Small host GTPases: Direct targets of Vibrio vulnificus MARTX toxin effectors

小宿主 GTP 酶：创伤弧菌 MARTX 毒素效应子的直接靶标

• 批准号: 10457416
• 负责人: Alfa Herrera
• 金额: $ 9.85万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10457416
• 关键词: ADP-Ribosylation Factors; Affect; Amputation; Antibiotics; Apoptosis; Bacteria; Bacterial Toxins; Binding; Biochemical; Biological Assay; Biology; Bolus Infusion; C-terminal; Caspase; Cell physiology; Cells; Cessation of life; Collaborations; Communities; Consumption; Cytoplasm; Data; Defect; Development; Development Plans; Disease; Disease Progression; Elderly; Environment; Epithelial Cells; Fellowship; Florida; Genes; Geographic Distribution; Goals; Golgi Apparatus; Gram-Negative Bacteria; Guanosine Triphosphate Phosphohydrolases; Hour; Immunocompromised Host; Immunofluorescence Microscopy; Immunology; Incidence; Individual; Induction of Apoptosis; Infection; Inhibition of Cell Proliferation; Intestines; Knowledge; Life; Link; Liposomes; Location; Maryland; Measures; Membrane; Mentors; Microbiology; Microscopy; Mitochondria; Modeling; Modification; Monomeric GTP-Binding Proteins; Morbidity - disease rate; Mutate; N-terminal; Pathogenesis; Patients; Persons; Proteins; Recombinant Proteins; Research; Research Personnel; Research Project Grants; Research Proposals; Resources; Scientist; Seafood; Seawater; Sepsis; Severities; Site; Solid; Specificity; Structure; Symptoms; System; Techniques; Testing; Therapeutic; Tissues; Toxic effect; Toxin; Training; Vibrio; Vibrio vulnificus; Virulence Factors; Water; Work; Wound Infection; cell killing; climate change; cytotoxic; cytotoxicity; enteric infection; extracellular; gastrointestinal infection; host-microbe interactions; improved; in vivo; mortality; mouse model; novel; novel strategies; pathogen; phosphatidylinositol 5-phosphate; protein function; research and development; skills; structural biology; therapy development

Project Summary/Abstract Gastrointestinal and wound infections caused by the Gram-negative bacterium Vibrio vulnificus (Vv) can be exceptionally life-threatening resulting in death in approximately 50% of cases. These infections progress within days and must be identified and treated quickly to decrease mortality and morbidity. While antibiotics are used to treat Vv infections, they are often ineffective as the disease progresses rapidly, especially in immunocompromised individuals. This disease is of particular concern now as the incidence of the disease is increasing due to climate change. The Multifunctional Autoprocessing Repeats in Toxin (MARTX) toxin is a large protein toxin that is secreted by Vv and is essential to cause infections. The MARTX toxin functions to deliver up to five different toxic effectors as a single bolus directly into the eukaryotic host cytoplasm. There are ten known unique effectors, and each is capable of causing cytotoxic effects. Determining the mechanism by which the effectors encoded within the MARTX toxin function will reveal a novel mechanisms related to bacterial toxin function that could impact our understanding of host-microbe interactions across many diverse systems. The Makes Caterpillars Floppy-like (MCF) toxin is the most common Vv MARTX effector. MCF is linked to Golgi dispersion, inhibition of cell proliferation, and apoptosis. In preliminary studies, MCF is observed to be stimulated to autoprocess via binding to ADP-ribosylation factors resulting in its absolute release as an individual effector domain within the host cell and activation. However, how MCF functions within the eukaryotic host once individually released and activated that results in its toxicity is unclear. The goal of this proposal is to investigate the hypothesis that, once activated, MCF moves on to bind and target another class of small GTPases, Rabs, resulting in a disruption of proper cell functions. To test this hypothesis, we will determine: 1) Which subset of Rabs are the target of MCF; 2) How MCF gains access to these Rabs; 3) How this interaction alters proper Rab functioning and localization; 4) The manner in which these two proteins interact; and 5) The function of the different domains of MCF. In addition, these studies will involve training to utilize novel techniques and concepts. The results from this work have the potential to develop into several independent research projects. The proposed fellowship will involve collaborations, which are facilitated and encouraged in the Department of Microbiology-Immunology at Northwestern.

项目概要/摘要 由革兰氏阴性菌创伤弧菌 (Vv) 引起的胃肠道和伤口感染可 异常危及生命，导致约 50% 的病例死亡。这些感染在 天，必须迅速识别和治疗，以降低死亡率和发病率。当使用抗生素时 治疗 Vv 感染时，随着疾病迅速进展，它们通常无效，尤其是在 免疫功能低下的个体。由于该病的发病率很高，因此现在特别关注该病 由于气候变化而增加。毒素中的多功能自动处理重复序列 (MARTX) 毒素是一种大型毒素 由 Vv 分泌的蛋白质毒素，对于引起感染至关重要。 MARTX 毒素的作用是释放 将五种不同的毒性效应物作为单次推注直接进入真核宿主细胞质。已知的有十个 独特的效应器，每个都能够引起细胞毒性作用。确定机制 MARTX毒素功能内编码的效应器将揭示与细菌毒素相关的新机制 可能会影响我们对许多不同系统中宿主-微生物相互作用的理解。这 毛毛虫软盘样 (MCF) 毒素是最常见的 Vv MARTX 效应物。 MCF 与高尔基体相连 分散、抑制细胞增殖和凋亡。在初步研究中，观察到 MCF 受到刺激 通过与 ADP-核糖基化因子结合进行自动处理，导致其作为个体效应器的绝对释放 宿主细胞内的结构域和激活。然而，MCF 在真核宿主内如何发挥作用？ 单独释放和激活导致其毒性尚不清楚。该提案的目的是调查 假设一旦激活，MCF 就会继续结合并靶向另一类小 GTP 酶、Rab、 导致正常细胞功能的破坏。为了检验这个假设，我们将确定：1）哪个子集 兔子是MCF的目标； 2) MCF 如何获得这些 Rab 的访问权限； 3) 这种相互作用如何改变适当的 Rab 功能和本地化； 4）这两种蛋白质相互作用的方式； 5) 的功能 MCF 的不同域。此外，这些研究将涉及利用新技术和概念的培训。 这项工作的结果有可能发展成几个独立的研究项目。这 拟议的研究金将涉及合作，该部将促进和鼓励合作 西北大学微生物学-免疫学。