The Nature of Bacterial Uncultivability

细菌不可培养的本质

• 批准号: 7259543
• 负责人: Kim Lewis
• 金额: $ 23.55万
• 依托单位: NORTHEASTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-17 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7259543
• 关键词: Adenosylhomocysteine nucleosidase; Area; Bacteria; Cells; Coculture Techniques; Code; Diffusion; Discipline; Disruption; Drug Metabolic Detoxication; Drug resistance; Elements; Environment; Escherichia coli; Genes; Genetic; Goals; Growth; Growth Factor; Health; High Pressure Liquid Chromatography; Homologous Gene; Housekeeping; Human; In Vitro; Intestines; Isopropyl Thiogalactoside; Knock-out; Lead; Libraries; Metabolic; Methods; Microbiology; Modeling; Molecular; Nature; Numbers; Nutrient; Open Reading Frames; Oral; Organism; Parents; Pharmacologic Substance; Plasmids; Polymerase Chain Reaction; Production; Psychrobacter; Research; Science; Screening procedure; Shuttle Vectors; Signal Transduction; Signal Transduction Pathway; Simulate; Source; Testing; Variant; Work; base; expression cloning; expression vector; gallium alloy GF; gene cloning; microorganism; pathogen; prevent; promoter; receptor; response; tool; vector

DESCRIPTION (provided by applicant): The long-term goal of this project is to understand the molecular basis of bacterial unculturability. ~99% of all bacteria do not grow on synthetic media in vitro, which seriously undermines progress in microbiology, including critical areas related to human health. The established paradigm holds that unculturable organisms are either extremely slow growers, or require some unknown nutrients. In this proposal, we will test an alternative signaling hypothesis of unculturability - most microorganisms evolved to grow in a familiar environment, and will only propagate in response to signals from their surroundings. We have previously developed a method to grow unculturable bacteria by culturing them in a diffusion chamber placed in their natural environment (Kaeberlein, T., Lewis, K., and Epstein, S.S. 2002. Isolating "uncultivable" microorganisms in pure culture using a simulated natural environment. Science 296:1127-1129). Our preliminary findings indicate that growth on synthetic media of isolates from the chamber can be achieved by selection for domesticated variants; or in co-culture with "helper" species. These preliminary observations are consistent with the signaling hypothesis and form the basis of the present proposal. The goal of this project is to discover the genes controlling culturability of a model microorganism MSC33 related to culturable Psychrobacter. We were able to isolate a "domesticated" variant of MSC33 that grows well on a variety of synthetic media. This model will enable us to identify the genetic differences between the parent unculturable and the culturable derivative organisms. This work will be facilitated by a shuttle vector we developed based on an endogenous plasmid from MSC33. Finding the first culturability genes is the essential step toward elucidating the signal transduction pathway controlling growth which we will undertake in a subsequent RO1 project. The reasons preventing the majority of microorganisms from growing in the lab are unknown, and microbiology as a discipline has been restricted to the study of 1% of bacterial species. This project will advance our understanding of uncultivable bacteria, and will help develop tools to grow them. Unculturable bacteria are an enormous untapped source of potentially useful pharmaceutical compounds. Unculturable bacteria also make up most of the human oral and intestinal microflora. This project will advance our understanding of uncultivable bacteria, and will help develop tools to grow them. Unculturable bacteria are an enormous untapped source of potentially useful pharmaceutical compounds. Unculturable bacteria also make up most of the human oral and intestinal microflora.

描述（由申请人提供）：该项目的长期目标是了解细菌不种样的分子基础。在所有细菌中，〜99％的细菌在体外没有生长，这严重破坏了微生物学的进展，包括与人类健康有关的关键领域。既定的范式认为，不可养殖的生物要么是生长速度极慢，要么需要一些未知的营养素。在此提案中，我们将测试一种替代性信号假设的种值信号假设 - 大多数微生物都会在熟悉的环境中生长，并且只会响应周围环境的信号而传播。我们以前已经开发了一种方法来通过在其自然环境中放置的扩散室中培养不可培养的细菌（Kaeberlein，T。，Lewis，K。和Epstein，S.S。2002。使用模拟自然环境分离纯培养中的“不可耕种”的微生物。科学296：1127-1129）。我们的初步发现表明，可以通过选择驯化变体来实现从腔室的分离株的合成介质的增长。或与“助手”物种共同培养。这些初步观察结果与信号假设一致，并构成了本提议的基础。该项目的目的是发现控制模型微生物MSC33的培养基的基因，与可培养的精神杆菌有关。我们能够隔离MSC33的“驯化”变体，该变体在各种合成介质上都可以很好地生长。该模型将使我们能够确定父母无法培养和可培养的衍生物生物之间的遗传差异。我们基于MSC33的内源性质粒开发的班车向量将促进这项工作。找到第一个可培养基的基因是阐明信号转导途径控制生长的重要步骤，我们将在随后的RO1项目中进行。防止大多数微生物在实验室中生长的原因尚不清楚，而微生物学作为学科的原因仅限于对1％的细菌物种的研究。该项目将促进我们对不可养殖细菌的理解，并将帮助开发生长它们的工具。不可培养的细菌是潜在有用的药物化合物的巨大未开发的来源。不可培养的细菌还构成了大部分人类口腔和肠道菌群。该项目将促进我们对不可养殖细菌的理解，并将帮助开发生长它们的工具。不可培养的细菌是潜在有用的药物化合物的巨大未开发的来源。不可培养的细菌还构成了大部分人类口腔和肠道菌群。