LEXEN: Effects of Microbial Activity on Rates of Basalt Alteration

- 你好微生物活动对玄武岩变化率的影响大约四分之三的海底是玄武岩，提供了适合许多已知微生物物种的化学和物理环境。这种海洋地壳是与海洋进行化学交换的巨大来源和汇，玄武岩/海水化学反应释放的能量是微生物的资源。从全球地球化学的角度来看，微生物在这种化学交换中的作用是一个重要的问题。从天体生物学的角度来看，深海地壳是一个极其稳定的环境，深海玄武岩中的微生物可能是地球上最原始的生物。对微生物沉淀矿物和矿物中微生物标记的研究也与寻找其他由水和岩石组成的行星体上的生命证据有关。该项目探索了培养直接与深海玄武岩相互作用的微生物的新策略。将使用潜水器收集海底裸露的玄武岩，将岩石隔离在密封容器中，并将示踪剂放入容器中以评估污染情况。将利用分子生物学和显微镜技术来鉴定生物并研究它们与玄武岩的相互作用，将利用稀释培养法来寻找纯培养物，将利用微束化学分析来鉴定微生物蚀变玄武岩的矿物学产物。ICP-质谱法将用于监测元素从玄武岩释放到溶液中。该项目与LExEn的目标有关：（1）了解化学通量极小的生命支持环境，（2）促进跨学科研究-在这种情况下，微生物学和地质学学科密切相关，（3）探索地球上可能存在于太阳系行星或卫星上的环境。

LEXEN: Effects of Microbial Activity on Rates of Basalt AlterationAbout three quarters of the ocean floor is basalt, providing chemical and physical environments that are suitable for many known microbial species. This ocean crust is a vast source and sink for chemical exchange with the ocean, and basalt/seawater chemical reactions release energy that is a resource for microorganisms. From a global geochemical perspective, the role of microbes in this chemical exchange is an important issue. From an astrobiological perspective, the deep ocean crust is an extremely stable environment and microbes in deep sea basalts may be some of the most primitive organisms on Earth. Study of microbially precipitated minerals and microbial marks in minerals is also relevant to the search for evidence of life on other planetary bodies composed of water and rock. This project explores a new strategy for culturing microorganisms that directly interact with deep sea basalts. A submersible will be used to collect exposed basalts from the sea floor, and to isolate the rocks in sealed containers and introduce tracers into the containers to evaluate contamination. Molecular biology and microscopy techniques will be used to identify organisms and study their interactions with the basalt, and dilution culture methods will be used to search for pure cultures.Mineralogical products of the microbially alterated basalts will be identified by microbeam chemical analysis. ICP-mass spectroscopy will be used to monitor the release of elements from the basalts into solution. This project is relevant to the LExEn objectives (1) of understanding life supporting environments where chemical fluxes are extremely small, (2) of fostering interdisciplinary research - in this case the disciplines of microbiology and geology are closely linked, and (3) of exploring environments on Earth that are likely to exist on planets or moons in the solar system.