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

• 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
• 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' 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

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.

项目摘要 细菌对宿主细胞的附着是致病的关键步骤。因此，预防细菌性 附着于宿主细胞是阻止疾病进展的理想目标。严重缺乏知识， 伯克霍尔德菌属的附着机制极大地抑制了我们开发有效治疗的能力 战略布局洋葱伯克霍尔德氏菌复合体（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是一种无法治愈的危及生命的疾病， 难在美国大约有30，000人患有CF，全世界有70，000多人。 Bcc也是一组重要的病原体，可导致其他免疫抑制患者的医院感染。 几次感染暴发所突出的个人。 我们在类鼻疽伯克霍尔德菌中发现了一种新的表面附着蛋白，这是一项重要的研究发现 （Sap 1Bp），一个以前没有特征的假设蛋白，提供了一个机会，研究一个新的 而且似乎是许多伯克霍尔德氏菌物种所利用的通用附着机制。Sap 1Bp在功能上 在许多伯克霍尔德菌属物种中保守，包括来自Bcc临床相关成员的Sap 1（Sap 1Bcc）。 BCC采用的依恋机制很多，而且很复杂。然而，没有相关的 到目前为止，已经发现了来自宿主细胞的受体伴侣，这在免疫学领域留下了重大的知识空白。 理解BCC中的连接机制。我们发现Sap 1Bcc对Bcc有显著的贡献 在多种动物模型中，Bcc细胞粘附在宿主细胞上，是完整的Bcc发病机制所必需的。此外，委员会认为， 我们发现Sap 1宿主细胞受体是糖蛋白非转移性黑素瘤蛋白B（GPNMB）， 它与各种癌症和阿尔茨海默病有关，揭示了一种新颖独特的相互作用， 从未被任何细菌病原体利用来附着和侵入宿主细胞。 在本申请中，我们提出探索这种重要的表面附着蛋白的机制 Sap 1Bcc在体外与其宿主细胞受体GPNMB相互作用以及这种相互作用在体内的重要性 发病机制目的1A将在分子水平上表征Sap 1Bcc和GPNMB的相互作用， 它们的相互作用亲和力和确定关键残基的附着功能，这是至关重要的，为未来的研究， 毒力机制。目的1B旨在从功能上表征GPNMB在Sap 1Bcc依赖性细胞凋亡中的作用。 BCC附着于GPNMB敲除和过表达细胞。目的1C将研究GPNMB在 Bcc小鼠感染，以确定新毒力因子Sap 1Bcc与其宿主细胞之间的相互作用 GPNMB受体直接导致疾病。新发现的Sap 1Bcc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， BCC感染的治疗效果。