S. typhimurium Genes Required for Colonization of Cattle

牛定植所需的鼠伤寒沙门氏菌基因

• 批准号: 6521702
• 负责人: HELENE L ANDREWS-POLYMENIS
• 金额: $ 9.37万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6521702
• 关键词: Salmonella infections; Salmonella typhimurium; bacteria infection mechanism; bacterial DNA; bacterial food poisoning; bacterial genetics; colitis; cow; disease /disorder model; epizootiology; host organism interaction; immature animal; microorganism population study; southern blotting; species difference; virulence

DESCRIPTION (provided by applicant): S. typhimurium is the most common cause of foodborne illness with lethal outcome in the US. The ability of S. typhimurium to consistently contaminate our food supply, creates an urgent need for better understanding of the molecular mechanisms that allow this pathogen to persist successfully in food producing animals. Epidemiological surveillance strongly suggests that pigeon adapted S. typhimurium variants (phage types DT2 and DT99) that cause fatal pigeon paratyphoid do not persist in cattle. The objective of this proposal is to identify the genes responsible for the epidemiologic success of S. typhimurium.in cattle through genomic comparison and characterize their function using the calf model of enterocolitis. The first specific aim of this proposal is to evaluate the virulence and persistence of S. typhimurium pigeon adapted variants in calves. The calf ligated ileal loop model will be used to evaluate the ability of pigeon variants to cause fluid accumulation, inflammation and tissue damage in the calf small intestine, and persistence in calves will be studied using oral models of infection. The second specific aim of this proposal is to identify genes present in S. typhimurium strain LT2 but absent from pigeon isolates. To identify LT2 specific genes unique to cattle isolates we will establish a epidemiological correlation within a large number of S.typhimurium isolates by southern blotting. The final specific aim of this proposal is to test unique regions of DNA isolated from S. typhimurium cattle variants for the ability to alter host specificity of pigeon adapted S. typhimurium isolates. Dr. Andrews-Polymenis completed her Ph.D. in the laboratory of Dr. Ralph Isberg, identifying novel factors necessary for intracellular growth of Legionella pneumophila. She completed her D.V.M. cum laude at Texas A&M University College of Veterinary Medicine in May 2001. Having a strong interest in bacterial pathogenesis and in veterinary medicine, Dr. Andrews-Polymenis' career goal is to become an independent investigator at the interface between these two areas. The research collaboration between Dr. Baumler in the Texas A&M Health Science Center and Dr. Adams in the College of Veterinary Medicine provides a unique opportunity to achieve this career goal.

描述（由申请人提供）：鼠伤寒沙门氏菌是美国粮食疾病的最常见原因，在美国具有致命的结果。鼠伤伤口一直污染我们的食物供应的能力，迫切需要更好地理解分子机制，从而使这种病原体能够成功地在食品生产动物中持续存在。流行病学监测强烈表明，鸽子适应了鼠伤寒沙门氏菌的变体（噬菌体类型DT2和DT99），导致致命的鸽子甲状腺par虫不会持续在牛中。该提案的目的是通过基因组比较来确定牛链球菌的流行病学成功的基因，并使用小肠结肠炎的小腿模型来表征其功能。该提案的第一个具体目的是评估猪肉猪链球菌的毒力和持久性。小腿结扎的回肠环模型将用于评估鸽子变体在小肠中引起液体积累，炎症和组织损伤的能力，并将使用口服感染模型来研究小牛的持久性。该提案的第二个特定目的是鉴定鼠伤寒链球菌菌株LT2中存在的基因，但鸽子分离株不存在。为了鉴定牛分离株独有的LT2特异性基因，我们将通过Southern印迹在大量的二磷菌分离株中建立流行病学相关性。该提案的最终具体目的是测试从鼠伤寒链霉菌牛变体中分离出的DNA的独特区域，以改变适应鸽子适应性伤寒链球菌分离株的宿主特异性。 安德鲁斯·波利梅尼斯博士完成了博士学位。在拉尔夫·伊斯伯格（Ralph Isberg）博士的实验室中，确定了肺炎军团菌的细胞内生长所必需的新因素。她完成了D.V.M. 2001年5月，得克萨斯州A＆M大学兽医学院的优异成绩。对细菌发病机理和兽医医学有浓厚的兴趣，安德鲁斯·波利梅尼斯（Andrews-Polymenis）博士的职业目标是成为这两个领域界面的独立研究人员。 得克萨斯州A＆M健康科学中心鲍姆勒博士与兽医学院的亚当斯博士之间的研究合作为实现这一职业目标提供了独特的机会。