Cell Division in a Filamentous, Sporulating Bacterium

肯德里克9724038要在细胞周期的正确时间和正确的位置沉积隔膜，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膜的向心生长。由于二元分裂是最常被研究的细菌繁殖的唯一方式，许多细胞分裂所需的基因是必不可少的，因此不容易通过突变分析来剖析。与其他细菌不同，链霉菌生长为分枝的丝状多核细胞，经历多次分离事件形成孢子链。链霉菌分化的关键事件包括大量和相对同步的隔膜，以形成注定成为孢子的隔室，以及在隔膜之前分化结构的广泛生长。为了确定导致细胞结构这种戏剧性变化的结构、酶和调节蛋白，该项目重点研究了孢子形成隔膜所需的两种蛋白质：FtsZ和隔膜特异性青霉素结合蛋白。这些实验将通过整合报告系统、突变分析和FtsZ转录所需蛋白质的分析来确定参与FtsZ在灰色链霉菌中发育调控的因素。将分离编码灰链霉菌隔膜特异性青霉素结合蛋白的基因，并测定其核苷酸序列；在另一项实验中，该基因将被干扰，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属性。为了繁殖，每个细胞必须分裂以产生可存活的子细胞。丝状细菌的细胞分裂分析是一个逻辑系统，用于研究对细胞分裂的正确时间和位置至关重要的分子事件。通过描述这些细菌的细胞分裂机制，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.