Regulation and impact of lipid A modification in the pathogenesis of Porphyromonas gingivalis

脂质A修饰在牙龈卟啉单胞菌发病机制中的调控及影响

• 批准号: 10502017
• 负责人: Sumita Jain
• 金额: $ 36.93万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-09 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10502017
• 关键词: Anaerobic Bacteria; Animal Model; Cell Wall; Cellular Structures; Characteristics; Chronic; Clinical; Data; Dental; Dental Plaque; Development; Diagnostic; Disease; Environmental Risk Factor; Enzymes; Excision; Exhibits; Future; Gene Expression; Gene-Modified; Genes; Gingivitis; Glucosamine; Gram-Negative Bacteria; Growth; Health; Human; Immune; Immune Evasion; In Vitro; Infection; Infection Control; Inflammation; Inflammatory; Innate Immune Response; Knowledge; Lead; Link; Lipid A; Longitudinal Studies; Mediating; Membrane; Modification; Molecular; Natural Immunity; Pathogenesis; Peptide Hydrolases; Periodontal Diseases; Periodontitis; Phenotype; Phosphoric Monoester Hydrolases; Play; Porphyromonas gingivalis; Positioning Attribute; Prevalence; Process; Production; Property; Proteins; Regulation; Regulator Genes; Reporting; Role; Sampling; Site; Structure; System; TLR4 gene; Testing; Therapeutic; Transcription Initiation Site; Variant; Vertebral column; Vesicle; Virulence; Virulence Factors; Work; diagnostic tool; dysbiosis; fitness; gingipain; immunoregulation; in vivo; inorganic phosphate; microbial; mutant; novel; pathogen; receptor; response; tool

Porphyromonas gingivalis is a sub-gingival Gram-negative bacterium that is closely associated with periodontitis, a chronic inflammatory disorder. Found in low numbers in healthy sites, its prevalence increases during disease, indicating it is well equipped to survive hostile inflammatory conditions. Animal models have demonstrated that P. gingivalis infection causes microbial dysbiosis in sub-gingival plaque with an ensuing increase in inflammation, which are the hallmarks of periodontal disease, marking it as a keystone pathogen. P. gingivalis evades the powerful innate immune response mediated by the receptor TLR4 by modifying its lipid A structure and has the unusual ability to elicit copious amounts of outer membrane vesicles (OMVs) armed with select virulence factors such as innate host protein destroying proteases. We have identified the crucial lipid A modification genes which are responsible for lipid A structural changes that elicit TLR4 evasion, and, additionally, contribute to OMV formation. These genes are a lipid A deacylase gene encoded by PGN_1123, and PG1773 and PG1587, which encode lipid A C1- and C4'-phosphatases respectively. In Preliminary Data, we demonstrate that all three of these genes are expressed higher in vivo in human plaque samples than in vitro and also exhibit higher expression in diseased sites than in health. However, nothing is known concerning how these genes are regulated in response to differing environmental conditions. We next demonstrate that lipid A phosphatase mutants have opposing effects on vesicle formation, suggesting regulation of PG1587 and PG1773 modulates the amount of OMVs produced. Therefore, in this application the following hypothesis will be tested: “P. gingivalis modifies its lipid A structure in response to local environmental conditions and this contributes both to its ability to survive in vivo and secrete virulence factors.” This hypothesis will be tested by the following three Specific Aims: Specific Aim 1. Characterize regulation of PGN_1123, PG1587 and PG1773 lipid A modification genes: Specific Aim 2. Determine the contribution of P. gingivalis lipid A structure and associated outer membrane molecules on OMV formation. Specific Aim 3. Comprehensive analysis of lipid A phosphatase gene expression in vivo. This work will significantly advance our knowledge of P. gingivalis pathogenesis in vivo. Future studies will include characterization of factors required for vesiculation. Overall, these studies will enable the development of diagnostic and therapeutic tools to control infection of this keystone pathogen.

牙龈卟啉单胞菌是一种亚生物的革兰氏阴性细菌，与之紧密相关。 牙周炎是一种慢性炎症障碍。 在疾病期间，表明它可以在敌对的炎症状态下运行 证明牙龈感染引起的微生物失调 增加炎症，这是牙周疾病的标志，将其标记为基石病原体。 牙龈疟原虫通过修饰其脂质来逃避由受体TLR4介导的强大的INATE免疫反应 一种结构，并且具有引起大量大量外膜囊泡（OMV）武装的异常能力 与先天宿主蛋白等选择的病毒因素，我们已经确定了至关重要的蛋白酶。 脂质的一个修饰基因，负责脂质A结构的变化会导致TLR4逃避，并且 另外，有助于OMV形成。 以及PG1773和PG1587，它们对脂质A C1和C4'-phosphatasses进行了敏感。 在初步数据中，我们证明了三个颗粒中的三个在人的体内表达更高 斑块样品比体外的样品，并且在患病部位的表达也高于健康。 响应不同的环境条件，对如何进行有关如何进行污水的人众所周知。 接下来，我们证明脂质A磷酸酶毒素对囊泡的形成有相反的作用，这表明 PG1587和PG1773的调节调节产生的AMV。 因此，在应用程序中，将测试以下假设 响应当地的环境，这两者都可以在体内生存和 分泌的病毒因素。 表征PGN_1123，PG1587和PG1773脂质的调节基因：特定AM 2。 确定牙龈疟原虫脂质A结构和相关外膜分子对OMV的贡献 组成。 这显着提高了我们对未来研究的牙龈疟原虫发病机理的了解 包括表征vescription所需的因素。 控制这种基石病原体感染的诊断和治疗工具。