Genetic studies in enteric bacteria

肠道细菌的遗传学研究

• 批准号: 3684-2008
• 负责人: Sanderson, Kenneth
• 金额: $ 2.91万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=498192
• 关键词: Genetic; studies; enteric; bacteria

The objective of work in my laboratory is to use the methods of genetics and genomics to reveal the basis for the astonishing degree of genetic variability which is found in bacterial populations. The over 2000 serovars of Salmonella vary dramatically, including S. enterica serovar Typhimurium which causes gastroenterites in many animals and humans, and S. enterica serovar Typhi which causes a much more serious enteric fever (Typhoid) only in humans, and thousands of other forms. I began studies in the 1960s by constructing a linkage map of the chromosome of S. Typhimurium with less than 200 genes mapped; in 2001 a collaborative effort with other labs sequenced about 4800 genes in the genome of the same bacterium. Sequence reveals that there are blocks of DNA, called Islands, in different serovars, which are present in some, but missing from others, and these produce different properties and virulence. Typhi has an Island which controls a virulence antigen; we have studied the loss of that island. In the coming grant period we have two major goals. (1) Comparative genomic analysis in enteric bacteria. We will be completing seven genomes which are being sequenced in our collaboration with Washington Univ. Genome Sequencing Center. We take part in gene annotation in these seven genomes, and overall comparisons of the genomes of all sequences to reveal phylogenetics, and to explain the basis for different phenotypes. (2) Study of the presence and role of prophages in bacterial genomes. Prophages are present in most genomes, e.g., S. Typhimurium strain LT2 has four. Whole genome sequencing reveals putative prophages based on bioinformatic studies, but we propose biological studies which will reveal if these are active prophages which can form free phage particles and transmit genes to other hosts.

我的实验室工作的目的是利用遗传学和基因组学的方法来揭示细菌种群中惊人的遗传变异程度的基础。 沙门氏菌的2000多个血清型差异很大，包括沙门氏菌。肠道血清型鼠伤寒沙门氏菌（S.伤寒是一种只在人类中引起严重得多的肠道发热（伤寒）的肠道血清型伤寒，以及数千种其他形式。 我在20世纪60年代开始研究，构建了S染色体的连锁图。在2001年，与其他实验室的合作努力对同一种细菌的基因组中约4800个基因进行了测序。 序列显示，在不同的血清型中存在称为岛的DNA块，它们存在于一些血清型中，但在另一些血清型中缺失，并且这些血清型产生不同的特性和毒力。 伤寒有一个控制毒力抗原的岛;我们已经研究了那个岛的丧失。 在接下来的一段时间里，我们有两个主要目标。 (1)肠道细菌的比较基因组分析。 我们将完成七个基因组，这些基因组正在与华盛顿大学基因组测序中心合作进行测序。我们参与了这七个基因组的基因注释，并对所有序列的基因组进行了总体比较，以揭示遗传学的差异，并解释不同表型的基础。 (2)细菌基因组中前噬菌体的存在和作用的研究。 脯氨酸存在于大多数基因组中，例如，S.鼠伤寒菌株LT 2有四个。 全基因组测序揭示了基于生物信息学研究的推定的前噬菌体，但是我们提出了生物学研究，其将揭示这些是否是可以形成游离噬菌体颗粒并将基因传递到其他宿主的活性前噬菌体。