title: The influence of the structure of the Au(110) surface on the ordering of a monolayer of cytochrome P450 reductase at the Au(110)/phosphate buffer interface.
abstract: The reflection anisotropy spectra (RAS) observed initially from Au(110)/phosphate buffer interfaces at applied potentials of -0.652 and 0.056 V are very similar to the spectra observed from ordered Au(110) (1 × 3) and anion induced (1 × 1) surface structures respectively. These RAS profiles transform to a common profile after cycling the potential between these two values over 72 h indicating the formation of a less ordered surface. The RAS of a monolayer of a P499C variant of the human flavoprotein cytochrome P450 reductase adsorbed at 0.056 V at an ordered Au(110)/phosphate buffer interface is shown to arise from an ordered layer in which the optical dipole transitions are in a plane that is orientated roughly normal to the surface and parallel to either the [11̄0] or [001] axes of the Au(110) surface. The same result was found previously for adsorption of P499C on an ordered interface at -0.652 V. The adsorption of P499C at the disordered surface does not result in the formation of an ordered monolayer confirming that the molecular ordering is strongly influenced by both the local structure and the long range macroscopic order of the Au(110) surface.
authors.affiliation: Oliver Lodge Laboratory, Department of Physics, University of Liverpool, Liverpool L69 7ZE, UK.
authors.forename: C I
authors.initials: CI
authors.lastname: Smith
authors.affiliation: Oliver Lodge Laboratory, Department of Physics, University of Liverpool, Liverpool L69 7ZE, UK.
authors.forename: J H
authors.initials: JH
authors.lastname: Convery
authors.affiliation: Faculty of Life Sciences, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
authors.forename: B
authors.initials: B
authors.lastname: Khara
authors.affiliation: Faculty of Life Sciences, Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
authors.forename: N S
authors.initials: NS
authors.lastname: Scrutton
authors.affiliation: Oliver Lodge Laboratory, Department of Physics, University of Liverpool, Liverpool L69 7ZE, UK.
authors.forename: P
authors.initials: P
authors.lastname: Weightman
keywords: adsorption; cytochrome P450 reductase; gold; reflection anisotropy spectroscopy