A novel attachment mechanism for Burkholderia cepacia complex

洋葱伯克霍尔德菌复合体的新型附着机制

基本信息

批准号：
10649379
负责人：
Tung T Hoang
金额：
$ 21.83万
依托单位：
UNIVERSITY OF HAWAII AT MANOA
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-02-15 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10649379
关键词：
Acute Affinity Alzheimer&apos s Disease Animal Model Antibiotic Resistance Bacteria Bacterial Attachment Site Binding Burkholderia Burkholderia Infections Burkholderia cepacia Burkholderia cepacia complex Burkholderia pseudomallei Cell Culture Techniques Cell Line Cell Surface Proteins Cell Surface Receptors Cell surface Cell-Matrix Junction Cells Clinical Complex Cystic Fibrosis Disease Disease Outbreaks Disease Progression Drug Targeting Enzyme-Linked Immunosorbent Assay Future Glycoproteins Goals Gram-Negative Bacteria Homologous Gene Hypothetical Protein In Vitro Inbred BALB C Mice Individual Infection Invaded Knock-out Knowledge Life Lung infections Malignant Neoplasms Membrane Proteins Modeling Molecular Mus Nonmetastatic Nosocomial Infections Pathogenesis Persons Pneumonia Prevention Process Prokaryotic Cells Proteins Public Health Receptor Cell Research Role SH2D1A gene Surface Syndrome Technology Therapeutic Treatment outcome United States Vaccines Virulence Virulence Factors Virus antimicrobial peptide chronic infection clinically relevant cystic fibrosis infection cystic fibrosis patients effective therapy emerging pathogen immunosuppressed improved in vivo melanoma member mortality novel novel vaccines overexpression pathogen pathogenic bacteria prevent protein B receptor transcriptome treatment strategy vaccine development

项目摘要

PROJECT SUMMARY Bacterial attachment to host cells is a critical step for pathogenesis. Thus, the prevention of bacterial attachment to host cells is an ideal target to halt disease progression. A severe lack of knowledge of the attachment mechanism of Burkholderia species greatly inhibits our ability to develop effective treatment strategies. Burkholderia cepacia complex (Bcc), consisting of more than 20 species of Gram-negative bacteria, poses a major threat to public health. Bcc causes severe opportunistic lung infections in cystic fibrosis (CF) patients worldwide. CF is a life-threatening condition with no cure and treatment of CF-related infections is difficult. There are about 30,000 people with CF in the United States and more than 70,000 people worldwide. Bcc is also a group of significant pathogens leading to nosocomial infections in other immunosuppressed individuals highlighted by several outbreaks of infection. Our significant research discovery of a novel surface attachment protein from Burkholderia pseudomallei (Sap1Bp), a previously uncharacterized hypothetical protein, has provided an opportunity to investigate a new and, seemingly, universal attachment mechanism exploited by many Burkholderia species. Sap1Bp is functionally conserved across many Burkholderia species, including Sap1 from clinically relevant members of Bcc (Sap1Bcc). There are many attachment mechanisms employed by Bcc and they are complex. However, no associated receptor partners from host cells have been discovered to date, leaving significant knowledge gaps in the understanding of attachment mechanisms in the Bcc. We found that Sap1Bcc contributes significantly to Bcc attachment to the host cells and is required for complete Bcc pathogenesis in multiple animal models. Moreover, we discovered the Sap1 host-cell receptor to be the glycoprotein non-metastatic melanoma protein B (GPNMB), which is associated with various cancers and Alzheimer's disease, revealing a novel and unique interaction that has never been exploited by any bacterial pathogens to attach and invade host cells. In this application, we proposed to explore the mechanisms of this important surface attachment protein Sap1Bcc to interact with its host-cell receptor GPNMB in vitro and the importance of this interaction for in vivo pathogenesis. Aim 1A will characterize Sap1Bcc and GPNMB interaction at the molecular level by determining their interaction affinity and defining the key residues for attachment function, which is critical for future study of its virulence mechanism. Aim 1B seeks to functionally characterize the roles of GPNMB in Sap1Bcc-dependent Bcc attachment to GPNMB knockout and overexpression cells. Aim 1C will investigate the role of GPNMB during Bcc murine infection to determine if the interaction between the novel virulence factor Sap1Bcc and its host cell receptor GPNMB directly contributes to disease. Detailed characterizations of this newly discovered Sap1Bcc /GPNMB interaction could provide potential drug-target and alternative therapeutic strategies toward better treatment outcomes of Bcc infection.

项目概要细菌附着于宿主细胞是发病机制的关键步骤。因此，预防细菌与宿主细胞的附着是阻止疾病进展的理想目标。严重缺乏相关知识伯克霍尔德杆菌属物种的附着机制极大地抑制了我们开发有效治疗方法的能力策略。洋葱伯克霍尔德菌复合体（Bcc），由20多种革兰氏阴性菌组成，对公众健康构成重大威胁。 Bcc 导致囊性纤维化 (CF) 中严重的机会性肺部感染全世界的患者。 CF 是一种危及生命的疾病，无法治愈，CF 相关感染的治疗方法是难的。美国约有 30,000 名 CF 患者，全球有 70,000 多人。 Bcc 也是一组导致其他免疫抑制患者院内感染的重要病原体多次爆发感染的个人。我们对类鼻疽伯克霍尔德氏菌的新型表面附着蛋白的重大研究发现 (Sap1Bp)，一种以前未表征的假设蛋白质，提供了研究一种新的机会而且，似乎许多伯克霍尔德杆菌物种都利用了通用的附着机制。 Sap1Bp 在功能上在许多伯克霍尔德杆菌属物种中保守，包括来自 Bcc 临床相关成员的 Sap1 (Sap1Bcc)。 Bcc 采用多种附加机制，而且很复杂。然而，没有相关联迄今为止，已经发现了来自宿主细胞的受体伴侣，在这方面留下了巨大的知识空白了解密件抄送中的附件机制。我们发现 Sap1Bcc 对 Bcc 有显着贡献附着于宿主细胞，是多种动物模型中完整 Bcc 发病机制所必需的。而且，我们发现 Sap1 宿主细胞受体是糖蛋白非转移性黑色素瘤蛋白 B (GPNMB)，它与多种癌症和阿尔茨海默病有关，揭示了一种新颖而独特的相互作用，从未被任何细菌病原体利用来附着和侵入宿主细胞。在此应用中，我们建议探索这种重要的表面附着蛋白的机制 Sap1Bcc 在体外与其宿主细胞受体 GPNMB 相互作用以及这种相互作用对于体内的重要性发病。目标 1A 将通过确定在分子水平上表征 Sap1Bcc 和 GPNMB 相互作用它们的相互作用亲和力并定义附着功能的关键残基，这对于未来的研究至关重要其毒力机制。目标 1B 旨在从功能上描述 GPNMB 在 Sap1Bcc 依赖性中的作用 Bcc 附着至 GPNMB 敲除和过表达细胞。目标 1C 将调查 GPNMB 在 Bcc 小鼠感染以确定新型毒力因子 Sap1Bcc 与其宿主细胞之间是否存在相互作用受体 GPNMB 直接导致疾病。新发现的 Sap1Bcc 的详细特征 /GPNMB 相互作用可以提供潜在的药物靶点和替代治疗策略，以实现更好的效果 Bcc 感染的治疗结果。