Biochemistry Seminar: K. V. Lakshmi
Wed, Apr 09
12:00 PM — 1:00 PM
MarshakCity College of New York160 Convent Ave
Marshak, Marshak, MR 1027
K.V. Lakshmi, Rensselaer Poly. Inst.K.V. Lakshmi, Assoc Prof., Dept of Chemistry & Chemical Biology, and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Poly. Inst., will give a talk on "The Mechanism of Solar Water Oxidation: The Role of Proton-coupled Electron Transfer Reactions in Photosystem II"
The solar water-splitting protein complex, photosystem II (PSII), catalyzes one of the most energetically demanding reactions in Nature by using light energy to drive water oxidation. The four-electron water oxidation reaction occurs at the tetranuclear manganese-calcium-oxo (Mn4Ca-oxo) cluster that is present in the oxygen-evolving complex of PSII. Proton-coupled electron transfer (PCET) reactions, which are exquisitely tuned by smart protein matrix effects, are central to the water-oxidation chemistry of PSII. However, the details of PCET processes are not yet understood because of the inability of conventional methods to probe these processes. A major challenge is to develop methods to directly investigate the mechanism of PCET reactions. We will describe ongoing efforts in our laboratory to understand the tuning and regulation of the PCET reactions of PSII. We are developing two-dimensional (2D) hyperfine sublevel correlation spectroscopy methods that provide direct ‘snapshots’ of the photochemical intermediates of the Mn4Ca-oxo, tyrosine and quinone cofactors of PSII.