title: Electrochemical Field-Effect Transistor Utilization to Study the Coupling Success Rate of Photosynthetic Protein Complexes to Cytochrome c.
abstract: Due to the high internal quantum efficiency, reaction center (RC) proteins from photosynthetic organisms have been studied in various bio-photoelectrochemical devices for solar energy harvesting. In vivo, RC and cytochromec(cytc; a component of the biological electron transport chain) can form a cocomplex via interprotein docking. This mechanism can be used in vitro for efficient electron transfer from an electrode to the RC in a bio-photoelectrochemical device. Hence, the success rate in coupling RCs to cytcis of great importance for practical applications in the future. In this work, we use an electrochemical transistor to study the binding of the RC to cytochrome. The shift in the transistor threshold voltage was measured in the dark and under illumination to estimate the density of cytochrome and coupled RCs on the gate of the transistor. The results show that ~33% of the cytcs on the transistor gate were able to effectively couple with RCs. Due to the high sensitivity of the transistor, the approach can be used to make photosensors for detecting low light intensities.
authors.affiliation: Department of Electrical Engineering, University of South Florida (USF), Tampa, FL 33620, USA. atakshi@usf.edu.
authors.forename: Arash
authors.initials: A
authors.lastname: Takshi
authors.affiliation: Department of Chemistry, University of California Irvine, Irvine, CA 92697, USA. hyaghoub@uci.edu.
authors.forename: Houman
authors.initials: H
authors.lastname: Yaghoubi
authors.affiliation: Department of Electrical Engineering, University of South Florida (USF), Tampa, FL 33620, USA. jingw@usf.edu.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Microbiology and Immunology, University of British Columbia (UBC), Vancouver, BC V6T1Z3, Canada. djun89@gmail.com.
authors.forename: Daniel
authors.initials: D
authors.lastname: Jun
authors.affiliation: Department of Microbiology and Immunology, University of British Columbia (UBC), Vancouver, BC V6T1Z3, Canada. j.beatty@ubc.ca.
authors.forename: J Thomas
authors.initials: JT
authors.lastname: Beatty
mesh_terms: D045304:Cytochromes c / Q000737:chemistry / Q000378:metabolism*; D055664:Electrochemical Techniques; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D014173:Transistors, Electronic
chemical_list: D045322:Photosynthetic Reaction Center Complex Proteins; D045304:Cytochromes c
keywords: bio-photosensor; charge density; protein-protein interaction; reaction center; rhodobacter sphaeroides