Dr. William H. Armstrong, Chemistry Department, Boston College, is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program of the Chemistry Division for a study of biomimetic chemistry relevant to Photosystem II. The overall objective is to gain a sharper understanding of water oxidation that is catalyzed by Photosystem II, whose active site contains an oxygen-bridged manganese cluster. Replicas of the tetramanganese site in Photosystem II will be prepared. Their behavior under redox and pH changes will be investigated to learn how the enzyme cluster may respond to changes experienced during the catalytic cycle. Hypotheses regarding the mechanism of O-O bond formation and release of dioxygen will be evaluated using the model compounds. Emphasis will be placed on investigating the roles played by chloride and calcium cofactors.
Photosynthesis harnesses sunlight energy to drive the production of atmospheric oxygen and the conversion of carbon dioxide into organic material. The focus of this research is to gain a greater understanding of how Photosystem 2 oxidizes water to oxygen. This knowledge may aid the effort to make artificial photosynthetic cells that efficiently split water to produce oxygen and hydrogen gas. Such an advance would facilitate the conversion of our energy economy to hydrogen. Graduate, undergraduate, and postdoctoral students will gain training on this project. In addition, high school students will be given the opportunity to participate in the project.