CAREER: Bioinorganic Redox Chemistry and Protein-Protein Interactions at an Electrode

Trustees Of Boston University, Boston

Investigators

Abstract

Intellectual merit. Microbes such as Nitrosomonas europaea and Shewanella oneidensis are capable of remarkable biochemical transformations as part of their overall metabolism. Like all living things, micro-organisms harness energy by elaborate schemes in which electrons move from one protein molecule to another, forming a kind of internal circuitry. Traditionally, the determination of the composition and circuitry of the inner electrical workings of a cell would be quite difficult. In this research, a new analytical tool, protein film voltammetry, will be used to learn about the fundamental ways N. europaea and S. oneidensis move electrons within the components of their internal circuitry. Specifically, this project will report upon the oxidation/reduction (redox) properties of monoheme and multiheme cytochromes as individual purified proteins and macromolecular complexes. A series of multiheme electron transfer proteins (CymA, MtrA, STC, cyt c554, and cyt cm552) will be studied to understand the potential role redox-cooperativity plays in the function of these proteins. Then, model protein-protein complexes will be prepared and analyzed electrochemically, to determine how protein-protein interactions influence and modulate the thermodynamics and kinetics of biological electron transfer. Ultimately, this project will focus on determination of how protein electrochemistry can be used as a rapid tool for the identification of labile, redox-active protein-protein complexes. Broader impacts. This project will provide important insights into functional, labile protein-protein interactions as well as aid the development of protein electrochemistry as an analytical tool. Understanding the complex electrochemical pathways of N. europaea and S. oneidensis will enable the exploitation of these organisms in the bioenergy sciences. Further, the multi-disciplinary research will proceed alongside an educational plan that will develop (1) a new, first-year chemistry course that provides an interdisciplinary, problem- and research-oriented learning environment; (2) multi-disciplinary graduate courses in bioinorganic chemistry; (3) a seminar series in graduate research conduct and ethics, and (4) a conduit for undergraduate and high-school summer research.