Bacterial Reaction Centers With New Photochemical Properties

有了这个奖项，化学系的生命过程化学项目和分子与细胞生物科学系的分子生物物理学集群共同资助亚利桑那州立大学的James艾伦教授和JoAnn威廉姆斯博士研究光合生物将光转化为化学能的能力的因素。 该项目的总体目标是设计新型金属簇，可以催化光诱导氧化反应。 在他们的实验室和他们的合作者的实验室中，可以使用各种实验技术来探测新型金属簇的活性。 这些研究旨在深入了解金属簇合物进行复杂多电子反应所需的要求，包括从水中生产分子氧。 艾伦教授和威廉姆斯博士的研究使用蛋白质设计来回答有关光合反应的基本科学问题，并包括科学研究的多样化参与，包括本科生接触化学/生物学界面现代研究的重要元素。在所有光合系统中，主要的能量转换事件是色素-蛋白质复合物中电荷分离态的光诱导产生。详细的光谱研究和这些复合物的三维结构为理解它们的许多功能奠定了坚实的基础。然而，锰簇光系统II催化水氧化的基本生物过程的机制是该领域的一个主要悬而未决的问题。因此，该项目旨在剖析这种能力。细菌反应中心将作为一个平台，在一个明确的蛋白质环境中重建光系统II锰簇的特征。各种锰簇合物的关键性质的表征将揭示促进氧化反应的金属簇合物中的共同图案。总的来说，从这些研究中获得的见解应该有助于建立分子概念，解释蛋白质中的锰辅因子如何有效地进行复杂的化学反应，并导致能够实现有益的光导向催化过程的新型生物系统的发展。

With this award, the Chemistry of Life Processes Program in the Division of Chemistry and the Molecular Biophysics Cluster in the Division of Molecular and Cellular Biosciences are jointly funding Professor James Allen and Dr. JoAnn Williams of Arizona State University to investigate the factors that give photosynthetic organisms the ability to convert light into chemical energy. The overall objective of this project is to engineer novel metal clusters that can catalyze light-induced oxidation reactions. A variety of experimental techniques are available in their laboratory and those of their collaborators to probe the activity of the novel metal clusters. The studies are directed at providing insight into the requirements needed for metal clusters to perform complex multi-electron reactions, including the production of molecular oxygen from water. The research of Professor Allen and Dr. Williams in using protein design to answer fundamental scientific questions about photosynthetic reactions and includes diverse participation in scientific research, including an important element of undergraduate exposure to modern research at the chemistry/biology interface.In all photosynthetic systems, the primary energy transduction event is the light-induced generation of a charge-separated state in a pigment-protein complex. Detailed spectroscopic studies and three-dimensional structures of these complexes form a firm foundation for understanding many of their functions. However, the mechanism by which the manganese cluster of photosystem II catalyzes the essential biological process of water oxidation is a major outstanding question in the field. Thus this project is directed towards dissecting this capacity. The bacterial reaction center will serve as a platform to recreate features of the manganese cluster of photosystem II in a well-defined protein environment. Characterization of key properties of a variety of manganese clusters would reveal common motifs in metal clusters that facilitate oxidation reactions. Overall, the insight gained from these studies should help establish molecular concepts that explain how manganese cofactors in proteins efficiently perform intricate chemical reactions, as well as lead to the development of novel biological systems that are capable of accomplishing beneficial light-directed catalytic processes.