Function of the Bacillus anthracis Spore Carboydrate

描述(申请人提供)：由于肺炭疽病的高度致命性，炭疽杆菌孢子的容易产生和储存，以及它们在攻击后在环境中的生存，这种细菌已成为生物武器和生物恐怖主义的主要病原体。对肺部炭疽病患者进行有效抗生素治疗的机会窗口是如此之小，以至于接种疫苗是目前预防这种疾病的最好方法。炭疽杆菌的孢子是真正的感染源，也是与宿主巨噬细胞第一次相互作用的有机体的形式。最近的研究发现，孢子抗原是炭疽免疫的重要组成部分。我们已经确定了该孢子的一种独特的碳水化合物成分。目前还不知道碳水化合物在孢子的生物学中扮演了什么角色，从任何种类的细菌。在本项目中，我们将创建炭疽芽胞糖蛋白基因缺失的突变体。这些基因敲除对孢子碳水化合物含量的影响将通过质谱学来确定。将对突变细胞进行孢子形成缺陷的评估，并在体外对这些突变株的孢子进行抗性特性和萌发效率的鉴定。将评估外孢子菌糖蛋白的碳水化合物和蛋白质成分在增强对感染的免疫力方面的作用。将进行初步实验，以确定炭疽杆菌BCLA糖蛋白的丢失是否会影响该炭疽病原体的毒力特性。这些研究将提供信息，以评估孢子碳水化合物是否可用作炭疽疫苗的免疫原。这些结果将为未来一项更具体地将孢子表面结构与毒力相关并作为疫苗靶标的提议提供支持数据。

DESCRIPTION (provided by applicant): Because of the highly fatal nature of pulmonary anthrax, the ease of production and storage of the spores of B. anthracis, and their survival in the environment after an attack, this bacterium has become the primary agent in biowarfare and bioterrorism. The window of opportunity for effective antibiotic treatment of patients with pulmonary anthrax is so small that vaccination is the current best defense against the disease. The spore of B. anthracis is the actual infectious agent and the form of the organism that is involved with the first interactions with the host macrophages. Recent studies have found that spore antigens are an important component to immunity against anthrax. We have identified a unique carbohydrate component of the spore. It is not known what roles carbohydrates play in the biology of the spore, from any species of bacteria. In this project, we will create mutants, which deleted for B. anthracis spore glycoprotein genes. The effect of these gene knockouts on spore carbohydrate content will be determined by mass spectrometry. The mutant cells will be evaluated for defects in spore formation and the spores from these mutants characterized for their resistance properties and germination efficiency in vitro. The role of the carbohydrate and protein components of the exosporium glycoprotein in conferring immunity to infection will be assessed. Preliminary experiments will be carried out to determine if loss of the BclA glycoprotein of B. anthracis affects the virulence properties of this anthrax agent. These studies will provide the information to evaluate whether the spore carbohydrate would be useful as an immunogen in a vaccine against anthrax. The results will provide supporting data for a future proposal to more specifically correlate spore surface structures with virulence and as vaccine targets.