Team Play: Determining Syntrophic Interactions in Hydrocarbon Biodegradation Processes

团队合作：确定碳氢化合物生物降解过程中的互养相互作用

• 批准号: RGPIN-2020-07029
• 负责人: Gieg, Lisa
• 金额: $ 3.06万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=744740
• 关键词: Team; Play; Determining; Syntrophic; Interactions

Microorganisms in the natural world exist as mixed communities whose collective metabolism substantially contributes to biogeochemical and/or nutrient cycling - phenomena that can have profound impacts on global health including our climate, water, and land resources. In anoxic environments, mixed microbial communities comprised of Bacteria and Archaea are able to biotransform organic matter to methane through a metabolic process known as syntrophy. Syntrophy is defined as a thermodynamically interdependent (mutualistic) metabolism wherein different species within mixed anaerobic communities must cooperate to carry out a given metabolic reaction that cannot be catabolized by each organism alone. Such `team play' metabolism operates near the thermodynamic equilibrium, yet contributes substantially to the natural cycling of organic matter to CH4 and CO2 in anoxic ecosystems such as wetlands, animal guts, landfills, rice paddies, and wastewater treatment systems, and is a prevalent process in anoxic hydrocarbon-associated ecosystems such as natural oil and gas seeps, deep subsurface energy reservoirs, and shallow hydrocarbon-contaminated groundwater systems. However, the ecological principles underlying the syntrophic metabolism of most organic compounds, including hydrocarbons, remain to be fully explored. The over-arching, long-term objective of my research program is to determine the interactions that govern syntrophic communities associated with methanogenic hydrocarbon biodegradation processes. The two major short-term objectives for the proposed work that will address gaps in knowledge in this field of study are to (1) identify the interactions and potential roles of poorly understood syntrophic members in mixed consortia, including those of uncultivated taxa (such as `Atribacteria') and other community members that have been identified in our hydrocarbon-metabolizing methanogenic cultures and in other environments, and (2) to experimentally assess mechanisms used by methanogenic hydrocarbon-degrading community members (such as via indirect or direct interspecies electron transfer, mediators, or nutrient interdependencies) to form mutually beneficial partnerships with each other. The proposed research program will offer insights into how microbial community members collectively interact to biotransform organic matter thus contributing to a broader understanding of biogeochemical cycling. The focus on hydrocarbon-degrading systems undergoing such `team play' will help to improve our understanding of how best to apply biological solutions to remediate hydrocarbon-contaminated environments in Canada and elsewhere.

自然界中的微生物以混合群落形式存在，其集体代谢对生物地球化学和/或养分循环做出了重大贡献，这些现象可能对全球健康（包括我们的气候、水和土地资源）产生深远影响。在缺氧环境中，由细菌和古细菌组成的混合微生物群落能够通过称为互养的代谢过程将有机物生物转化为甲烷。协同营养被定义为热力学上相互依赖（互惠）的代谢，其中混合厌氧群落内的不同物种必须合作来进行特定的代谢反应，而该反应不能被每个生物体单独分解代谢。这种“团队合作”代谢在热力学平衡附近运行，但在湿地、动物内脏、垃圾填埋场、稻田和废水处理系统等缺氧生态系统中对有机物自然循环为CH4和CO2有很大贡献，并且是一种普遍存在的代谢机制。缺氧碳氢化合物相关生态系统（例如天然石油和天然气渗漏、深层地下能源库和浅层碳氢化合物污染的地下水系统）中的过程。然而，包括碳氢化合物在内的大多数有机化合物互养代谢的生态原理仍有待充分探索。我的研究计划的总体长期目标是确定与产甲烷碳氢化合物生物降解过程相关的互养群落的相互作用。拟议工作的两个主要短期目标将解决该研究领域的知识差距，即（1）确定混合群落中知之甚少的互养成员的相互作用和潜在作用，包括未开化的分类单元（例如“Atribacteria”）和在我们的碳氢化合物代谢产甲烷培养物和其他环境中已鉴定的其他群落成员，以及（2）通过实验评估产甲烷碳氢化合物降解群落成员使用的机制（例如通过间接或直接的种间电子转移、介体或营养相互依赖性），以形成彼此互惠互利的伙伴关系。拟议的研究计划将深入了解微生物群落成员如何共同相互作用以生物转化有机物，从而有助于更广泛地了解生物地球化学循环。对经历这种“团队合作”的碳氢化合物降解系统的关注将有助于提高我们对如何最好地应用生物解决方案来修复加拿大和其他地方碳氢化合物污染环境的理解。