Minerals as Energy Sources for Microorganisms
Minerals as Energy Sources for Microorganisms
复制标题
DOI：
10.2113/gsecongeo.104.8.1235
复制
发表时间：
2009-12
期刊：
影响因子：
5.8
通讯作者：
E. Shock
中科院分区：
文献类型：
--
作者：
E. Shock
微生物改变矿物质的原因有很多，包括创造更适宜生存的环境、提取营养物质和封存有毒物质。矿物质也可能被微生物代谢的产物被动地改变，例如酸的产生。微生物利用矿物质作为耦合氧化还原反应的电子源和汇，许多这些反应能够从不稳定或亚稳定的矿物质中释放和捕获能量。这些过程可能会产生戏剧性的结果，例如在硫化物矿物氧化过程中产生强酸性溶液，或者在地质时期的风化和成岩作用过程中缓慢而离散地转化矿物。在任何一种情况下，矿物能源都是通过微生物代谢不可逆转地转化的。本文的目的是探讨微生物-矿物质相互作用的几个核心问题，包括：在什么条件下矿物质代表微生物代谢的能量来源？我们如何评估可用能源的数量，以及能源供应最依赖于哪些因素？我们如何从现场和分析数据得到自然系统的能量分析？这个框架用已知的和假定的微生物介导的涉及矿物质的能量生成反应的例子来说明。
Microorganisms alter minerals for a variety of reasons, including generation of more hospitable surroundings, extraction of nutrients, and sequestration of toxic substances. Minerals also may be altered passively by the products of microbial metabolism, such as production of acid. Microbes use minerals as sources and sinks of electrons for coupled oxidation-reduction reactions, and many of these reactions enable the release and capture of energy from unstable or metastable minerals. These processes can have dramatic results, such as the production of intensely acidic solutions during oxidation of sulfide minerals, or they can slowly and discretely transform minerals during weathering and diagenesis over geologic time. In either case, mineral sources of energy are transformed irreversibly by microbial metabolism. The purpose of this paper is to explore several central questions about microbial-mineral interactions, including the following: Under what conditions does a mineral represent an energy source for microbial metabolism? How can we evaluate the amount of energy available, and upon which factors does that energy supply depend most critically? How do we get from field and analytical data to an energy analysis for a natural system? This framework is illustrated with examples of known and postulated microbially mediated energy-yielding reactions involving minerals.