DNA Microarray analysis of Clostridium botulinum

描述(申请人提供)：肉毒杆菌是一种厌氧芽胞形成细菌，它产生肉毒杆菌神经毒素，肉毒杆菌神经毒素是最有效的蛋白质毒素，已知会导致人和动物的肉毒杆菌中毒。肉毒杆菌神经毒素(A-G)有7种血清型，它们来自不同的肉毒杆菌菌株，它们在生理和系统发育上是不同的。神经毒素基因簇包含神经毒素基因和毒素相关蛋白基因，位于不同肉毒弧菌基因组的不同部分，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体的生物学，以及这些神经毒素在肉毒杆菌及其相关物种的生理和进化中的作用。这项研究利用了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研究神经毒素复合体产生的作用以及肉毒杆菌的生理和进化。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。产毒菌株特有的基因将被识别并进一步鉴定。在特定的目标2中，我们将确定肉毒杆菌神经毒素生产水平对肉毒杆菌生长阶段依赖的基因表达谱的影响。利用基因芯片分析，我们将检测和比较产毒野生型菌株和毒素缺陷型突变菌株之间的全球基因转录图谱。将分析神经毒素对细胞功能、生长和产孢量的影响。在拟议的研究中获得的知识将有助于我们了解肉毒杆菌毒素产生的生物学，目的是有助于了解有关神经毒素的知识，并开发预防肉毒杆菌中毒的新策略。与公共卫生相关：肉毒杆菌产生肉毒杆菌神经毒素，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，细菌及其神经毒素被归类为“A类”精选制剂，因为它们可能用作生物武器。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，目的是有助于了解有关神经毒素的知识，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.