Salmonella Genes Associated with Colonization of Specific Hosts

与特定宿主定植相关的沙门氏菌基因

• 批准号: 7584383
• 负责人: MICHAEL MCCLELLAND
• 金额: $ 48.72万
• 依托单位: VACCINE RESEARCH INSTITUTE OF SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7584383
• 关键词: Animal Experiments; Animal Model; Animals; Antibiotic Resistance; Biological Assay; Chickens; Cistrons; Code; Communities; DNA; Data; Dissection; Dose; Escherichia coli; Family suidae; Founder Generation; Funding; Genes; Genome; Genomics; Harvest; Human; Hybridization Array; In Vitro; Individual; Infection; Knock-out; Label; Lead; Libraries; Location; Medical Economics; Methods; Modeling; Molecular; Monitor; Mus; Mutate; Neomycin; Oligonucleotide Microarrays; Output; Phylogenetic Analysis; Play; Population Sizes; Predisposition; Process; Proteins; Relative (related person); Research; Resources; Role; Salmonella; Salmonella enterica; Salmonella typhimurium; Sampling; Scheme; Specificity; Surveys; Technology; Testing; Time; Tissues; Virulence Factors; Wild Animals; animal tissue; base; design; fitness; genetic selection; genome sequencing; internal control; intraperitoneal; knockout gene; mutant; new technology; novel; novel therapeutics; pathogen; research study; tool

Salmonella enterica serovar Typhimurium has a very broad host range and can colonize different Phyla. To date, only a small fraction of its genome has been surveyed for genes that differ in their contribution to colonization of different hosts. This project is designed to determine which Typhimurium mutants are unable to fully compete with wild type during colonization of three vertebrate host species, selected for their phylogenetic diversity and known susceptibility to Typhimurium infection: mouse, pig, and chicken. A pool of specific knockout mutants in every non-essential Typhimurium gene in vitro (~3900 knockouts) will be delivered intragastrically to the model animals. Short-term colonization in the gut will be monitored by dissection of host tissues at three days post infection. An oligonucleotide array with a novel design will be used to identify all mutants that become rarer during competitive colonization, indicating a role of that gene in the process. A novel fluctuation test will assure that only appropriate experiments will be applied to arrays. We have confirmed that the proposed assay detects almost all genes that are known to contribute to intraperitoneal and intragastric infection in the mouse. If the data suggest that a known colonization mechanism in one host may not be used in other hosts, this will be independently confirmed by testing single exemplar gene knockout mutants in these species. Novel host-restricted colonization mechanisms are beyond the scope of this two year project and will be studied, only if time and resources permit.

肠沙门氏菌鼠伤寒血清型具有非常广泛的宿主范围，可以定植于不同的门。迄今为止，仅对其基因组的一小部分进行了调查，以了解对不同宿主的定植贡献不同的基因。该项目旨在确定哪些鼠伤寒突变体在三种脊椎动物宿主物种的定植过程中无法与野生型完全竞争，这三种脊椎动物宿主物种是根据其系统发育多样性和已知的鼠伤寒感染易感性而选择的：小鼠、猪和鸡。体外每个非必需鼠伤寒基因的特定敲除突变体库（约 3900 个敲除）将被灌胃至模型动物体内。通过在感染后三天解剖宿主组织来监测肠道中的短期定植。具有新颖设计的寡核苷酸阵列将用于识别在竞争性定植过程中变得更加稀有的所有突变体，表明该基因在此过程中的作用。新颖的波动测试将确保只有适当的实验才会应用于阵列。我们已经证实，所提出的检测方法可以检测到几乎所有已知导致小鼠腹膜内和胃内感染的基因。如果数据表明一种宿主中已知的定植机制可能无法在其他宿主中使用，则将通过测试这些物种中的单个示例基因敲除突变体来独立证实这一点。新的宿主限制性定殖机制超出了这个为期两年的项目的范围，只有在时间和资源允许的情况下才会进行研究。