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物的特征是存在作为电子受体的结合铁硫中心。 具有光化学活性的天然光系统 I 复合物的制剂包含至少十几个亚基，其中大多数没有明确的功能。 该项目的总体目标是定义这些子单元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辨率和重构技术，这些方法将辅以生物物理测量，以监测许多电子载体的功能状态。 除了表征该复合物外，该项目还将考虑从厌氧光合细菌（称为绿硫细菌）分离的反应中心复合物中多肽亚基的结构组织，因为有令人信服的生物物理证据表明该复合物具有与植物型光系统 I 复合物相似的功能成分。 该项目的结果将有助于定义光化学反应中心复合体中光诱导电子转移的机制，并将提供有关光合反应中心复合体从原始系统到更先进系统演化的信息。

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.