Bacteriophage interactions with enteric pathogens

项目摘要 噬菌体和病毒如何识别它们特定的宿主细胞受体对于绝大多数人来说是未知的 物种。长期目标是理解结构和机制背后的一般原则，这些结构和机制 控制噬菌体的宿主细胞进入。这项提案的目标是确定结构，以及 肠道病原体中噬菌体如何利用外膜蛋白和内膜蛋白进行感染的机制 如志贺氏菌、大肠杆菌和沙门氏菌。中心假设是存在保守的蛋白质结构 以及管理大多数噬菌体：宿主对的噬菌体进入的相应机制。我们预测 噬菌体进入细胞表面通常需要一些通用的特征，其他细胞表面也是如此 可能特定于单个噬菌体的特征：宿主对。拟议工作的基本原理是 我们将在介导噬菌体感染的肠道病原体中识别关键的受体蛋白，这是一种更好的 对这些相互作用的了解将为识别新疗法或 对现有的进行改进。我们将采用概念和技术相结合的方式进行这项研究 涉及遗传学、生物化学和生物物理学的创新。这些创新包括最近在 我的实验室，以及更成熟的微生物技术。这项拟议的研究意义重大， 由于它将提供有关噬菌体如何停靠到其特定宿主的结构性和机械性洞察，因此 生产性感染的必要步骤。这项工作还将开发资源，供其他人使用 研究人员。例如，建议的工作将开发出广泛适用的复杂转座子和单转座子 基因缺失文库，这将极大地推动志贺菌的研究，因为目前还没有这样的基因 工具包已经存在。这项工作的预期结果将提供对噬菌体如何附着在 宿主包括哪些蛋白质和相互作用是普遍需要的，哪些是个体特有的 噬菌体：宿主对。此外，我们还将获得对蛋白质的原子水平的理解：蛋白质结合 控制感染的相互作用和瞬时感染中间状态。原子级详细信息，例如如何 与宿主结合的噬菌体对于设计新的治疗方法或增强现有的治疗方法至关重要。

Project Summary How phages and viruses recognize their specific host cell receptors is not known for the vast majority of species. The long-term goal is to understand the general principles behind the structures and mechanisms that control host cell entry for bacteriophages. The objective of this proposal is to determine the structures, and mechanisms of how phages use both outer and inner membrane proteins for infection in enteric pathogens such as Shigella, E.coli and Salmonella. The central hypothesis is that there are conserved protein structures and corresponding mechanisms that govern phage entry for the majority of phage:host pairs. We predict that there are universal cell surface features that are generally required for phage entry, and also other cell surface features that may be specific to individual phage:host pairs. The rationale underlying the proposed work is that we will identify key receptor proteins in enteric pathogens that mediate phage infection, and that a better understanding of these interactions will provide physical targets for either identifying new therapies or improving existing ones. We will pursue this research using a combination of conceptual and technological innovations involving genetics, biochemistry and biophysics. These include innovations recently developed in my laboratory, as well as more established microbiological techniques. The proposed research is significant, as it will provide both structural and mechanistic insights into how phages dock to their specific hosts, a necessary step for productive infection. This work will also develop resources that will be used by other researchers. For example, the proposed work will develop widely-applicable complex transposon and single gene deletion libraries, which will greatly propel research forward in Shigella, as currently no such genetic toolkit exists. The expected outcome of this work will provide a basic understanding of how phages attach to hosts including which proteins and interactions are universally required, and which are specific to individual phage:host pairs. Additionally, we will gain an atomic level understanding of the protein:protein binding interactions and transient infection intermediate states that control infection. Atomic level details, such as how phages bind to their hosts are critical for engineering new therapeutics or enhancing existing ones.