Studies of Bacterial Endospore Germination

摘要 细菌内孢子是地球上最持久和最具抵抗力的生命形式，能够在 休眠了几十年，并在一系列潜在的杀戮方法中存活下来，这是其他生物无法做到的 接近。令人惊讶的是，这些休眠的细胞能感觉到支持生长的环境，并恢复营养状态。 通过萌发过程在数小时内生长。对细胞结构和细胞结构的主要孢子特异性修改 细胞内容物驱动休眠和对杀灭处理的抗性，休眠孢子具有 在萌发过程中迅速逆转这些修改的机制。这项研究的长期目标是 充分了解决定孢子性质的细胞修饰的细节，以及决定孢子性质的机制 孢子开始萌发，一连串的事件导致新陈代谢和生长的恢复。 胞质蛋白在脱水的孢子核心中高度稳定，但大多数萌发活性 蛋白质位于膜的外表面，处于水合环境中，必须长期保持稳定。 休眠和其他机制的潜在身体攻击。拟议工作的压倒一切的假设 大多数发芽感觉和调节装置都存在于非常稳定的多蛋白质中 内孢子膜上或内孢子膜上的复合体，由于其最小的 膜流动性。拟议工作的具体目标是定义这些蛋白质的成分 复合体，以检查膜结构的潜在独特修改，并检查 孢子膜蛋白的降解及其对萌发进程的影响。拟议中的工作 还包括发现在萌发过程中扮演以前未知角色的基因的筛查。 孢子在几种人类和动物疾病的发生和污染中起着重要作用。 和食品的腐烂。孢子被用作高度稳定的载体，用于传递所需的 在许多工农业产品中的代谢活动，并已发展为稳定的载体 疫苗投放。在所有这些情况下，孢子萌发在该过程的成功中起着关键作用： 一种活动的致病机制或表现。因此，对发芽的充分了解可以驱使方法避免 或者改进这些流程。抑制发芽可以防止发病，同时刺激高效 萌发使孢子容易受到简单得多的去污方法的影响。刺激更高 萌发效率或发芽率可以提高基于孢子的产品的有效性。

Abstract Bacterial endospores are the most persistent and resistant forms of life on earth, able to remain in dormancy for decades and to survive a range of potential killing treatments that no other organisms can approach. Amazingly, these dormant cells can sense a growth-supportive environment and return to vegetative growth within hours through the process of germination. Major spore-specific modifications to cell structure and cellular content drive dormancy and resistance to killing treatments, and the dormant spores possess mechanisms to rapidly reverse these modifications during germination. The long-term goal of this study is to fully understand the details of cellular modifications that determine spore properties, the mechanism by which the spore initiates germination, and the cascade of events that lead to a resumption of metabolism and growth Cytoplasmic proteins are highly stabilized in the dehydrated spore core, but most germination-active proteins are on the membrane outer surface, in a hydrated environment, and must be stabilized during long-term dormancy and potential physical assault by other mechanisms. The overriding hypothesis of the proposed work is that the majority of the germination sensing and regulating apparatus is found in very stable multiprotein complexes in or on the inner spore membrane, which serves as a uniquely stable platform due to its minimal membrane fluidity. The specific goals of the proposed work are to define the components of these protein complexes, to examine potentially unique modifications of the membrane structure, and to examine the degradation of spore membrane proteins and effects this has on progression of germination. The proposed work also includes screens for discovery of genes that play previously unknown roles in the germination process. Spores play important roles in the initiation of several human and animal diseases, and in contamination and degradation of food products. Spores are used as the highly stable vehicles for the delivery of desirable metabolic activities in many industrial and agricultural products, and have been developed as stable vehicles for vaccine delivery. In all of these cases, spore germination plays a key role in the success of the process: pathogenesis or delivery of an activity. A full understanding of germination can therefore drive methods to avoid or improve these processes. Blocking germination can prevent pathogenesis, while stimulating highly efficient germination renders the spores susceptible to much simpler decontamination methods. Stimulating higher germination efficiency or rate can improve the effectiveness of a spore-based product.