Natural photosynthetic energy research is aimed at resolving fundamental mechanisms of photochemical energy conversion in photosynthetic proteins. For over 50 years, our group has conducted fundamental photosynthetic reaction center (RC) studies that helped determine the primary reactions and structures of these proteins. RCs are highly evolved, finely tuned protein-pigment complexes optimized for solar energy conversion. The primary reaction in RC proteins involves light-induced rapid, sequential electron transfer that results in stable charge separation and the consequent electrochemical potential is converted to useful chemical energy by selective coupling to secondary reaction sequences. Thus, both the charge separation process and the chemical events that immediately follow are important features of solar energy conversion. A distinction of our program is the close interaction and feedback loops between advanced bioinorganic chemistry, EPR spectroscopy, synchrotron-based X-ray methods, and EM imaging to investigate key energy and electron transfer reactions in natural photosynthesis to define Nature’s mechanistic control of solar energy in dynamic, specifically tailored RC protein matrices coupled to multi-scale photosynthetic electron flow and function.
O. G. Poluektov, J. Niklas, L. M. Utschig. Spin-correlated radical pairs as quantum sensors of bidirectional electron transfer mechanisms in Photosystem I. J. Phys. Chem. B, 2019, 123, 7536-7544. link
J. Ho, E. Kish, D. D. Mendez-Hernandez, K. Wong, S. Pillai, G. Kodis, J. Nikas, O. G. Poluektov, D. Gust, T. A. Moore, A. L. Moore, V. S. Batista, B. Robert.
Triplet-triplet energy transfer in artificial and natural photosynthetic antennas. Proc. Natl. Acad. Sci. 2017, 114, E5513-E5521. link
O. G. Poluektov, L. M. Utschig. Directionality of electron transfer in Type I reaction center proteins: High-frequency EPR study of PSI with removed iron-sulfur centers. J. Phys. Chem. B, 2015, 119, 13771-13776. link
J. D. Megiatto, D. D. Méndez-Hernández, M. E. Tejeda-Ferrari, A.-L. Teillout, O. G. Poluektov, T. Rajh, V. Mujica, T. L. Groy, D. Gust, T. A. Moore, A. L. Moore. A bioinspired construct that mimics radical interactions of the Tyr-His pairs of photosystem II. Nature Chem., 2014, 6, 423-428. link
L. Huang, N. Ponomarenko, G. P. Wiederrecht, D. M. Tiede. Cofactor-specific photochemical function resolved by ultrafast spectroscopy in photosynthetic reaction center crystals. Proc. Natl. Acad. Sci, 2012, 109, 4851-4856. link
L. M. Utschig, D. M. Tiede, O. G. Poluektov. Light-induced alteration of low temperature interprotein electron transfer between Photosystem I and flavodoxin. Biochemistry, 2010, 49, 9682-9684. link
Contact Lisa Utschig for more information.