A cyclic di-GMP signaling system of spores of Bacillus anthracis

炭疽芽孢杆菌孢子的环状双 GMP 信号系统

• 批准号: 8969220
• 负责人: GEORGE C. STEWART
• 金额: $ 22.62万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8969220
• 关键词: Adhesions; Affect; Alanine Racemase; Animal Model; Animals; Anthrax disease; Architecture; Area; Bacillus (bacterium); Bacillus anthracis; Bacillus anthracis spore; Bacteria; Bacterial Spores; Biochemical; Biology; Bioterrorism; Cell Culture Techniques; Cells; Chimeric Proteins; Clostridium; Cutaneous; Cyclic Nucleotides; Data; Deletion Mutation; Disease; Enzymes; Funding; Future; Gene Deletion; Gene Silencing; Generations; Genes; Genetic; Germination; Glycoproteins; Goals; Human; Immune response; Immune system; Immunoelectron Microscopy; In Vitro; Individual; Infection; Inosine; Investigation; Lead; Location; Lung; Microbial Biofilms; Modeling; Molecular Profiling; Mus; Mutation; Nature; Nitric Oxide Synthase; Nucleoside Hydrolases; Oxidative Stress; Phagocytes; Physiological Processes; Pilum; Process; Proteins; Regulation; Reporter; Reporting; Reproduction spores; Resistance; Role; Route; Signal Transduction; Signaling Molecule; Structure; Surface; System; Testing; Therapeutic Intervention; TimeLine; Virulence; Western Blotting; Work; biothreat; cell motility; fitness; gastrointestinal; macrophage; member; mortality; mouse model; mutant; novel; pathogen; phosphoric diester hydrolase; public health relevance; research study; therapeutic development; vaccine development

 DESCRIPTION (provided by applicant): Bacillus anthracis is an endospore-forming zoonotic bacterium of significant concern as a bioterrorism agent. The route by which the spore gains access to a human host defines the nature of the resulting disease, cutaneous, gastrointestinal, or pulmonary. Gastrointestinal and pulmonary anthrax are associated with high mortality rates. The composition of the B. anthracis spore, especially its interspace and exosporium layers, is incompletely understood. Enzymes, including alanine racemase, inosine preferring nucleoside hydrolase, and nitric oxide synthase, are found in the outer spore coat, interspace, and exosporium layers. These enzymes are thought to function in spore germination and defense against the host innate immune system. We have identified the presence of proteins associated with the regulation of cyclic di-GMP levels in spores of B. anthracis. Cyclic di-GMP is an important regulator that has been identified in a number of bacterial pathogens. It is a critical regulator of a number of virulence attributes including biofilm formation, motility, intracellular survival, expression of surface adhesions, expression of pili, resistance to oxidative stress, and modulation of the host immune response. A role for this cyclic nucleotide regulator in spore biology, either sporulation or germination, has not been reported. We propose to study GGDEF domain-containing proteins whose expression profile and/or protein fusion studies indicate that they are spore proteins. Initial studies with one of these determinants have shown an effect on spore maturation. In this project, we will determine the location within the spores for these GGDEF proteins, the effects on spore structure and function associated with loss of these proteins both singly and in combination, and the effects on spore biology in macrophage cell cultures and a mouse model of infection. The goals of these experiments are to determine the roles of the GGDEF proteins on sporulation, germination, and virulence. Because the spore is the infectious form of this zoonotic pathogen, this information is important to our understanding of the B. anthracis infectious process and may identify potential targets for therapeutic intervention against the initial steps in B. anthracis infections. Information obtained from this study may have broader applicability to understanding the infectious process of other endospore-forming bacterial pathogens.

 描述（由申请人提供）：炭疽芽孢杆菌是一种形成内生孢子的人畜共患细菌，作为一种生物恐怖剂而备受关注。孢子进入人类宿主的途径决定了所产生的皮肤、胃肠道或肺部疾病的性质。胃肠道炭疽和肺炭疽与炭疽芽孢杆菌孢子的组成，尤其是其间隙和高度有关。外孢子层中的酶，包括丙氨酸消旋酶、肌苷偏爱核苷水解酶和一氧化氮合酶，存在于孢子外衣、间隙和外孢子层中，这些酶被认为在孢子萌发和防御孢子的过程中发挥作用。我们已经鉴定出与芽孢杆菌孢子中环二 GMP 水平调节相关的蛋白质的存在。环状二-GMP 是许多细菌病原体中的重要调节因子，它是许多毒力属性的关键调节因子，包括生物膜形成、运动、细胞内存活、表面粘附的表达、菌毛的表达、这种环核苷酸调节剂在孢子生物学（孢子形成或萌发）中的作用尚未见报道。含有 GGDEF 结构域的蛋白质，其表达谱和/或蛋白质融合研究表明它们是孢子蛋白，这些决定因素之一的初步研究表明它们对孢子成熟有影响。 GGDEF 蛋白，与这些蛋白单独和组合丢失相关的对孢子结构和功能的影响，以及对巨噬细胞培养物和小鼠感染模型中孢子生物学的影响。实验的目的是确定 GGDEF 蛋白对孢子形成、萌发和毒力的作用，因为孢子是这种人畜共患病原体的感染形式，这一信息对于我们了解炭疽芽孢杆菌感染过程非常重要，并可能确定潜在的目标。针对炭疽芽孢杆菌感染的初始步骤的治疗干预从这项研究中获得的信息可能具有更广泛的适用性，以了解其他内生孢子形成细菌病原体的感染过程。