Analysis of newly identified adhesin used by pathogenic Gram-negative bacteria

致病性革兰氏阴性菌使用的新发现的粘附素的分析

• 批准号: 8304009
• 负责人: Kim Orth
• 金额: $ 19.87万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8304009
• 关键词: Actins; Adhesions; Animals; Attenuated; Bacteria; Bacterial Adhesins; Bacterial Infections; Bacterial Typing; Binding; Biochemical; Biological; Cell Adhesion Molecules; Cell-Matrix Junction; Cells; Consumption; Cytoskeleton; Fibronectin Receptors; Fibronectins; Foundations; Future; Gastroenteritis; Genes; Goals; Gram-Negative Bacteria; Hemolysin; Infection; Investigation; Lead; Lipids; Mediating; Membrane Proteins; Phosphatidic Acid; Production; Proteins; Receptor Cell; Recombinants; Role; Seafood; Signal Pathway; Signal Transduction; Staging; Surface; Type III Secretion System Pathway; Vibrio parahaemolyticus; cytotoxicity; inhibitor/antagonist; insight; interest; novel; pathogen; protein protein interaction; receptor; research study

DESCRIPTION (provided by applicant): The aim of this proposal is to characterize a newly multivalent adhesion molecule (MAM7) found in the majority of Gram-negative pathogenic animal bacteria. We propose that MAM7 is involved in the initial contact of bacterial pathogens with host cells. As a representative for this type of molecule, we will use the MAM7 protein from Vibrio parahaemolyticus, an emerging pathogen that causes gastroenteritis through consumption of raw or undercooked seafood, to study the multivalent binding to host cells. We observe MAM7 dependent changes in the actin cytoskeleton in host cells. We predict that binding of MAM7 will trigger the production of more adhesion factors in the bacterial pathogens. Thus as one of our aims, we would like to uncover the signaling machinery activated in the bacteria and the host cell upon binding of MAM7. In another aim, we would like to understand the biochemical interaction of MAM7 with its two host cell receptors, fibronectin and phosphatidic acid. This information will be extremely valuable for future studies focused on MAM7 inhibitors. Finally, we observe that binding of non-pathogenic bacteria expressing MAM7 (BL21-MAM7) to host cells ameliorates cytotoxicity of Gram-negative pathogens expressing MAM7. We are interested in determining how broadly MAM7 provides a competitive advantage over other types of bacterial pathogens that do not express MAM7 but other types of adhesins. Together, these experiments will allow us to characterize the newly identified multivalent adhesion molecule MAM7 and will help to elucidate its value as a competitive inhibitor for a wide variety of bacterial pathogens. PUBLIC HEALTH RELEVANCE: The aim of this proposal is to characterize a newly identified multivalent adhesion molecule (MAM7) that mediates the initial interaction between the eukaryotic host and the bacterial pathogen. We will use the MAM7 from Vibrio parahaemolyticus, an emerging pathogen that causes gastroenteritis through consumption of raw or undercooked sea food, to study the host/pathogen crosstalk upon binding of MAM7 to the previously identified host cell receptors, determine the biochemical interaction of host receptors with MAM7 and elucidate the value of MAM7 in augmenting bacterial infections.

描述（由申请人提供）：本提案的目的是表征在大多数革兰氏阴性致病动物细菌中发现的新多价粘附分子（MAM7）。我们认为 MAM7 参与细菌病原体与宿主细胞的初始接触。作为此类分子的代表，我们将使用来自副溶血性弧菌（一种通过食用生的或未煮熟的海鲜引起胃肠炎的新兴病原体）的 MAM7 蛋白来研究与宿主细胞的多价结合。我们观察到宿主细胞中肌动蛋白细胞骨架的 MAM7 依赖性变化。我们预测 MAM7 的结合将触发细菌病原体产生更多粘附因子。因此，作为我们的目标之一，我们希望揭示 MAM7 结合后在细菌和宿主细胞中激活的信号机制。另一个目标是，我们希望了解 MAM7 与其两种宿主细胞受体（纤连蛋白和磷脂酸）的生化相互作用。这些信息对于未来针对 MAM7 抑制剂的研究非常有价值。最后，我们观察到表达 MAM7 (BL21-MAM7) 的非病原菌与宿主细胞的结合改善了表达 MAM7 的革兰氏阴性病原体的细胞毒性。我们感兴趣的是确定 MAM7 相对于不表达 MAM7 但表达其他类型粘附素的其他类型细菌病原体具有多大的竞争优势。总之，这些实验将使我们能够表征新鉴定的多价粘附分子 MAM7，并将有助于阐明其作为多种细菌病原体的竞争性抑制剂的价值。 公共健康相关性：该提案的目的是表征新鉴定的多价粘附分子（MAM7），该分子介导真核宿主和细菌病原体之间的初始相互作用。我们将使用来自副溶血性弧菌（一种通过食用生的或未煮熟的海鲜引起胃肠炎的新兴病原体）的 MAM7，研究 MAM7 与先前识别的宿主细胞受体结合后的宿主/病原体串扰，确定宿主受体的生化相互作用与 MAM7 并阐明 MAM7 在增强细菌感染方面的价值。