DNA Microarray analysis of Clostridium botulinum

描述（由申请人提供）：肉毒梭菌是一种厌氧孢子形成细菌，产生肉毒神经毒素，肉毒神经毒素是最有效的蛋白质毒素，已知会导致人类和动物肉毒杆菌中毒。肉毒杆菌神经毒素有七种血清型 (A - G)，由不同的肉毒杆菌菌株产生，在生理学和系统发育上各不相同。含有神经毒素和毒素相关蛋白基因的神经毒素基因簇位于不同肉毒杆菌菌株基因组的不同部分，表明该基因簇可能是可移动的。 PI 研究的总体目标是了解神经毒素复合物的生物学以及这些神经毒素在肉毒梭菌和相关物种的生理和进化中的作用。这里提出的研究利用了 NIH/NIAID 赞助的病原体功能基因组资源中心最近提供的 A 型肉毒杆菌 DNA 微阵列。我们将使用这些微阵列芯片在全基因组水平上检查神经毒素复合物产生的作用以及肉毒杆菌的生理学和进化。在具体目标 1 中，我们将进行比较基因组微阵列分析，以表征各种 A 型肉毒杆菌菌株的基因组，并将它们与未获得毒素基因簇的菌株进行比较。产毒素菌株特有的基因将被鉴定并进一步表征。在具体目标 2 中，我们将确定肉毒杆菌对肉毒杆菌神经毒素产生水平的生长阶段依赖性基因表达谱。使用微阵列分析，我们将检查和比较产生毒素的野生型菌株和缺乏毒素的突变菌株之间的全局基因转录谱。将分析神经毒素对细胞功能、生长和孢子形成的影响。在拟议的研究中获得的知识将帮助我们了解肉毒杆菌毒素产生的生物学，旨在促进有关神经毒素的知识体系并开发预防肉毒杆菌中毒的新策略。公共健康相关性：肉毒杆菌产生肉毒神经毒素，这是已知的导致人类和动物肉毒杆菌中毒的最有效的蛋白质毒素。由于毒素的效力，该细菌及其神经毒素被归类为“A 类”精选制剂，因为它们具有作为生物武器的潜在用途。拟议的研究有助于进一步了解肉毒杆菌毒素产生的生物学，旨在增进有关神经毒素的知识体系并开发预防肉毒杆菌中毒的新策略。

DESCRIPTION (provided by applicant): Clostridium botulinum is an anaerobic spore-forming bacterium that produces botulinum neurotoxin, the most potent protein toxin, which is known to cause botulism in humans and animals. There are seven serotypes of botulinum neurotoxins (A - G), produced from different strains of C. botulinum, that are physiologically and phylogenetically distinct. The neurotoxin gene cluster, containing the genes for the neurotoxin and the toxin associated proteins, is located on different parts of the genome in different C. botulinum strains, indicating that the gene cluster may be mobile. The overall goal of the PI's research is to understand the biology of the neurotoxin complex and the roles of these neurotoxins in the physiology and evolution of C. botulinum and related species. The study proposed here takes advantage of the recently available C. botulinum type A DNA microarray from NIH/NIAID sponsored Pathogen Functional Genomics Resource Center. We will use these microarray chips to examine, at the whole genome level, the role of neurotoxin complex production and the physiology and evolution of C. botulinum. In Specific Aim 1, we will perform comparative genomic microarray analyses to characterize the genomes of various C. botulinum type A strains and compare them to strains that did not acquire the toxin gene cluster. Genes unique to the toxin-producing strains will be identified and further characterized. In Specific Aim 2, we will determine the growth phase-dependent gene expression profiling of C. botulinum in response to the botulinum neurotoxin production levels. Using the microarray analyses, we will examine and compare the global gene transcriptional profiles between toxin-producing wild-type strains and toxin-deficient mutant strains. The impacts of the neurotoxin on cellular functions, growth and sporulation will be analyzed. The knowledge gained in the proposed studies will help us understand the biology of toxin production in C. botulinum with the intent of contributing to the body of knowledge about the neurotoxin and developing novel strategies to prevent botulism. PUBLIC HEALTH RELEVANCE: Clostridium botulinum produces botulinum neurotoxin, which is the most potent protein toxin known to cause botulism in humans and animals. Due to the potency of the toxin, the bacterium and its neurotoxins are classified as the "Category A" Select Agents for their potential use as biological weapons. The proposed studies allow further understanding of the biology of toxin production in C. botulinum with the intent of contributing to the body of knowledge about the neurotoxin and developing novel strategies to prevent botulism.