Cell Division in a Filamentous, Sporulating Bacterium

为了在细胞周期的正确时间和正确位置存款隔膜，单细胞细菌必须能够监测DNA复制的完成和新复制的DNA的分离，定位细胞的中心，并启动新的细胞壁和细胞质膜的向心生长。 由于二分裂是最常被研究的细菌繁殖的唯一方式，因此细胞分裂所需的许多基因是必不可少的，因此不能通过突变分析轻易地解剖。 与其他细菌不同，链霉菌生长为分枝、丝状、多核细胞，其经历多次分隔事件以形成孢子链。 链霉菌分化中的关键事件包括形成注定成为孢子的隔室所必需的大量和相对同步的分隔，以及分隔前分化结构的广泛生长。 为了确定结构，酶和调节蛋白负责细胞结构的这一巨大变化，该项目的重点是孢子形成隔膜形成所需的两种蛋白质：FtsZ和隔膜特异性青霉素结合蛋白。 这些实验将通过使用整合的报告系统，突变体分析，和转录所需的蛋白质的ftsZ的分析，确定参与的因素在灰色链霉菌ftsZ的发育调控。 将分离编码灰色链霉菌隔膜特异性青霉素结合蛋白的基因，并确定其核苷酸序列;在另一个实验中，将破坏该基因以确认其在隔膜形成中的作用。 细胞分裂是所有生物体的基本特性。 为了繁殖，每个细胞必须分裂以产生可存活的子细胞。 丝状细菌细胞分裂的分析是一个逻辑系统，用于研究细胞分裂的正确时间和位置的分子事件。 通过表征这些细菌中的细胞分裂机制，这项研究将有助于建立细胞生长的基石。

Kendrick 9724038 To deposit a septum at the correct time in the cell cycle and at the correct location, a unicellular bacterium must be able to monitor the completion of DNA replication and the segregation of the newly replicated DNA, locate the center of the cell, and initiate the centripetal growth of new cell wall and cytoplasmic membrane. Because binary fission is the only means by which most commonly studied bacteria reproduce, many of the genes required for cell division are essential and thus cannot be readily dissected by mutation analysis. Unlike other bacteria, Streptomyces grows as branched, filamentous, multinucleoidal cells that undergo multiple septation events to form chains of spores. Key events in Streptomyces differentiation include the massive and relatively synchronous septation necessary to form the compartments destined to become the spores, and the extensive growth of the differentiated structures prior to septation. To identify structural, enzymatic, and regulatory proteins responsible for this dramatic change in cell structure, this project focuses on two proteins required for sporulation septum formation: FtsZ and the septum-specific penicillin-binding protein. These experiments will identify the factors involved in the developmental regulation of ftsZ in Streptomyces griseus by using an integrative reporter system, mutant analysis, and the analysis of proteins required for transcription of ftsZ. The gene encoding the septum-specific penicillin-binding protein of S.griseus will be isolated and its nucleotide sequence determined; in another experiment this gene will be disrupted to confirm its role in septum formation. Cell division is an essential property of all organisms. To reproduce, each cell must divide to generate viable daughter cells. The analysis of cell division in filamentous bacteria is a logical system to use to study molecular events central to the correct timing and location of cell division. By characterizing the cell division machine ry in these bacteria, this research will help to build the cornerstones of cell growth.