EAGER: Developing functional gene based biomarker for DAMO and exploring the potential application of DAMO in wastewater treatment

1657725 goel厌氧过程是有用的，使污水处理厂成为能源中性，甚至可能是积极的能源。厌氧过程的有用副产品之一是甲烷气体，它可以用作燃料。这项研究结合了地表水中两种重要的生物地球化学循环——氮和碳循环——以及两种重要的污染物——甲烷和氮。这个项目将有助于解决21世纪国家工程院面临的重大挑战之一，即管理氮循环。最近的研究表明，在无氧条件下，以亚硝酸盐和硝酸盐为电子受体的甲烷氧化是可能的，称为反硝化缺氧甲烷氧化。反硝化缺氧甲烷氧化具有重要的生态意义，因为它连接了两个重要的生态系统循环-氮循环和碳循环。反硝化缺氧甲烷氧化生物的作用不容忽视；这些生物对生态系统中的甲烷汇和氮污染生态系统中的氮动态都有贡献。最近与反硝化缺氧甲烷氧化有关的发现涉及对原核生物介导的甲烷氧化的生物化学的补充，并产生了进一步的研究可能性，例如评估它们在全球范围内的作用、它们的生态多样性以及它们在甲烷汇中的实际作用。一氧化氮歧化酶参与一氧化氮（2NO=N2+O2）的分裂，生成氧气供颗粒甲烷单加氧酶氧化甲烷气体。基于M. oxyfera的宏基因组构建和初步的稳定同位素标记实验，我们假设M. oxyfera具有将NO分解为N2和O2的能力。绝对没有关于一氧化氮歧化酶的信息。在更广泛的范围内，反硝化缺氧甲烷氧化生物的生态意义、反硝化缺氧甲烷氧化引起的甲烷汇的实际规模以及影响反硝化缺氧甲烷氧化的原位因素尚不完全清楚。利用反硝化缺氧甲烷氧化生物在污水处理厂进行氮管理的潜力已经通过精心规划的操作策略得到了充分的探索。在这个EAGER奖项中，PI将研究一氧化氮歧化酶基因的作用，并确定该基因的研究是否可以为理解反硝化缺氧甲烷氧化生物的生态学提供突破。该项目将研究反硝化缺氧甲烷氧化生物的脱氮潜力，同时在废水处理中与其他n循环细菌协同工作。本研究的智力价值包括：(1)阐明反硝化耦合缺氧甲烷氧化（反硝化甲烷氧化）是否是氮污染生态系统中甲烷的关键汇；(2)利用元基因组学和元转录组学揭示反硝化缺氧甲烷氧化生物的身份；(3)开发了一种新的工具来研究反硝化缺氧甲烷氧化生物的存在和多样性。该项目将为进一步研究和将反硝化缺氧甲烷氧化纳入旨在估算甲烷排放的生态模型奠定基础。在本研究中获得的基本知识将适用于其他自然（污染的地下和河流沉积物）和工程（工程生物反应器）系统。该项目将直接促进研究生和本科教育。PI已经开发了计算机动画来演示病毒是如何感染细菌的。在这个项目中，PI将进一步扩大这一范围，包括制作配有精美插图的短片，以展示实验室规程、氮循环的重要性和温室气体排放。研究结果将通过同行评审的出版物和为当地湿地管理者举办的社区讲习班传播。

1657725GoelAnaerobic processes are useful and enable wastewater treatment plants to become energy neutral or, possibly, energy positive. One of the useful byproducts of anaerobic processes is methane gas, which can be utilized as a fuel. This research combines two important biogeochemical cycles - the nitrogen and carbon cycles - and two important contaminants - methane and nitrogen - in surface waters. This project will contribute to solving one of the National Academy of Engineering Grand Challenges of the 21st century, managing the nitrogen cycle.Recent findings suggest that methane oxidation is possible in oxygen-free conditions with nitrite and nitrate as the electron acceptors, referred to as denitrifying anoxic methane oxidation. Denitrifying anoxic methane oxidation is ecologically significant because it connects two important ecosystem cycles - the nitrogen and carbon cycles. The role of denitrifying anoxic methane oxidation organisms cannot be ignored; these organisms contribute to the sink of methane in ecosystems as well as to the nitrogen dynamics in nitrogen-contaminated ecosystems. Recent findings related to denitrifying anoxic methane oxidation involve an addition to the biochemistry of prokaryotes-mediated methane oxidation and have generated further possibilities for research, such as an evaluation of their role on a global scale, their ecological diversity, and their actual role in methane sinks. The enzyme nitric oxide dismutase is involved in the splitting of nitric oxide (2NO=N2+O2) to generate oxygen for the particulate methane monooxygenase to oxidize methane gas. Based on the metagenome construction of M. oxyfera and preliminary stable isotope labeled experiments, it was hypothesized that M. oxyfera is capable of dismutating NO to N2 and O2. Absolutely no information is available on nitric oxide dismutase. On a broader scale, the ecological significance of denitrifying anoxic methane oxidation organisms, the actual scale of methane sinks due to denitrifying anoxic methane oxidation, and the in-situ factors affecting denitrifying anoxic methane oxidation are not fully understood. The potential of using denitrifying anoxic methane oxidation organisms for nitrogen management in wastewater treatment plants has been explored fully with well-planned operational strategies. In this EAGER award, the PI will study the role of the nitric oxide dismutase gene and determine whether studies of this gene could provide a breakthrough in understanding the ecology of denitrifying anoxic methane oxidation organisms. The PI will study the nitrogen removal potential of denitrifying anoxic methane oxidation organisms while working synergistically with other N-cycling bacteria in wastewater treatment. The intellectual merit of this research includes: (1) elucidating whether denitrification-coupled anoxic methane oxidation (denitrifying anoxic methane oxidation) is a key sink of methane in nitrogen-contaminated ecosystems, (2) revealing the identity of denitrifying anoxic methane oxidation organisms using metagenomics and metatranscriptomics, and, (3) developing a new tool to study the presence and diversity of denitrifying anoxic methane oxidation organisms. This project will lay the foundation for further investigation and incorporation of denitrifying anoxic methane oxidation in ecological models aimed at estimating methane emissions. The fundamental knowledge gained in this research will be applicable in other natural (contaminated subsurface and river sediments) and engineered (engineered bioreactors) systems. The project will directly contribute to graduate and undergraduate education. The PI has developed computer animations to demonstrate, for example, how viruses infect bacteria. In this project, the PI will further expand this outreach to include well-illustrated short films to demonstrate laboratory protocols, the significance of the nitrogen cycle, and greenhouse gas emissions. Results will be disseminated through peer-reviewed publications and community workshops for local wetland managers.