Regulation of Metabolism and Pathogenicity Networks in Enterohemorrhagic Escherichia coli (EHEC)

肠出血性大肠杆菌 (EHEC) 代谢和致病性网络的调节

• 批准号: 71739137
• 负责人: Professor Dr. Herbert Schmidt
• 金额: --
• 依托单位: Fachgebiet Lebensmittelmikrobiologie und -hygiene (150a)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/71739137?language=en
• 关键词: Regulation; Metabolism; Pathogenicity; Networks; Enterohemorrhagic

Enterohemorrhagic Escherichia coli (EHEC) are serious causative agents of food-borne infections and can cause a broad range of intestinal and extraintestinal diseases. One of the major transmission pathways of EHEC from animal to man occurs by the alimentary uptake of raw or undercooked foods. The different environment (food)- and host-specific (human gastrointestinal tract) nutrient supply may induce specific metabolic and virulence-associated regulons in EHEC. However, these mechanisms are largely undescribed. In this project we will investigate the differential proteomic and metabolic responses of EHEC strains to host- and environment-specific growth conditions, such as food-related growth media, simulated ileal (SIEM) and colonic medium (SCEM), aerobic/anaerobic growth conditions, and water activity. It will be analyzed how essential metabolic systems (e.g. carbon nutrition) of EHEC react to specific environments and how this is linked to pathogenicity and the expression of virulence factors. The regulation of determinants that facilitates the first steps of infection (e.g. expression of fimbriae, membrane transport systems, shift to anaerobic respiration) will be in the focus of our work. Qualitative and quantitative differential analysis of the proteome of EHEC strains under particular environmental and host growth conditions will be performed following separation by fluorescence 2-dimensional-gelelectrophoresis (2-DIGE). Metabolic pathways, i.e. carbon metabolism, will be investigated by isotopologue profiling using (U-13C6) glucose. The influence of the differentially expressed proteome and metabolome on EHEC pathogenicity will primarily be established in intestinal cell culture models and in a later phase of the project with in vitro organ cultures (IVOC). These experiments lead to a better understanding of the mechanisms of survival and competition of EHEC in the gut and the influence of the metabolic system to EHEC-pathogenicity.

肠出血性大肠杆菌（EHEC）是严重的食源性感染病原体，可引起广泛的肠道和肠外疾病。肠出血性大肠杆菌从动物传播到人的主要途径之一是通过消化道摄入生的或未煮熟的食物。不同的环境（食物）和宿主特异性（人胃肠道）营养供应可能会诱导特定的代谢和毒力相关调节子在EHEC。然而，这些机制在很大程度上没有描述。在这个项目中，我们将研究肠出血性大肠杆菌菌株的差异蛋白质组学和代谢反应的主机和环境特定的生长条件，如食品相关的生长介质，模拟回肠（SIEM）和结肠培养基（SCEM），有氧/厌氧生长条件，和水的活性。将分析肠出血性大肠杆菌的基本代谢系统（如碳营养）如何对特定环境作出反应，以及这如何与致病性和毒力因子的表达相关联。促进感染的第一步（例如菌毛的表达，膜运输系统，转变为无氧呼吸）的决定因素的调节将是我们工作的重点。采用荧光双向凝胶电泳（2-DIGE）技术对特定环境和宿主生长条件下的肠出血性大肠杆菌菌株蛋白质组进行定性和定量差异分析。将使用（U-13 C6）葡萄糖通过同位素分析研究代谢途径，即碳代谢。差异表达的蛋白质组和代谢组对肠出血性大肠杆菌致病性的影响将主要在肠细胞培养模型中建立，并在该项目的后期阶段与体外器官培养物（IVOC）一起建立。这些实验有助于更好地了解肠出血性大肠杆菌在肠道中的生存和竞争机制以及代谢系统对肠出血性大肠杆菌致病性的影响。