The interplay between nutrient availability and secondary bile acid metabolism in commensal Clostridia mediates colonization resistance against C. difficile

共生梭状芽胞杆菌中营养可用性和次级胆汁酸代谢之间的相互作用介导对艰难梭菌的定植抵抗

• 批准号: 10622031
• 负责人: Casey Michelle Theriot
• 金额: $ 38万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-24 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10622031
• 关键词: Affect; Amino Acids; Animal Model; Antibiotics; Area; Bacterial Physiology; Basic Science; Bile Acids; Biochemistry; Biological Process; Biomass; Clostridium difficile; Complex; Data; Development; Diet; Disease; Environment; Foundations; Germ-Free; Goals; Gram-Positive Bacteria; Growth; Health; Human; Immune response; In Vitro; Indigenous; Individual; Infection; Intelligence; Intestines; Knowledge; Laboratories; Mediating; Metabolism; Methods; Microbe; Mission; National Institute of General Medical Sciences; Nutrient; Nutrient availability; Prevention; Production; Protein Engineering; Proteins; Proteomics; Public Health; Reproducibility; Reproduction spores; Research; Role; Shapes; Structure; Techniques; Technology; Therapeutic; Therapeutic Intervention; United States National Institutes of Health; bacterial genetics; bile acid metabolism; colonization resistance; combinatorial; design; disease diagnosis; gut microbiome; gut microbiota; host-microbe interactions; improved; in vivo; metabolome; metabolomics; microbial; microbial community; microbiome; microbiome research; model organism; mouse model; novel; pathogen; prevent; therapeutic development; transcriptomics

Project Summary/Abstract In the Theriot laboratory we apply cutting-edge technology and high-throughput methods to analyze the gut microbiome and metabolome using a range of experimental techniques and animal models. We leverage many approaches that span diverse fields including bacterial genetics, bacterial physiology, protein engineering, biochemistry, and apply a variety of omic approaches (microbiomics, transcriptomics, proteomics, and metabolomics) in vitro and in vivo to define the mechanisms behind how the gut microbiota provides colonization resistance against C. difficile. One of the many essential functions of the indigenous gut microbiota is its ability to maintain colonization resistance and to prevent establishment and growth of pathogens in the gut. There has been a great deal of research in this area trying to define the mechanisms by which the gut microbiota mediates colonization resistance. Potential mechanisms include competition for nutrients, taking up physical space or biomass, production of inhibitory products, and shaping the host immune response. A popular model organism used to interrogate these mechanisms is Clostridioides difficile due to its exquisite sensitivity to changes in the gut microbiota structure and function. C. difficile is an anaerobic, spore-forming, Gram-positive bacterium first isolated in 1935 and the causative agent for C. difficile infection (CDI). Unlocking how C. difficile is able to benefit from the loss of colonization resistance in the gut has major implications for development of therapeutics for prevention and treatment of CDI. My long-term goal is to understand how the gut microbiota mediates colonization resistance against C. difficile. The overall objective of this application is to determine the relationship between nutrient availability (amino acids) and bile acid metabolism in the context of colonization resistance against C. difficile. Based on preliminary data our hypothesis is that amino acid availability influences secondary bile acid production by commensal Clostridia, which will alter colonization resistance against C. difficile. In order to investigate this hypothesis, we plan to alter amino acid abundances in defined and rich media in vitro, and use defined diets in vivo to understand how this impacts secondary bile acid production of commensal Clostridia. Leveraging our robust and reproducible germfree and antibiotic treated mouse models of CDI, we will determine how these metabolic processes affect the establishment and growth of C. difficile, as well as the surrounding gut microbial community. Using novel platforms like LC-IMS-MS and Protein-SIP, we will define the gut metabolome and metaproteome in the context of colonization resistance. The contribution of the proposed research is significant as it seeks to move away from untargeted therapies like FMT and move toward a targeted approach, whereby we can use diet (amino acids) to control secondary bile acid production by commensal Clostridia, restoring colonization resistance against C. difficile. The findings in this proposal will advance understanding of microbe-microbe interactions, host-microbe interactions, and improve microbiome-based therapeutics. Beyond C. difficile it has the potential to allow us to intelligently design customized therapeutic interventions to target human health conditions in the complex ecological environment of the human intestine.

项目总结/摘要 在Theriot实验室，我们应用尖端技术和高通量方法来分析肠道 微生物组和代谢组使用一系列实验技术和动物模型。 我们利用许多 方法跨越不同的领域，包括细菌遗传学，细菌生理学，蛋白质工程， 生物化学，并应用各种组学方法（微生物组学，转录组学，蛋白质组学， 代谢组学），以确定肠道微生物群如何提供 对C.很难 固有肠道微生物群的许多基本功能之一是其维持定植的能力 抵抗力，并防止肠道中病原体的建立和生长。有很多 该领域的研究试图确定肠道微生物群介导定植的机制 阻力潜在的机制包括竞争养分，占用物理空间或生物量， 产生抑制性产物，并形成宿主免疫应答。一种流行的模式生物， 由于其对肠道变化的敏感性， 微生物群的结构和功能。C.艰难梭菌首先是一种厌氧的、形成孢子的革兰氏阳性细菌 1935年分离到的C.艰难梭菌感染（CDI）。解锁如何C。difficile能够 肠道中定植抵抗力丧失的益处对肠道疾病的发展具有重要意义。 用于预防和治疗CDI的治疗剂。 我的长期目标是了解肠道微生物群如何介导对C的定植抗性。很难 本申请的总体目标是确定养分有效性（氨基） 酸）和胆汁酸代谢的背景下，殖民抵抗C。很难基于 初步数据我们的假设是，氨基酸的可用性影响二级胆汁酸的生产， 嗜盐梭菌，这将改变对C。很难为了调查这件事 假设，我们计划在体外改变限定和丰富培养基中的氨基酸丰度，并使用限定的饮食， 体内，以了解这如何影响肠道梭菌的次级胆汁酸产生。利用我们 稳健和可重复的无菌和抗生素治疗的CDI小鼠模型，我们将确定这些 代谢过程影响C.艰难梭菌，以及周围的肠道微生物 社区使用LC-IMS-MS和Protein-SIP等新平台，我们将定义肠道代谢组， 在殖民抵抗的背景下的元蛋白质组。 拟议研究的贡献是重要的，因为它试图摆脱非靶向治疗 喜欢FMT，并朝着有针对性的方法迈进，据此，我们可以使用饮食（氨基酸）来控制继发性 胆汁酸的生产，恢复对C.很难这些发现 在这项提案中，将促进对微生物-微生物相互作用、宿主-微生物相互作用和 改进基于微生物组的疗法。超越C。它有可能让我们聪明地 设计定制的治疗干预措施，以针对复杂生态环境中的人类健康状况， 人体肠道的环境。