GENETIC ANALYSIS OF BACTERIAL PHOTOSYNTHESIS

该项目长期目标是确定并绘制两者 从基因和物理上讲，这些遗传元素和区域是 参与细胞因子的合成、结构/功能和调节 诱导型细胞内膜系统的研究 光异养菌，球形红细菌。这种分子遗传 方法，再加上详细的膜生化分析 结构和功能将有助于更好地理解 膜合成和调控的遗传学基础。重要的是 生物膜对正常细胞活动的最好体现在 这种膜在肿瘤状态下的变化，或 强直性肌强直中改变的膜的性质，或 家族性葡萄糖-半乳糖吸收不良患者的肠道己糖转运 仅举几个例子。作为额外的长期目标，我们建议： 研究：缺氧光合作用的起源，发展 红豆杉线粒体线二倍体状态及其进化 发展。这些长期目标将得到具体解决。 通过分离、鉴定、互补和作图 直接参与细胞内膜合成的基因和 监管，特别强调#年的早期步骤 卟啉环的生物合成以及独特的研究进展 分离新突变体的富集化/筛选条件 膜合成和/或调节缺陷的菌株。因为. 球藻的高含量(70%) 需要注意的是这些基因的表达 元素以及遗传或假遗传系统的发展 这将有助于对这些复杂过程的详细分析。 此外，球藻中存在两条不同的染色体。 对于许多遗传座位来说，代表了一种亚二倍体状态， 提供了一个独一无二的机会来研究 在这个非常原始的实验系统中独立的连锁群。在……里面 具体地说，维护每个环节的物理结构 群体及其遗传稳定性和各连锁群的互作 在基因表达的水平上，我们应该进一步理解 更复杂系统的起源。我们有能力雇佣一名相对 简单的遗传系统作为工具更好地理解更复杂的 同源和非同源染色体之间的相互作用 可以更全面地理解真核生物中的二倍体状态 系统。

The long-tern objectives for this project are to identify, and map both genetically and physically, those genetic elements and regions which are involved in the synthesis, structure/function, and regulation of the inducible intracellular membrane system in teh faculative photoheterotroph, Rhodobacter sphaeroids. This molecular genetic approach, coupled with a detailed biochemical analysis of membrane structure and function will lead to a better understanding of the genetic basis for membrane synthesis and regulation. The importance of biological membranes to normal cellular activities is best reflected in the alterations of such membranes in the neoplastic state, or the properties of altered membranes in myotonia, or the alteration in intestinal hexose transport in familial glucose-galactose malabsorption, to mention a few. As additional long-term objectives, we propose to examine: the origins of anoxygenic photosynthesis, the development of the diploid state and the evolution of the mitochondrial line of development. These long-term objectives will be specifically addressed through the isolation, identification, complementation and mapping of genes directly involved in intracellular membrane synthesis and regulation with special emphasis directed towards the early steps in porphyrin ring biosynthesis as well as the development of unique enrichment/selection conditions for the isolation of novel mutant strains defective in membrane synthesis and/or regulation. Because of high quanine plus cytosine content (70%) of R. sphaeroides particular attention needs to be directed to the expression of these genetic elements as well as the development of genetic or pseudogenetic systems which will facilitate a detailed analysis of these complex processes. In addition, the presence of two distinct chromosomes in R. sphaeroides representing for a number of genetic loci, a merodiploid state, represents a unique opportunity to investigate the interaction between separate linkage groups in this very primitive experimental system. In particular, the maintenance of the physical structure of each linkage group, its genetic stability and the interaction of each linkage group at the level of gene expression shoul further our understanding of the origins of more complex systems. Our ability to employ a relatively simple genetic system as a tool to better understand the more complex interactions between homologous as well as non-homologous chromosomes can lead to a fuller understanding of the diploid state in eukaryotic systems.