U.S.-Japan Cooperative Research: Analysis of the Photosystem I Reaction Center by Resolution-Reconstitution Methods

该奖项将促进波特兰州立大学化学系John H. Golbeck教授；池上勇教授，东京大学，相模子，日本；和日本冈崎国立基础生物学研究所Shigeru Itoh教授。科学家们正在合作研究绿色植物和蓝藻发生光合作用时发生的一些基本过程。他们重点研究了两个光化学系统中依次参与整个光合过程的低电位系统（光系统I）。这个合作项目是基于美国和日本研究人员的综合个人能力，有选择地去除叶绿素分子、叶绿醌分子和组成反应中心的铁硫簇，然后再放回原处。这种新开发的选择性分辨率和重建方案，结合科学家影响多肽-蛋白质再结合的能力，为解决关于光系统i中电子流途径的长期问题提供了新的机会。通过在重建复合体时留下一些成分，这些亚基的功能可能会更好地被理解。为了合成人工中心或修饰中心，在络合物重组之前，一些组分也可以进行化学改变或交换，并确定其效果。此外，某些铁和硫同位素的使用将允许进行各种光谱研究，产生有关该复合物的结构信息。

This award will facilitate continued cooperation between Professor John H. Golbeck, Department of Chemistry, Portland State University; Professor Isamu Ikegami, Teikyo University, Sagamiko, Japan; and Professor Shigeru Itoh, National Institute of Basic Biology, Okazaki, Japan. The scientists are collaborating in a study of some of the basic processes occurring when photosynthesis takes place in green plants and cyanobacteria. They are focusing on the lower- potential system (Photosystem I) of two photochemical systems involved sequentially in the overall photosynthetic process. This cooperative project is based on the combined individual abilities of the U.S. and Japanese researchers to remove and then put back, selectively, the chlorophyll molecules, the phylloquinone molecules, and the iron-sulfur clusters that make up the reaction center. This newly developed, selective resolution and reconstitution protocol, combined with the scientists' ability to effect polypeptide - protein rebinding, offers new opportunities to address longstanding questions regarding the pathways of electron flow in Photosystem I. By leaving some of the components out when reconstructing the complex, the function of these subunits may become better understood. Some of the components may also be chemically altered or exchanged before the complex is reconstituted, in order to synthesize artificial or modified centers, and the effect determined. In addition, use of certain iron and sulfur isotopes will permit various spectroscopic studies to be carried out, yielding structural information regarding the complex.