title: Light-driven electron injection from a biotinylated triarylamine donor to [Ru(diimine)3](2+)-labeled streptavidin.
abstract: Electron transfer from a biotinylated electron donor to photochemically generated Ru(iii) complexes covalently anchored to streptavidin is demonstrated by means of time-resolved laser spectroscopy. Through site-selective mutagenesis, a single cysteine residue was engineered at four different positions on streptavidin, and a Ru(ii) tris-diimine complex was then bioconjugated to the exposed cysteines. A biotinylated triarylamine electron donor was added to the Ru(ii)-modified streptavidins to afford dyads localized within a streptavidin host. The resulting systems were subjected to electron transfer studies. In some of the explored mutants, the phototriggered electron transfer between triarylamine and Ru(iii) is complete within 10 ns, thus highlighting the potential of such artificial metalloenzymes to perform photoredox catalysis.
authors.affiliation: Department of Chemistry, University of Basel, Spitalstrasse 51, CH-4056 Basel, Switzerland. thomas.ward@unibas.ch.
authors.forename: Sascha G
authors.initials: SG
authors.lastname: Keller
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland. oliver.wenger@unibas.ch.
authors.forename: Andrea
authors.initials: A
authors.lastname: Pannwitz
authors.affiliation: Department of Chemistry, University of Basel, Spitalstrasse 51, CH-4056 Basel, Switzerland. thomas.ward@unibas.ch.
authors.forename: Fabian
authors.initials: F
authors.lastname: Schwizer
authors.affiliation: Department of Chemistry, University of Basel, Spitalstrasse 51, CH-4056 Basel, Switzerland. thomas.ward@unibas.ch.
authors.forename: Juliane
authors.initials: J
authors.lastname: Klehr
authors.affiliation: Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland. oliver.wenger@unibas.ch.
authors.forename: Oliver S
authors.initials: OS
authors.lastname: Wenger
authors.affiliation: Department of Chemistry, University of Basel, Spitalstrasse 51, CH-4056 Basel, Switzerland. thomas.ward@unibas.ch.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Ward
mesh_terms: D019921:Biotinylation / Q000379:methods*; D056831:Coordination Complexes / Q000737:chemistry*; D004579:Electron Transport; D007700:Kinetics; D008027:Light; D015394:Molecular Structure; D010084:Oxidation-Reduction; D012428:Ruthenium / Q000737:chemistry*; D019809:Streptavidin / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D012428:Ruthenium; D019809:Streptavidin