Dr. David Vinyard from the department of biological sciences at Louisiana State University will speak on the above topic.
In plants, algae, and cyanobacteria, Photosystem II (PSII) uses visible light to strip electrons from water to form O2. The active site of water oxidation is the oxygen-evolving complex (OEC), a Mn4CaO5 inorganic cluster ligated by amino acid residues, oxides, and waters. While the OEC is the source of virtually all O2 on Earth, its biosynthesis pathway, the identity of the substrate water molecules and the chemical mechanism of O-O bond formation are not well established. We use a wide variety of techniques to study these processes including instrument design, molecular biology, protein biochemistry, chemical kinetics and electron paramagnetic resonance spectroscopy. In this talk, Dr. Vinyard will introduce structural models for substrate water binding during the OEC catalytic cycle and will discuss current efforts to regulate the efficiency of photosynthesis by modifying PSII.