RIDGE: Tipping Points in the Evolution of Submarine Hydrothermal Systems: Habitat Generation, Organic Transformation, and Rock Alteration

该奖项是根据2009年《美国复苏和再投资法》(公法111-5)资助的。极端环境中的微生物栖息地和脊峰热液系统的有机变化正受到越来越多的关注，因为生活在这些环境中的微生物的新特性在生物勘探天然产品方面变得越来越重要，可以从这些产品中提取新的药物。这项研究是理论性质的，旨在通过计算“临界点”(即，触发矿物反应和/或流体演化中最戏剧性变化的温度、压力和组成条件)来指导此类微生物的发现。这项工作的重点是来自Ridge 2000综合研究场地的已知热液喷口系统，那里有大量的热液喷口流体成分和矿物数据。该项目的目标是利用热力学约束和计算来预测居住在海底热液喷口的微生物群落的化学能量供应。它还将侧重于将对数百种额外有机化合物的估计添加到热力学数据库中，以便能够对有机转化和有机化合物的非生物合成进行更完整和现实的计算。计算将检查存在于大洋中脊环境中的火成岩基岩和沉积物的全部成分范围。通过专注于定位和理解临界点，拟议的工作不同于大多数以前的理论工作，并提供了一种新的方式来看待热液系统的演变，并确定高温或其他独特微生物生命形式的最佳采样地点。这项工作的更广泛影响包括学生培训、为科学提供亟需的有机化合物热力学数据方面的基础设施建设，以及公众宣传。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Microbial habitats in extreme environments and organic transformations at ridge-crest hydrothermal systems are receiving increased attention as the novel properties of microbes that live in these environments become increasingly important in terms of bioprospecting for natural products from which new drugs can be made. This research is theoretical in nature and designed to guide the discovery of such micro-organisms by calculating "tipping points" (i.e., temperature, pressure, and compositional conditions that trigger the most dramatic changes in mineral reactions and/or fluid evolution). The focus of the work is on known hydrothermal vent systems from the Ridge 2000 Integrated Study Sites where extensive hydrothermal vent fluid compositions and mineral data are present. Goals of the project are to use thermodynamic constraints and calculations to predict the supply of chemical energy to microbial communities that inhabit seafloor hydrothermal vents. It will also focus on adding estimates of hundreds of additional organic compounds to thermodynamic databases to allow more complete and realistic calculations of organic transformations and the abiotic synthesis of organic compounds. Calculations will examine the full compositional ranges of igneous basement rocks and sediments that exist in mid-ocean ridge settings. By focusing on locating and understanding tipping points, the proposed work departs from most previous theoretical work, and provides a new way of looking at the evolution of hydrothermal systems and identifying the best locations to sample for high temperature or other unique microbial life forms. Broader impacts of the work include student training, building infrastructure for science in terms of providing much needed thermodynamic data for organic compounds, and public outreach.