title: Monitoring interfacial bioelectrochemistry using a FRET switch.
abstract: Generation of functionally active biomolecular monolayers is important in both analytical science and biophysical analyses. Our ability to monitor the redox-active state of immobilized proteins or enzymes at a molecular level, from which stochastic and surface-induced variations would be apparent, is impeded by comparatively slow electron-transfer kinetics and associated signal:noise difficulties. We demonstrate herein that by covalently tethering an appropriate dye to the copper protein azurin a highly oxidation-state-sensitive FRET process can be established which enables redox switching to be optically monitored at protein levels down to the zeptomolar limit. The surface-potential-induced cycling of emission enables the redox potential of clusters of a few hundred molecules to be determined.
authors.affiliation: Central Research Laboratory, Mansfield Road, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom.
authors.forename: J J
authors.initials: JJ
authors.lastname: Davis
authors.forename: H
authors.initials: H
authors.lastname: Burgess
authors.forename: G
authors.initials: G
authors.lastname: Zauner
authors.forename: S
authors.initials: S
authors.lastname: Kuznetsova
authors.forename: J
authors.initials: J
authors.lastname: Salverda
authors.forename: T
authors.initials: T
authors.lastname: Aartsma
authors.forename: G W
authors.initials: GW
authors.lastname: Canters
mesh_terms: D001400:Azurin / Q000737:chemistry*; D001703:Biophysics / Q000379:methods*; D002627:Chemistry, Physical / Q000379:methods*; D004396:Coloring Agents / Q000494:pharmacology; D003300:Copper / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D004583:Electrons; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D007700:Kinetics; D008956:Models, Chemical; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D017434:Protein Structure, Tertiary; D013499:Surface Properties
chemical_list: D004396:Coloring Agents; D001400:Azurin; D003300:Copper