate that a novel and strategically engineered cysteine site (M163C) can be used to intimately and effectively couple delipidated BR to supporting metallic electrode surfaces. By virtue of the combined effects of the greater surface molecular density afforded by delipidation, and the vicinity of the electrostatic changes associated with proton pumping to the transducing metallic continuum, the resulting films generate a considerably greater photocurrent density on wavelength-selective illumination than previously achievable with monolayers of BR. Given the uniquely photoresponsive, wavelength-selective, and photostable characteristics of this protein, the work has implications for utilization in solar energy capture and photodetector devices.
authors.affiliation: Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, UK.
authors.forename: Amol V
authors.initials: AV
authors.lastname: Patil
authors.forename: Thenhuan
authors.initials: T
authors.lastname: Premaruban
authors.forename: Olivia
authors.initials: O
authors.lastname: Berthoumieu
authors.forename: Anthony
authors.initials: A
authors.lastname: Watts
authors.forename: Jason J
authors.initials: JJ
authors.lastname: Davis
mesh_terms: D019943:Amino Acid Substitution; D001436:Bacteriorhodopsins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D003545:Cysteine / Q000737:chemistry; D004566:Electrodes; D018625:Microscopy, Atomic Force; D009154:Mutation; D017785:Photons; D012993:Solar Energy; D055672:Static Electricity
chemical_list: D001436:Bacteriorhodopsins; D003545:Cysteine