Understanding the molecular mechanisms and biological functions of a novel bleach-sensing bacterial receptor in shaping host-associated bacterial populations in response to host inflammation

了解新型漂白剂感应细菌受体在塑造宿主相关细菌群体以响应宿主炎症方面的分子机制和生物学功能

• 批准号: 10654973
• 负责人: Arden Baylink
• 金额: $ 24.9万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-16 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10654973
• 关键词: Animal Model; Animals; Antioxidants; Bacteria; Bacterial Infections; Binding; Biochemical Pathway; Biological; Biological Assay; Biological Process; Biological Testing; Biology; Chemistry; Chemoreceptors; Chemotaxis; Chronic; Colon Carcinoma; Communicable Diseases; Crystallography; Cysteine; Disease; Engineering; Enzyme-Linked Immunosorbent Assay; Enzymes; Escherichia coli; Feedback; Fingers; Gastric Tissue; Gastric ulcer; Genetic Engineering; Goals; Helicobacter pylori; Human; Hypochlorous Acid; Immune; Immune system; In Situ; In Vitro; Infection; Infectious Diseases Research; Inflammation; Inflammation Process; Inflammatory Bowel Diseases; Invaded; Investigation; Knowledge; Learning; Leukocytes; Ligands; Measures; Metals; Microbial Biofilms; Microscopy; Modeling; Molecular; Molecular Conformation; Mus; Nutrient; Oregon; Oxidants; Oxidation-Reduction; Oxides; Pathogenicity; Pattern; Peroxidases; Physiological; Play; Point Mutation; Population; Process; Production; Proteins; Reaction; Research; Research Personnel; Role; Salmonella; Salmonella typhimurium; Second Messenger Systems; Shapes; Signal Transduction; Signaling Protein; Site; Source; Spatial Distribution; Stomach; Structure; Sulfhydryl Compounds; Swimming; System; Tertiary Protein Structure; Testing; Therapeutic Uses; Tissues; Training; Ulcerative Colitis; Universities; Virulent; Work; Zebrafish; Zinc; antimicrobial; bacterial community; blind; career development; cell motility; chronic infection; commensal bacteria; diguanylate cyclase; drug discovery; experience; experimental study; gut colonization; imaging genetics; in vivo; insight; malignant stomach neoplasm; microbial; mouse model; neutrophil; novel; oxidation; pathogen; pathogenic bacteria; persistent bacteria; prevent; receptor; response; sensor; zinc-binding protein

PROJECT SUMMARY/ABSTRACT A large body of research has elucidated the role of bleach (HOCl) as a potent antimicrobial produced by the immune system through neutrophil myeloperoxidase, but new findings have provided intriguing instances in which this paradigm is challenged, and some important human bacterial pathogens such as Salmonella Typhimurium and Helicobacter pylori have been shown to actually be attracted to inflamed tissue—where HOCl can reach millimolar concentrations—and can exploit host inflammation processes to colonize and establish persistent infections. The molecular basis for how these bacteria can use motility and chemotaxis to respond to HOCl and reaction products is mostly unknown, and represents an important new direction for infectious disease research with the potential to provide many insights into how pathogenic and commensal bacteria colonize and persist in animal hosts to cause disease. The broad and long-term objective of this project is to learn how host-associated bacteria navigate the inflammation and redox landscape of the gut, which has implications for many human infectious diseases, especially those involving bacterial-promoted chronic inflammation such as stomach cancer, ulcerative colitis, and inflammatory bowel diseases. The key focus of this project is to advance understanding of how host-associated bacteria sense and respond to inflammation by investigating a novel bleach-sensing regulatory module referred to as chemoreceptor zinc-binding (CZB) domains that are conserved broadly in commensal and pathogenic bacteria. Specific Aim 1 will use a reductionist in vitro approach to test if CZB domains function through a conserved mechanism by analyzing residue conformation patterns and determining the reactivity with HOCl of representative CZB proteins from H. pylori, S. Typhimurium, and E. coli. Specific Aim 2 will perform the first tests of the biological roles of CZB domains in bacterial infections with a novel ELISA chemotaxis assay and infections in zebrafish and mouse model organisms. Important for the Career Development of Dr. Arden Perkins, this project will provide him comprehensive new training in using animal models, which he has never done, as well as expertise in microscopy and live imaging, and genetic engineering of bacteria. This training will build on Dr. Perkins’ prior experience in protein crystallography, drug discovery, and redox biology to make him a competent investigator at the interface of in vitro and in vivo work, and enable him to pursue investigations into the functions of key proteins involved in bacterial infections at the molecular and biological levels. Dr. Perkins will be trained at University of Oregon in the zebrafish system, a high throughput model in which he will study bacterial dynamics and responses to neutrophils in situ, and collaborators Dr. Manuel Amieva at Stanford and Dr. Andreas Baumler at UC Davis will provide expert guidance and support for extending these studies to mouse models of infection of H. pylori and S. Typhimurium, respectively.

项目概要/摘要 大量研究已经阐明了漂白剂 (HOCl) 作为一种强效抗菌剂的作用，该抗菌剂是由漂白剂产生的 免疫系统通过中性粒细胞髓过氧化物酶，但新的发现提供了有趣的例子 这种范式受到挑战，一些重要的人类细菌病原体，如沙门氏菌 鼠伤寒菌和幽门螺杆菌已被证明实际上会被发炎组织所吸引，其中次氯酸 可以达到毫摩尔浓度，并且可以利用宿主炎症过程来定植和建立 持续感染。这些细菌如何利用运动性和趋化性来响应的分子基础 HOCl和反应产物大多是未知的，代表了传染病的一个重要新方向 研究有可能为致病菌和共生菌如何定殖和提供许多见解 持续存在于动物宿主体内引起疾病。该项目的广泛和长期目标是了解如何 宿主相关细菌在肠道炎症和氧化还原环境中导航，这对 许多人类传染病，特别是那些涉及细菌引发的慢性炎症的疾病，例如 胃癌、溃疡性结肠炎和炎症性肠病。该项目的重点是推进 通过研究一种新的方法来了解宿主相关细菌如何感知和响应炎症 漂白剂感应调节模块，称为保守的化学感受器锌结合 (CZB) 结构域 广泛存在于共生菌和致病菌中。具体目标 1 将使用还原论体外方法来测试是否 CZB 结构域通过分析残基构象模式和保守机制发挥作用 确定来自幽门螺杆菌、鼠伤寒沙门氏菌和大肠杆菌的代表性 CZB 蛋白与 HOCl 的反应性。 具体目标 2 将首次测试 CZB 结构域在细菌感染中的生物学作用 斑马鱼和小鼠模型生物体中的新型 ELISA 趋化性测定和感染。 该项目对于 Arden Perkins 博士的职业发展非常重要，将为他提供全面的新知识 他从未接受过使用动物模型的培训，以及显微镜和实时成像方面的专业知识， 和细菌的基因工程。该培训将以 Perkins 博士之前在蛋白质方面的经验为基础 晶体学、药物发现和氧化还原生物学使他成为一名称职的研究人员 体外和体内工作，使他能够研究参与的关键蛋白质的功能 分子和生物水平上的细菌感染。 Perkins 博士将在俄勒冈大学接受培训 斑马鱼系统，一个高通量模型，他将在其中研究细菌动力学和对细菌的反应 原位中性粒细胞，斯坦福大学的 Manuel Amieva 博士和加州大学戴维斯分校的 Andreas Baumler 博士的合作者将 为将这些研究扩展到幽门螺杆菌感染的小鼠模型提供专家指导和支持， 分别是鼠伤寒沙门氏菌。