Electron-transfer (ET) reactions play a key role in many biological processes. In these systems the donor and acceptor sites can be separated by distances of 10-25 angstrom unit.
Our aim i s to probe the factors that control the rates of long-range ET: site- to-site distance, driving force, nature of the intervening protein medium and of the redox centers, and reorganization energy. We intend to study and to compare intramolecular long-range ET reactions in ruthenium (II/III) derivatives of structurally well- characterized iron and copper proteins: bovine cytochrome b5, Alcaligenes denitrificans azurin, and high-potential iron-sulfur proteins from Chromatium vinosum, Thiocapsa roseopersicina, and Chromatium gracile. We also intend to study mutants of rat cytochrome b5 with modifications designed to address medium and distance effects systematically. During the next three years, we propose: (1) to prepare highly purified samples of the above wild-type and mutant proteins labeled at selected surface histidine residues with ruthenium (II/III) reagents; (2) to characterize these modified proteins by spectroscopic and electrochemical measurements; (3) to determine by flash photolysis experiments the rates of ET between the protein redox center (iron-heme or other metal phorphyrin, blue copper, or iron-sulfur cluster) and the surface- bound ruthenium; and (4) to analyze the electronic (distance, medium) and energetic (driving force, reorganization energy, temperature) components of the long-range ET rates in these prototypal heme, blue cooper, and iron sulfur proteins. The proposed experiments will allow us to develop a better understanding of a fundamental process essential to all living organisms.
| Kozak, John J; Gray, Harry B; Garza-López, Roberto A (2018) Relaxation of structural constraints during Amicyanin unfolding. J Inorg Biochem 179:135-145 |
| Kretchmer, Joshua S; Boekelheide, Nicholas; Warren, Jeffrey J et al. (2018) Fluctuating hydrogen-bond networks govern anomalous electron transfer kinetics in a blue copper protein. Proc Natl Acad Sci U S A 115:6129-6134 |
| Teo, Ruijie D; Hwang, Jae Youn; Termini, John et al. (2017) Fighting Cancer with Corroles. Chem Rev 117:2711-2729 |
| Ener, Maraia E; Gray, Harry B; Winkler, Jay R (2017) Hole Hopping through Tryptophan in Cytochrome P450. Biochemistry 56:3531-3538 |
| Messina, Marco S; Axtell, Jonathan C; Wang, Yiqun et al. (2016) Visible-Light-Induced Olefin Activation Using 3D Aromatic Boron-Rich Cluster Photooxidants. J Am Chem Soc 138:6952-5 |
| Pribisko, Melanie; Palmer, Joshua; Grubbs, Robert H et al. (2016) Cellular uptake and anticancer activity of carboxylated gallium corroles. Proc Natl Acad Sci U S A 113:E2258-66 |
| Teo, Ruijie D; Termini, John; Gray, Harry B (2016) Lanthanides: Applications in Cancer Diagnosis and Therapy. J Med Chem 59:6012-24 |
| Kozak, John J; Gray, Harry B; Garza-López, Roberto A (2016) Structural Stability of Intelectin-1. J Phys Chem B 120:11888-11896 |
| Warren, Jeffrey J; Shafaat, Oliver S; Winkler, Jay R et al. (2016) Proton-coupled electron hopping in Ru-modified P. aeruginosa azurin. J Biol Inorg Chem 21:113-9 |
| Kozak, John J; Gray, Harry B; Garza-López, Roberto A (2016) Cytochrome unfolding pathways from computational analysis of crystal structures. J Inorg Biochem 155:44-55 |
Showing the most recent 10 out of 99 publications
