LEXEN: Pyrite, a Crucial Mineral and Surface for Microbial Life in Extreme Hydrothermal Environments (Collaborative Research)

LEXEN：黄铁矿，极端热液环境中微生物生命的重要矿物和表面（合作研究）

• 批准号: 9714302
• 负责人: George Luther
• 金额: $ 46.13万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-01-01 至 2001-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9714302&HistoricalAwards=false
• 关键词: LEXEN; Pyrite; Crucial; Mineral; Surface

9714302 Luther PROJECT SUMMARY Organisms that thrive in high temperature (hyperthermophiles) ecosystems such as at terrestrial and deep-sea hydrothermal vents, have challenged our understanding of the physical and biochemical constraints on the upper temperature limits for life and stimulated new theories on how life originated (e.g. Baross and Hoffman, 1985; Pace, 1991). These hyperthermophiles are the most closely related to the universal ancestor for all life (from small subunit rRNA and gene duplication data) which supports the theory that life arose in highly reduced, high temperature environments such as those encountered at hydrothermal vent systems. Recently scientists proposed a mechanism for the synthesis of the first molecules for life in which pyrite can be synthesized abiotically with hydrogen as a product, laying the framework for the evolution of the first metabolic cycles. The central hypothesis of this study maintains that the abiotic synthesis of pyrite provides the essential properties for sequestering the energy sources for chemoautotrophic metabolism of the deepest lineages of life. Drs. Luther and Reysenbach believe that under an extreme chemical and physical environment microorganisms can utilize the resources provided on the pyrite surfaces for sustained metabolism. They also believe that these organisms will closely represent early life forms that may have occupied similar extreme habitats. Furthermore, since molecular phylogenetic evidence exists that the deepest of these thermophilic lineages inhabit iron and sulfidic-rich environments at deep-sea hydrothermal vents, they are well-positioned to test these assertions. The objective of this research are: 1. To establish whether pyrite and the associated adsorbed trace metals and simple inorganic molecules will mediate the microbial community structure in high temperature aquatic environments. 2. To determine whether pyrite synthesi s can be predicted, through the simultaneous measurement of FeS and hydrogen sulfide. This project clearly addresses most of the primary mandates of the LExEn research program. In this interdisciplinary study these collaborators will integrate molecular genetic approaches with in situ geochemistry to study the diversity, ecology, and evolutionary history of the microorganisms thriving in extreme habitats where intense redox and temperature gradients exist. This project is cooperatively supported by the Divisions of Ocean Science and Chemistry, and the Office of Multidisciplinary Activities of the Mathematical and Physical Sciences Directorate

小行星9714302 项目摘要 在陆地和深海热液喷口等高温（超嗜热生物）生态系统中茁壮成长的生物挑战了我们对生命温度上限的物理和生物化学限制的理解，并激发了关于生命如何起源的新理论（例如Baross和霍夫曼，1985年; Pace，1991年）。这些超嗜热菌与所有生命的普遍祖先关系最密切（从小亚基rRNA和基因复制数据来看），这支持了生命出现在高度还原的高温环境中的理论，例如在热液喷口系统遇到的环境。 最近，科学家提出了一种合成第一个生命分子的机制，其中黄铁矿可以以氢为产物非生物合成，为第一个代谢周期的进化奠定了框架。本研究的中心假设认为，黄铁矿的非生物合成提供了必要的性能，为封存能源的最深的生命谱系的化能自养代谢。Luther和Reysenbach博士认为，在极端的化学和物理环境下，微生物可以利用黄铁矿表面提供的资源进行持续的新陈代谢。他们还认为，这些生物将密切代表可能占据类似极端栖息地的早期生命形式。 此外，由于存在分子系统发育证据表明，这些嗜热谱系中最深的存在于深海热液喷口富含铁和硫化物的环境中，因此它们完全有能力检验这些断言。 本研究的目的是：1.确定高温水环境中黄铁矿及其吸附的微量金属和简单无机分子是否会调节微生物群落结构。2.通过同时测定硫化亚铁和硫化氢的含量，确定能否预测黄铁矿的合成。该项目明确解决了LExEn研究计划的大部分主要任务。在这项跨学科研究中，这些合作者将分子遗传学方法与原位地球化学相结合，研究在极端栖息地中蓬勃发展的微生物的多样性，生态学和进化历史，其中存在强烈的氧化还原和温度梯度。 该项目得到了海洋科学和化学司以及数学和物理科学局多学科活动办公室的合作支持