Spectroscopic and Structural Studies of Primary Photochemical Processes in Photochemical Processes in Photosynthesis

光化学反应中心是光合膜中吸收的光能转化为化学能的部位。虽然最近的生物化学证据支持光系统II和细菌反应中心之间的结构相似性，但光系统I （PSI）反应中心复合物的成分仍然不明确。只是在过去的几年里，已经有了很好的表征的高等植物PSI制剂，这些制剂保留了体内PSI的结构和功能方面。氧进化生物的PSI反应中心配合物是当前项目的重点，由于它含有低电位电子受体系统，因此已知其功能与其他配合物不同，但其特征较少。Malkin博士将研究分离PSI复合体中多肽亚基的性质以及特定电子转移载体与特定亚基的关联。还将定义复合体内单个亚基的化学计量学以及这些亚基在响应环境信号时含量的变化。

The photochemical reaction center is the site in the photosynthetic membrane where absorbed light energy is converted into chemical energy. While recent biochemical evidence has supported the structural similarity between photosystem II and the bacterial reaction center, components in the photosystem I (PSI) reaction center complex remain more poorly defined. It is only in the past several years that well-characterized higher plant PSI preparations which retain the structural and functional aspects of PSI in vivo have been available. The PSI reaction center complex of oxygen-evolving organisms, which is the focal point of the current project, is less well characterized although it is known to be functionally different than the other complexes since it contains a low potential electron acceptor system. Dr. Malkin will examine the nature of the polypeptide subunits in the isolated PSI complex and the association of specific electron transfer carriers with specific subunits. The stoichiometry of the individual subunits within the complex and changes in the content of these subunits in response to environmental signal will also be defined.