Description of Research:Combines experimental and theoretical research to study how proteins control the rates and equilibria of electron and proton transfer reactions. Acidic and basic amino-acid side chains control a protein's charge by binding or releasing protons. Some proteins bind cofactors that accept or donate electrons. A protein's charge helps determine its folding pattern, the binding of substrates, and the efficiency of enzyme catalysis. In addition, the motions of protons and electrons across proteins embedded in cellular membranes create electrochemical gradients that store energy.
Professor Gunner's experimental studies use time-resolved optical spectroscopy to monitor electron-transfer reactions. The research focuses on photosynthesis, where light energy starts a series of electron tunneling and proton binding reactions. Studies probe the ability of photosynthetic proteins to store the energy of light with very high efficiency. Computer calculations use the Poisson-Boltzmann equation to test how the protein's structure can modify the free energy of charges in different locations. In addition, quantum-mechanical tunneling theories are used to try to understand electron-transfer rates under different conditions. Additional biophysical and biomedical research is conducted by some of our condensed matter physicists and by workers at the Mediphotonics Laboratory of the Institute for Ultrafast Spectroscopy and Lasers. Check her personal page.
