Spectroscopic and Structural Studies of Primary Photochemical Processes in Photosynthesis

被称为光系统I的光化学反应中心复合体的特征是存在作为电子受体的结合的铁-硫中心。具有光化学活性的天然光系统I复合体的制备至少包含12个亚基，其中大多数没有成熟的功能。本项目的总体目标是确定这些亚单位的功能并确定它们的结构组织。主要的实验技术将是生化分解和重建技术，这些方法将辅之以生物物理测量，以监测许多电子载体的功能状态。除了表征这个复合体，该项目还将考虑从厌氧光合细菌(称为绿色硫磺细菌)中分离出来的反应中心复合体中多肽亚单位的结构组织，因为有令人信服的生物物理证据表明，该复合体具有与植物型光系统I复合体相似的功能成分。该项目的结果将有助于确定光化学反应中心复合体中光诱导电子转移的机制，并将提供关于光合作用反应中心复合体从原始系统向更高级系统演化的信息。

The photochemical reaction center complex known as Photosystem I is characterized by the presence of bound iron-sulfur centers that function as electron acceptors. Preparations of the photochemically active native Photosystem I complex contains at least one dozen subunits, most of which have no well established function. The overall objective of this project is to define the function of these subunits and to determine their structural organization. The major experimental techniques will be those of biochemical resolution and reconstitution and these methods will be supplemented with biophysical measurements to monitor the functional state of many of the electron carriers. In addition to characterizing this complex, the project will also consider the structural organization of polypeptide subunits in a reaction center complex isolated from anaerobic photosynthetic bacteria known as green sulfur bacteria since there is compelling biophysical evidence that indicates this complex has functional components that are similar to those in the plant-type Photosystem I complex. Results from this project will aid in defining the mechanism of photoinduced electron transfer in a photochemical reaction center complex and will provide information on the evolution of the photosynthetic reaction center complex from primitive to more advanced systems.