ETBC: Organic Geochemical Transformations and the Deep Biosphere -- Identifying the Food Sources for Microbes in Sedimentary Systems

ETBC：有机地球化学转化和深层生物圈——识别沉积系统中微生物的食物来源

• 批准号: 0826588
• 负责人: Everett Shock
• 金额: $ 147.86万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2014-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0826588&HistoricalAwards=false
• 关键词: ETBC; Organic; Geochemical; Transformations; Deep

Intellectual Merit: This research explores how geochemical processes support microbes living deep in the Earth. A major challenge in understanding how life can survive at depth is the identity and source of organic compounds that are consumed by microbes. While some of these compounds are likely to be produced by other subsurface microbes, this works focuses on the large inventory of consumable organic compounds that comes from geochemical transformations of organic matter that take place as sediments are buried and exposed to elevated temperatures and pressures. Goals of the work are to examine, both theoretically and experimentally, chemical reactions that occur at temperatures and pressures greater than microbial life can withstand. These high temperature and pressure reactions produce organic solutes that are transported upward into the inhabited zones of the subsurface. The primary focus of the research is to determine how reactions between hot water and organic matter generate small organic compounds that ultimately feed the deep biosphere. Phase I focuses on hydrothermal experiments of well-known reactions that transform simple hydrocarbons into alcohols, ketones, and carboxylic acids at elevated temperatures and pressures. Phase II explores these same reactions, but in the context of a more realistic and thus complex geologic system that includes the clay minerals found in all organic rich sediments and sedimentary rocks. Most of these reactions have not been systematically studied under geologically realistic conditions. As a result, our present understanding of these transformation mechanisms in nature are speculative. This work produces rigorous results from which calculations can be made to predict the microbial metabolic potential of areas deep within the Earth?s crust. Broader Impacts: This work provides organic chemists with new methods to control reactions and provides geochemists with new predictive, mechanistic models of organic matter transformations. New models will inform those making site selections for future ocean and continental drilling efforts that explore the deep biosphere and will allow us to better understand the generation of petroleum. This project also provides a means to predict where prospecting of new microbial species with unusual properties can be found. The hydrothermal reactor approach may also provide green alternatives to incineration or burial of organic waste. In terms of education and training, the work supports post-docs, graduate students, and undergraduates, and supports PIs whose gender is under-represented in the sciences. Public outreach will include development new materials for the ?I?m College Bound? program. Graduate and undergraduate researchers associated with this project will help develop new geo/earth science demonstrations and coordinate student volunteers. The demonstrations, assignments and lesson plans will be disseminated and published on the "I'm College Bound" web site.

智力优势：这项研究探索了地球化学过程如何支持生活在地球深处的微生物。了解生命如何在深度生存的一个主要挑战是微生物消耗的有机化合物的身份和来源。虽然其中一些化合物可能是由其他地下微生物产生的，但这项工作的重点是大量可消耗的有机化合物，这些化合物来自沉积物被掩埋并暴露在高温和高压下时发生的有机物的地球化学转化。 这项工作的目标是从理论上和实验上研究在高于微生物生命所能承受的温度和压力下发生的化学反应。 这些高温和高压反应产生有机溶质，这些有机溶质被向上输送到地下的居住区。研究的主要重点是确定热水和有机物之间的反应如何产生最终为深层生物圈提供食物的小有机化合物。第一阶段的重点是众所周知的反应，将简单的碳氢化合物转化为醇，酮和羧酸在高温高压下的水热实验。第二阶段探索这些相同的反应，但在一个更现实，因此复杂的地质系统，包括粘土矿物中发现的所有有机丰富的沉积物和沉积岩的背景下。 这些反应中的大多数尚未在地质现实条件下进行系统研究。 因此，我们目前对自然界中这些转化机制的理解是推测性的。 这项工作产生了严格的结果，从中可以进行计算，以预测地球深处地区的微生物代谢潜力？的外壳。更广泛的影响：这项工作为有机化学家提供了控制反应的新方法，并为地球化学家提供了新的有机物质转化的预测机制模型。新模型将为未来探索深层生物圈的海洋和大陆钻探工作的选址提供信息，并使我们能够更好地了解石油的生成。该项目还提供了一种手段，以预测在何处可以发现具有不寻常特性的新微生物物种，热液反应器方法还可以提供焚化或掩埋有机废物的绿色替代方法。 在教育和培训方面，这项工作支持博士后、研究生和本科生，并支持在科学领域性别代表性不足的专业人员。 公共宣传将包括为《公约》编写新材料。我呢？我上大学了？程序.与该项目相关的研究生和本科生研究人员将帮助开发新的地质/地球科学演示和协调学生志愿者。演示、作业和教案将在“我即将上大学”网站上传播和公布。