MORPHOGENETIC PROCESSES IN BACTERIAL SPORULATION

细菌孢子形成的形态发生过程

• 批准号: 3270098
• 负责人: Arthur I. Aronson
• 金额: $ 11.62万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-04-01 至 1987-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3270098
• 关键词: Bacillaceae; Bacillus cereus; Bacillus subtilis; bacterial antigens; bacterial genetics; clone cells; density gradient ultracentrifugation; electron microscopy; endotoxins; genetic manipulation; genetic mapping; genetic regulation; glutamate ammonia ligase; histogenesis; immunologic techniques; peptidases; radiotracer; sporogenesis; temperature sensitive mutant

The morphogenetic events required to form a unique microbial structure, the B. subtilis spore coats, will be studied. Specific coat polypeptides are being purified, antibodies prepared and used as probes to detect precursors, processing steps and to look for alternations in coat mutants. The mechansim of cross linking of coat polypeptides via dityrosine residues to form an insoluble coat fraction will be further studied. The antibodies will be used to detect clones of spore coat structural protein genes. We shall also attempt to clone a gene affecting germination and spore coat structure by using as a probe a clone of the closely linked leucine genes. Mutants altered in one or more post exponential proteases will be isolated, mapped and isogenic strains constructed. The physiological effects of such mutations on protein turnover, shift down adaptation and spore coat polypeptide (or other protein) processing will be studied. We have evidence for one protease involved in the latter events and shall purify the enzyme to determine specificity, inhibition and to study in vitro processing. We shall also further examine the function of a protein protease inhibitor produced early during sporulation by trying to obtain mutants with an altered inhibitor. Glutamine synthetase in B. subtilis, in contrast to many other organisms, does not appear to be controlled by an elaborate cascade mechanism nor by a series of regulatory genes. All mutants isolated to date map in or close to the structural gene and yet there is some regulation of the amount of enzyme produced, especially by a trans acting factor detectable in partial diploids. By appropriate cloning we shall define this trans acting factor, and sequence it as well as potential regulatory regions close to the structural gene. We shall also construct more diploids to do complementation studies with various classes of mutants. Clones of the structural gene will also be used for localized nutagenesis, especially deletions to construct strains devoid of any activity or antigen. The pleiotropic effects of such mutants on sporulation and catabolism will be examined.

形成独特微生物结构所需的形态发生事件， B。枯草芽孢杆菌孢子衣，将进行研究。 特异性外壳多肽是 纯化，制备抗体并用作探针以检测 前体，加工步骤，并寻找在大衣突变体的变化。 二酪氨酸残基交联外壳多肽的机理 将进一步研究形成不溶的涂层部分。 的抗体 将用于检测孢子外壳结构蛋白基因的克隆。 我们 我还将尝试克隆影响萌发和孢子衣的基因 通过使用紧密连锁的亮氨酸基因的克隆作为探针来构建。 将分离在一种或多种指数后蛋白酶中改变的突变体， 作图和构建等基因菌株。 这种药物的生理效应 蛋白质周转、下移适应和孢子衣突变 多肽（或其他蛋白质）加工将被研究。 我们有 一种蛋白酶参与后者事件的证据，并应纯化 确定酶的特异性、抑制性并进行体外研究 处理. 我们还将进一步研究蛋白质的功能 蛋白酶抑制剂在孢子形成早期产生， 突变体与改变抑制剂。 谷氨酰胺合成酶在B中。枯草杆菌，在 与许多其他生物不同，它似乎不受一种生物的控制。 也不是通过一系列调控基因。 所有 迄今分离的突变体定位在结构基因中或接近结构基因， 酶的产生量有一定的调节作用，特别是由 在部分二倍体中可检测到反式作用因子。 通过适当的克隆 我们将定义这个反作用因子，并对它进行排序， 结构基因附近的潜在调控区域。 我们亦会 构建更多的二倍体，与各纲进行互补研究 变种人 结构基因的克隆也将用于定位 诱变，特别是缺失，以构建缺乏任何 活性或抗原。 这些突变体对细胞的多效性影响 将检查孢子形成和孢子囊形成。