Understanding syntrophic hydrocarbon metabolism under methanogenic conditions

了解产甲烷条件下的互养碳氢化合物代谢

• 批准号: RGPIN-2015-05214
• 负责人: Gieg, Lisa
• 金额: $ 2.77万
• 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: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=651846
• 关键词: Understanding; syntrophic; hydrocarbon; metabolism; under

Hydrocarbon spills into subsurface environments such as groundwater aquifers frequently lead to the development of methanogenic conditions. Many studies have shown that hydrocarbons can be biodegraded to methane by microbes, suggesting that we may be able to rely on such microbial activity for contaminated site clean up. To do so, we must have a better understanding of how this metabolism operates in order to determine the advantages and limitations of relying on methanogenic consortia for remediation. Syntrophy, meaning `feeding together', is a mode of microbial metabolism wherein different species must cooperate (for thermodynamic reasons) to carry out metabolic processes. Syntrophic microbial processes play key roles in large-scale beneficial industrial processes such as waste water treatment and make significant contributions to carbon cycling in anaerobic ecosystems. As such, syntrophy has mainly been studied using microbes that metabolize relatively simple carbon sources (such as fatty acids). As with fatty acids, methanogenic hydrocarbon metabolism must occur via syntrophic processes wherein cooperation among microbial species is needed to break down a given hydrocarbon to carbon dioxide and methane. However, little is known about the ecological principles of syntrophy in hydrocarbon-containing methanogenic ecosystems. Thus, the long-term objective of this research program is to elucidate the fundamental scientific principles underlying syntrophic hydrocarbon metabolism under methanogenic conditions that will be accomplished via two major short-term objectives. Objective 1 will be to improve upon and/or develop new strategies for cultivating syntrophic hydrocarbon-degrading methanogenic consortia in order to decrease lag times and improve rates of metabolism to enable more efficient study of syntrophic hydrocarbon metabolism. This objective will use a cultivation approach to test the use of various medium additives, solid supports, and growth conditions to improve rates of metabolism. Objective 2 will be to identify and quantify the key syntrophy genes and hydrocarbon-degrading genes that are expressed during methanogenic hydrocarbon metabolism using molecular biology approaches. This information is currently unknown. The proposed research will address major gaps in the fields of syntrophy and methanogenic hydrocarbon metabolism, leading to fundamental scientific discoveries and potential applications for contaminated site remediation.  The outcome of the research will be of great benefit to Canada by helping to ensure clean environments (such as groundwater resources). Through the proposed program, many highly qualified personnel will be trained in diverse technical skills (ranging from analytical chemistry to genomics) and soft skills (leadership, communication) that will position them well for jobs in academia, industry, or government.

碳氢化合物泄漏到地下环境，如地下水含水层，往往导致产生甲烷的条件的发展。许多研究表明，碳氢化合物可以被微生物生物降解为甲烷，这表明我们可以依靠这种微生物的活动来清理受污染的场地。要做到这一点，我们必须更好地了解这种新陈代谢是如何运作的，以便确定依赖产甲烷联合体进行补救的优势和局限性。合并体，意思是“一起进食”，是一种微生物代谢模式，不同物种必须合作(出于热力学原因)才能进行代谢过程。合养微生物过程在废水处理等大规模有益的工业过程中发挥着关键作用，并对厌氧生态系统中的碳循环做出了重要贡献。因此，主要使用代谢相对简单的碳源(如脂肪酸)的微生物来研究联会。与脂肪酸一样，产甲烷碳氢化合物的代谢必须通过同步营养过程进行，在这种过程中，需要微生物物种之间的合作才能将给定的碳氢化合物分解为二氧化碳和甲烷。然而，对含烃产甲烷生态系统中的合成营养的生态学原理知之甚少。因此，这项研究计划的长期目标是阐明在产甲烷条件下的合养碳氢化合物代谢的基本科学原理，这将通过两个主要的短期目标来实现。目标1将改进和/或开发培养合养碳氢化合物降解产甲烷联合体的新策略，以减少滞后时间和提高代谢率，从而能够更有效地研究合养碳氢化合物代谢。这个目标将使用培养方法来测试使用各种介质添加剂、固体载体和生长条件来提高新陈代谢速度。目标2将利用分子生物学方法鉴定和量化在产甲烷烃代谢过程中表达的关键合成基因和烃降解基因。这一信息目前尚不清楚。拟议的研究将解决合成和产甲烷烃代谢领域的重大空白，导致基础科学发现和污染场地修复的潜在应用。研究结果将有助于确保清洁的环境(如地下水资源)，从而对加拿大大有裨益。通过拟议的计划，许多高素质的人员将接受各种技术技能(从分析化学到基因组学)和软技能(领导力、沟通)的培训，这将使他们能够很好地胜任学术界、工业界或政府的工作。