Defining the molecular basis of microbial syntrophy using synthetic communities

这项研究项目涉及对一组被称为合养细菌的鲜为人知的微生物及其产甲烷古菌伙伴的研究，这些微生物在所有自然产生的生物质的厌氧循环中发挥着关键作用。它们的功能是微生物群落的成员，微生物群落消耗腐烂的动植物物质，并将其转化为植物和藻类光合作用所需的起始物质。合养细菌首先分解和回收小有机分子，如脂肪、氨基酸和小芳香化合物。由此产生的废物(醋、水和氢气)然后被第二类称为产甲烷菌的微生物利用，以产生更多的水以及二氧化碳和甲烷。甲烷可以被收获并用作可再生能源供应。通过这种合作，这两种微生物都获得了在两种微生物都无法单独生存和生长的环境中生存和生长的能量。使用分子和生化工具的组合来研究每个微生物中以前未描述的新陈代谢，并了解它们如何相互合作，以最佳地回收自然界中的废物。将对底物转化中使用的酶进行鉴定和表征，并研究细胞如何完成代谢物的交换。这一新知识将有助于建模和预测碳在不同环境中如何循环，以及这些过程如何影响地球生物圈的正常维护。此外，它还将提高我们将不需要的废物回收为可再生能源供应的能力。在外展活动中，将编写网上学习材料，并用于加强两所院校的本科微生物学教学。此外，PIs将在几个欠发达国家开展外联活动，以促进当地可持续应用于废物处理和能源生产。同步代谢在几乎所有厌氧生态系统中都是必不可少的，但对驱动相关生态转变的分子、生化或生理事件知之甚少。在这里，由不同种类的细菌和古菌组成的微生物群落在代谢平衡中运行，以推动全球碳循环和生态系统功能。PI假设，共同营养的伙伴使用专门的生化和适应系统来完成社区驱动的新陈代谢。为了检验这一点，我们将使用沃尔菲合胞单胞菌/亨加特甲烷杆菌共培养模型系统来阐明合养伙伴关系的形成和维持的基本原理。高通量技术的组合，包括全基因组蛋白质组图谱和基因双杂交筛选，将被用于识别参与脂肪酸分解代谢的代谢和调节网络。随后将对碳氧化和电子流动所需的关键蛋白质进行生化表征，直至氢气和二氧化碳的形成，这是一个热力学上困难的过程。还将研究建立和维持相关但不同的共培养伙伴关系所需的分子事件，即沃尔菲杆菌和反胃甲烷杆菌之间的伙伴关系。所获得的信息将为模拟和预测其他多物种微生物群落的相关过程提供基础。新知识将用于开发废物处理和能源生产的创新解决方案，并设计生物甲烷化和微生物燃料系统，为废水处理提供当地可持续的应用。该奖项由分子和细胞生物科学部的细胞动力学和功能以及系统和合成生物学项目共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This research project addresses the study of a group of poorly understood microorganisms called syntrophic bacteria and their methanogenic archaea partners that play essential roles in the anaerobic recycling of all naturally occurring biomass. They function as members of microbial communities that consume decaying plant and animal material and convert it back into the starting materials needed for photosynthesis by plants and algae. The syntrophic bacteria first break down and recycle small organic molecules such as fats, amino acids and small aromatic compounds. The resulting waste products (vinegar, water and hydrogen gas) are then used by a second group of microbes called methanogens to generate more water plus carbon dioxide and methane. Methane can be harvested and used as a renewable energy supply. Through this cooperation, both microbes obtain energy to survive and grow in environments where neither could alone. A combination of molecular and biochemical tools is used to study the previously undescribed metabolism in each microbe and to understand how they cooperate with one another to optimally recycle waste materials in nature. The enzymes used in substrate conversion will be identified and characterized; and how cells accomplish the exchange of metabolites will be examined. The new knowledge will assist in modeling and predicting how carbon is recycled in different environments, as well as how these processes affect the normal maintenance of the earth's biosphere. Furthermore, it will improve our ability to recycle unwanted waste materials into renewable energy supplies. In outreach activities, web-based learning materials will be generated and used to enhance undergraduate microbiology instruction at both institutions. In addition, the PIs will perform outreach activities in several under-developed countries to facilitate the development of locally sustainable applications for waste treatment and energy production.Syntrophic metabolism is essential in nearly all anaerobic ecosystems, yet very little is understood about the molecular, biochemical, or physiological events that drive the associated ecological transformations. Here, microbial communities composed of distinct species of bacteria and archaea operate in metabolic balance to drive global carbon cycling and ecosystem functioning. The PIs hypothesize that specialized biochemical and adaptive systems are used by the syntrophic partners to accomplish their community-driven metabolism. To examine this, the model Syntrophomonas wolfei/Methanosprillum hungatei co-culture system will be employed to elucidate basic principles governing formation and maintenance of the syntrophic partnership. A combination of high-throughput technologies, including genome-wide proteomic profiling and genetic two hybrid screens, will be employed to identify the metabolic and regulatory networks involved in fatty acid catabolism. This will be followed by the biochemical characterization of key proteins needed for carbon oxidation and electron flow down to the formation of H2 and CO2 which is a thermodynamically difficult process. The molecular events required to establish and maintain a related but distinct co-culture partnership, that between S. wolfei and Methanobrevibacter ruminantium will also be examined. The resulting information will provide a foundation to model and predict related processes by other multispecies microbial communities. The new knowledge will be used to develop innovative solutions for waste treatment and energy production and to engineer bio-methanation and microbial fuel systems to provide locally sustainable applications for wastewater treatment. This award is jointly funded by the Cellular Dynamics and Function and the Systems and Synthetic Biology Programs in the Division of Molecular and Cellular Biosciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.