title: Conductive wiring of immobilized photosynthetic reaction center to electrode by cytochrome C.
abstract: The photosynthetic reaction center (RC) found in photosynthetic bacteria is one of the most advanced photoelectronic devices developed by nature. However, after immobilization on the electrode surface, the efficiency of electron transfer (ET) between the RC and the electrode is relatively low. This inefficiency has limited the possibility of using the RC for technological applications. Here we show that photoinduced electron transfer between the immobilized RC and a gold electrode can be increased by several tens-fold by incorporation of cytochrome c into the RC-self-assembled monolayer (SAM)-electrode complex. The effect does not depend on the initial redox state of the cytochrome and seems to be the result of the formation of a complex between the RC and the cytochrome c serving as an ET wire. This observation opens the possibility for electrochemical analysis of the special pair in the RC protein that is deeply buried inside the protein globe and is barely electrically addressable from the electrode surface.
authors.affiliation: Center for Bio/Molecular Sciences & Engineering, U.S. Naval Research Laboratory, Washington, D.C. 20375, USA. nlebedev@cbmse.nrl.navy.mil
authors.forename: Nikolai
authors.initials: N
authors.lastname: Lebedev
authors.forename: Scott A
authors.initials: SA
authors.lastname: Trammell
authors.forename: Anthony
authors.initials: A
authors.lastname: Spano
authors.forename: Evgeny
authors.initials: E
authors.lastname: Lukashev
authors.forename: Igor
authors.initials: I
authors.lastname: Griva
authors.forename: Joel
authors.initials: J
authors.lastname: Schnur
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D045304:Cytochromes c / Q000737:chemistry*; D004583:Electrons; D004800:Enzymes, Immobilized / Q000737:chemistry; D008958:Models, Molecular; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D045322:Photosynthetic Reaction Center Complex Proteins; D045304:Cytochromes c