Phenotypic, transcriptomic and pathogenic study of the first cultivated TM7 strain

第一个培养的TM7菌株的表型、转录组和致病性研究

• 批准号: 9399092
• 负责人: Batbileg Bor
• 金额: $ 0.07万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-12-17 至 2017-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9399092
• 关键词: Actinomyces odontolyticus; Address; Adhesions; Affect; Bacteria; Biochemical; Biological Models; Candidate Disease Gene; Cell Death; Cells; Chromosome Mapping; Coculture Techniques; Disease; Epithelial; Etiology; Gene Expression; Gene Expression Profiling; Gene Expression Regulation; Genes; Genetic; Goals; Growth; Health; Human; Human Microbiome; Human body; Immune; Immune response; Individual; Inflammatory; Inflammatory Bowel Diseases; Investigation; Knock-out; Knowledge; Lead; Link; Measures; Metabolic; Methods; Microbe; Microscopy; Molecular; Molecular Profiling; Monitor; Morphology; Mouth Diseases; Oral; Oral cavity; Parasites; Pathogenesis; Pathogenicity; Pathway interactions; Periodontal Diseases; Periodontitis; Phenotype; Physiological; Plasmids; Production; Recombinant DNA; Role; Sampling; Site; Surface; System; TNF gene; Testing; Ulcer; Virulence; base; chemokine; genetic analysis; in vivo; insight; macrophage; member; microbiota; novel; oral bacteria; prevent; public health relevance; screening; therapeutic development; tissue culture; tool; tool development; transcriptomics

 DESCRIPTION (provided by applicant): The overarching objective of this application is to achieve a detailed understanding of the first cultivated TM7 phylotype from the human oral cavity and explore its pathogenic potential. Since the initiation of the Human Microbiome Project, a tremendous diversity of bacteria has been discovered in the human body, many of which have no cultured representatives. Studying these supposedly uncultivable bacteria presents a major challenge to the field. Members of the applicant division TM7 phylum are the most prevalent yet elusive of these bacteria. TM7 has been found in various human body sites and environmental samples, and also been linked to human mucosal diseases, particularly severe and ulcerative periodontitis, vaginosis, and inflammatory bowel disease. Therefore, the impact of this study is twofold: it will increase our knowledge of uncultivable bacteria and will illuminate the pathogenic potential of TM7 members. Using novel cultivation methods, our lab recently cultured the first TM7 member (TM7x) attached to the surface of a previously uncultivated Actinomyces odontolyticus strain (XH001) from the oral cavity. TM7x was not able to grow on its own, suggesting that the presence of XH001 is crucial to TM7x's survival. In contrast, XH001 had accelerated cell death and sporulation in presence of TM7x. This type of epibiotic parasite interaction is completely novel and has never been observed in oral microbiota. Furthermore, TM7x, when associated with XH001, can prevent the induction of TNFa gene expression by macrophages, suggesting its possible role in modulating the immune response. Yet many questions remain unanswered: Why does TM7x need XH001? Does TM7x adhere to the surfaces of other oral bacteria? What are their individual and combined pathogenic potentials? Based on our initial findings, I hypothesize that physical and/or metabolic interactions between TM7x and XH001 are crucial for the growth of TM7x and have a great impact on their pathogenicity. Uncovering this interaction at the molecular level will elucidate th impact of TM7x on human health and disease. To explore these hypotheses, I will carry out four interconnected but independent aims: (1) I will first thoroughly characterize the morphological and physiological changes of TM7x and XH001 during different stages of co-culture growth. (2) I will next analyze the global gene expression of each growth stage to uncover the underlying genetics of the observed morphological changes. (3) I will manipulate gene expression of TM7x or XH001 to further evaluate the interaction between TM7x and XH001. (4) Once I understand the interaction between TM7x and XH001, I will apply this knowledge to study the pathogenic potential of TM7x in association with XH001.

 描述（由申请人提供）：本申请的总体目标是详细了解来自人类口腔的第一个培养的TM 7大肠杆菌类型，并探索其致病潜力。自人类微生物组计划启动以来，在人体内发现了大量多样性的细菌，其中许多细菌没有培养的代表。研究这些被认为是不可培养的细菌对该领域提出了重大挑战。申请人TM 7门的成员是这些细菌中最普遍但最难以捉摸的。TM 7已在各种人体部位和环境样品中发现，并且还与人类粘膜疾病，特别是严重和溃疡性牙周炎、阴道病和炎性肠病有关。因此，这项研究的影响是双重的：它将增加我们对不可培养细菌的了解，并将阐明TM 7成员的致病潜力。 利用新的培养方法，我们的实验室最近培养了第一个TM 7成员（TM 7 x）附着在以前未培养的溶牙放线菌菌株（XH 001）的表面。TM 7 x不能自己生长，这表明XH 001的存在对TM 7 x的存活至关重要。相比之下，XH 001在TM 7 x存在下具有加速的细胞死亡和孢子形成。这种类型的表生寄生虫相互作用是完全新颖的，从未在口腔微生物群中观察到。此外，当与XH 001结合时，TM 7 x可以阻止巨噬细胞诱导TNF α基因表达，表明其在调节免疫应答中的可能作用。然而，许多问题仍然没有答案：为什么TM 7 x需要XH 001？TM 7 x是否会粘附在其他口腔细菌的表面？它们各自和联合的致病潜力是什么？基于我们的初步研究结果，我推测TM 7 x和XH 001之间的物理和/或代谢相互作用对TM 7 x的生长至关重要，并对它们的致病性有很大的影响。在分子水平上揭示这种相互作用将阐明TM 7 x对人类健康和疾病的影响。 为了探索这些假设，我将进行四个相互关联但独立的目标：（1）我将首先彻底表征TM 7 x和XH 001在共培养生长的不同阶段的形态和生理变化。(2)接下来，我将分析每个生长阶段的整体基因表达，以揭示观察到的形态变化的潜在遗传学。(3)我将操纵TM 7 x或XH 001的基因表达，以进一步评估TM 7 x和XH 001之间的相互作用。(4)一旦我了解了TM 7 x和XH 001之间的相互作用，我将应用这些知识研究TM 7 x与XH 001相关的致病潜力。