Molecular Topology and Development in a Photosynthetic Membrane System

绿体是附着在绿色光合细菌细胞质膜内表面的光收集结构。绿藻叶绿体的多肽组成由三种主要蛋白质成分和第四种次要多肽组成。这四种蛋白的功能作用已经初步确定。该项目旨在确定这些蛋白质在光合装置发育过程中所起的作用。重组基因技术被用于分离叶绿体的两种主要蛋白质成分的基因。一种叶绿体蛋白（Mr 5700）的基因已经被克隆出来：它包含一个羧基末端延伸的编码区，这个编码区不存在于成熟的蛋白质上，它可能对蛋白质靶向到叶绿体内适当的组装位置很重要。本研究详细讨论了编码叶绿体蛋白的基因的遗传结构、组织和调控。绿色和紫色的光合细菌拥有比高等植物更简单的光合作用类型。在这些细菌中，光被作为能量来源收集，以支持细菌从大气中的二氧化碳中合成糖和其他有机成分，但不产生氧气。由于它们相对简单，这些细菌提供了有用的模型系统，这些模型系统通常比高等植物系统更易于进行详细分析。对细菌的研究对提高光合作用的基础知识作出了重大贡献。富勒博士的研究提供了有关生物化合物和复杂细胞结构的结构和功能的基本信息，这些结构和细胞结构负责绿色细菌有效地收集阳光

Chlorosomes are light-harvesting structures attached to the inner surface of the cytoplasmic membrane in green photosynthetic bacteria. The polypeptide composition of Chloroflexus chlorosomes consists of three major protein components and a fourth minor polypeptide. Functional roles for all four proteins have been tentatively assigned. This project is aimed at determining the role played by these proteins during the development of the photosynthetic apparatus. Recombinant genetic techniques are being used to isolate the genes for two major proteins components of the chlorosome. The gene for one chlorosome protein (Mr 5700) has already been cloned: it contains a coding region for a carboxyl-terminal extension that is not present on the mature protein and which may be important for targetting the protein to the appropriate assembly site within the chlorosome. This investigation deals in detail with the genetic structure, organization and regulation of genes encoding chlorosome proteins. The green and purple photosynthetic bacteria possess a simpler type of photosynthesis than that occurring in higher plants. In these bacteria light is harvested as an energy source to support the synthesis of sugars and other organic components of the bacteria from atmospheric carbon dioxide, but oxygen is not produced. Because of their relative simplicity these bacteria provide useful model systems which are often more amenable to detailed analysis than are higher- plant systems. Studies of bacteria have made major contributions to the advancement of fundamental knowledge of photosynthesis. Dr. Fuller's investigations provide essential information about the structure and function of the biological compounds and complex cellular structures that are responsible for the useful harvesting of sunlight by green bacteria.***//