Identification of Salmonella Genes Important for Systemic Colonization

鉴定对系统定植重要的沙门氏菌基因

• 批准号: 7937069
• 负责人: HELENE L ANDREWS-POLYMENIS
• 金额: $ 40.26万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-25 至 2013-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7937069
• 关键词: Acquired Immunodeficiency Syndrome; Acute; Africa South of the Sahara; Age; Animal Model; Animals; Area; Bacteremia; Bacteria; Bacterial Proteins; Biological Assay; Biological Models; Candidate Disease Gene; Cause of Death; Cells; Cessation of life; Child; Cistrons; Collection; Complement; Development; Disadvantaged; Disease; Essential Genes; Frequencies; Gene Deletion; Gene Proteins; Genes; Genetic; Genetic Screening; Genome; Gentamicins; Goals; HIV; Hour; Immune system; Immunocompromised Host; In Vitro; Individual; Infection; Invaded; Lead; Libraries; Methods; Modeling; Molecular; Molecular Genetics; Mus; Oligonucleotide Microarrays; Organ; Organism; Parasites; Persons; Phenotype; Process; Public Health; Relative (related person); Resistance; Resources; Salmonella; Salmonella enterica; Salmonella infections; Salmonella typhimurium; Screening procedure; Serotyping; Site; Spleen; Systemic disease; Systemic infection; Therapeutic Agents; Transcript; Vaccines; Virulence; Virus; Work; antimicrobial; base; combat; deletion library; fitness; foodborne; foodborne illness; gene function; genetic manipulation; genome sequencing; high throughput screening; in vivo; intraperitoneal; macrophage; mortality; mutant; new technology; novel; pathogen; promoter; public health relevance; recombinase; tool; tool development

DESCRIPTION (provided by applicant): We will use the power of complete genome sequences and forward genetics to identify novel genes that allow a bacterial pathogen to colonize systemic organs in murine models. Non-typhoidal Salmonella (NTS) are food-borne bacterial pathogens that cause hundreds of millions of cases of diarrheal disease and hundreds of thousands of deaths due to bacteremia annually worldwide. Salmonella enterica serotype Typhimurium is an appropriate model to determine the requirements for systemic infection by NTS as this serotype causes more cases of NTS bacteremia, in children under the age of 5 and in HIV infected individuals, than any other serotype. The availability of complete genome sequence information, the ease of genetic manipulation, and the availability of numerous animal models make serot. Typhimurium an excellent model system. We have generated a collection of 1030 targeted deletion strains in serot. Typhimurium (approximately 25% of the genome), developed a novel oligonucleotide microarray to assay this collection of mutants, and begun forward genetic screening of this mutant collection both in vitro and in vivo in murine models of systemic colonization. We wish to complete the development of these tools and progress to more comprehensive studies of a subset of genes involved in systemic colonization a process that occurs during NTS bacteremia caused by this organism. We will approach this goal by: 1. Completion of our deletion library in all non-essential genes in Salmonella Typhimurium, 2. Screening our complete deletion collection in murine models to identify new genes involved in systemic colonization, 3. Confirming each mutant as defective for systemic colonization, 4. Characterizing mutants that are defective for systemic colonization for their ability to associate with, invade, and replicate in cultured macrophages. PUBLIC HEALTH RELEVANCE: Salmonella is a leading cause of food borne illness, causing ~1.4 million cases of diarrheal disease per year and is the single most common cause of death from food-borne illnesses associated with viruses, parasites or bacteria in the US primarily in immunocompromised persons. In young children and HIV-infected individuals, non-typhoidal Salmonellae (NTS) frequently cause systemic infection that is associated with high mortality. The rise of AIDS in many parts of the world, notably in sub- Saharan Africa, has resulted in a dramatic increase in the frequency of NTS-associated systemic infections. The work described in this project will provide novel targets for vaccines and treatments for acute systemic disease that results from Salmonella infection. This work will have a direct impact on public health.

描述（由申请人提供）：我们将利用完整基因组序列和正向遗传学的力量来识别允许细菌病原体在小鼠模型中定植全身器官的新基因。非伤寒沙门氏菌 (NTS) 是食源性细菌病原体，每年在全世界引起数亿例腹泻病，并导致数十万人因菌血症死亡。肠沙门氏菌血清型鼠伤寒是确定 NTS 全身感染要求的合适模型，因为与任何其他血清型相比，该血清型在 5 岁以下儿童和 HIV 感染者中引起更多 NTS 菌血症病例。完整基因组序列信息的可用性、基因操作的简易性以及大量动物模型的可用性使得塞洛特成为可能。鼠伤寒菌是一个优秀的模型系统。我们在血清中生成了 1030 个靶向缺失菌株的集合。 Typhimurium（约占基因组的 25%）开发了一种新型寡核苷酸微阵列来分析该突变体集合，并开始在系统定植的小鼠模型中在体外和体内对该突变体集合进行正向遗传筛选。我们希望完成这些工具的开发，并进一步对参与系统定植的基因子集进行更全面的研究，系统定植是由该生物体引起的 NTS 菌血症期间发生的过程。我们将通过以下方式实现这一目标：1. 完成鼠伤寒沙门氏菌所有非必需基因的缺失文库，2. 在小鼠模型中筛选我们完整的缺失库，以鉴定参与系统定植的新基因，3. 确认每个突变体在系统定植方面存在缺陷，4. 表征在系统定植方面存在缺陷的突变体在培养物中的关联、入侵和复制能力。 巨噬细胞。公共卫生相关性：沙门氏菌是食源性疾病的主要原因，每年导致约 140 万例腹泻病，并且是美国与病毒、寄生虫或细菌相关的食源性疾病死亡的最常见原因，主要是免疫功能低下的人群。在幼儿和 HIV 感染者中，非伤寒沙门氏菌 (NTS) 经常引起全身感染，并导致高死亡率。艾滋病在世界许多地区，特别是在撒哈拉以南非洲地区的流行，导致与 NTS 相关的系统性感染的频率急剧增加。该项目描述的工作将为沙门氏菌感染引起的急性全身性疾病的疫苗和治疗提供新的靶点。这项工作将对公众健康产生直接影响。