Function of the Bacillus anthracis Spore Carboydrate

描述（由申请人提供）：由于肺炭疽的高度致命性，炭疽芽孢杆菌易于生产和储存，以及它们在攻击后在环境中存活，这种细菌已成为生物战和生物恐怖主义的主要病原体。对肺炭疽患者进行有效抗生素治疗的机会之窗非常小，因此疫苗接种是目前对抗该疾病的最佳防御手段。炭疽芽孢杆菌的孢子是真正的传染因子，也是与宿主巨噬细胞第一次相互作用的生物体的形式。最近的研究发现，孢子抗原是炭疽免疫的重要组成部分。我们已经确定了孢子中一种独特的碳水化合物成分。目前尚不清楚碳水化合物在任何一种细菌的孢子的生物学中起什么作用。本课题将构建缺失炭疽芽孢杆菌糖蛋白基因的突变体。这些基因敲除对孢子碳水化合物含量的影响将通过质谱测定。将评估突变细胞的孢子形成缺陷，以及这些突变体的孢子在体外的抗性和萌发效率。将评估外孢子糖蛋白的碳水化合物和蛋白质成分在赋予感染免疫中的作用。初步实验将进行，以确定是否损失的BclA糖蛋白的炭疽杆菌影响该炭疽剂的毒力特性。这些研究将为评估孢子碳水化合物是否可作为炭疽疫苗的免疫原提供信息。结果将为未来提出更具体地将孢子表面结构与毒力和作为疫苗靶点相关联的建议提供支持数据。

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.