MECHANISMS OF ESCHERICHIA COLI CHROMOSOMAL REPLICATION

大肠埃希氏菌染色体复制的启动是一个关键事件 细菌的生长周期。这项建议的长期目标 研究是为了获得对DNA启动的生物化学理解 复制及其与细胞生长的协调。DNAA蛋白发挥着重要作用 在启动过程中起着核心作用，似乎决定了 细菌开始复制时的细胞周期。这 蛋白质似乎也在多次复制时同步这一过程 起源于快速生长的细胞，并调节其自身的表达 基因和大肠杆菌的其他几个基因。进一步发展的一种方法 通过生产了解Dna蛋白在大肠杆菌中的作用 DNAA蛋白突变型与野生型的比较分析 键入COMPAREMENT。第二个涉及突变形式的相互作用。 DNAA蛋白和DNAK、GRPE和DNAJ热休克蛋白，它们似乎 影响复制活动，并可能代表一种调控机制 在启动过程中。第三种方法涉及关联 DNAA蛋白结构域对其不同活性的影响 单抗和定点突变。 虽然这项研究解决了一个基本的生化问题，但这样的发现可能 有助于理解染色体复制的机制及其 对高等生物体的管理。这些发现可能在设计中有用 促进或干扰植物细胞生长的试剂，以及 动物。

Initiation of Escherichia coli chromosomal replication is a key event in the bacterial growth cycle. The long term objectives of this proposed research are to obtain a biochemical understanding of the initiation of DNA replication and its coordination to cell growth. dnaA protein plays a central role in the initiation process and appears to determine the time in the bacterial cell cycle when initiation of replication occurs. This protein also appears to synchronize this process at multiple replication origins in a rapidly growing cell, and regulates the expression of its own gene and of several other genes of e. coli. One approach to further understanding of the role of dnaA protein in E coli is by the production and analysis of mutant forms of dnaA protein in comparison with its wild type counterpart. The second involves the interaction of mutant forms of dnaA protein with dnaK, grpE, and dnaJ heat shock proteins which appear to influence replication activity and may represent a mechanism for regulation of the initiation process. The third approach involves correlation of structural domains of dnaA protein to its various activities by use of monoclonal antibodies and by site-specific mutagenesis. While this research addresses a basic biochemical problem such findings may be useful in understanding the mechanism of chromosomal replication and its regulation in higher organisms. These findings may be useful in the design of agents which promote or interfere with cell growth in plants and animals.