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

智力价值：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。理解生命如何在深海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，这些化合物来自于沉积物被埋藏并暴露在高温和压力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和实验上检验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。这些高温高压反应产生的有机溶质向上输送到地下有人居住的区域。这项研究的主要重点是确定热水和有机物之间的反应是如何产生最终供应深层生物圈的小型有机化合物的。第一阶段侧重于众所周知的水热实验，这些反应在高温和高压下将简单的碳氢化合物转化为醇、酮和羧酸。第二阶段探索了同样的反应，但在一个更现实的、因此是复杂的地质系统的背景下，该地质系统包括在所有有机丰富的沉积物和沉积岩中发现的粘土矿物。这些反应中的大多数还没有在地质现实条件下进行系统的研究。因此，我们目前对这些转化机制的本质理解是推测性的。这项工作产生了严格的结果，可以根据这些结果计算出地球深处的微生物代谢潜力？？S地壳。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有机质转化的新的预测性、机械性模型。新的模型将为那些为未来探索深层生物圈的海洋和大陆钻探工作进行选址的人提供信息，并将使我们能够更好地了解石油的生成。该项目还提供了一种方法，可以预测在哪里可以发现具有特殊性质的新微生物物种的勘探。水热反应堆办法还可提供焚烧或掩埋有机废物的绿色替代办法。在教育和培训方面，这项工作支持博士后、研究生和本科生，并支持在科学界性别代表性不足的个人投资机构。公众宣传将包括为？I？M学院方向？开发新的材料？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球/地球科学演示，并协调学生志愿者。演示、作业和教案将在“我要上大学”的网站上发布和传播。

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.