Colonization of subsurface microbial observatories deployed in young ocean crust
Colonization of subsurface microbial observatories deployed in young ocean crust
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DOI：
10.1038/ismej.2010.157
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发表时间：
2011-04-01
期刊：
影响因子：
11
通讯作者：
Edwards, Katrina J.
中科院分区：
文献类型：
--
作者：
Orcutt, Beth N.;Bach, Wolfgang;Edwards, Katrina J.
洋壳是地球上最大的水文地质水库，含有与玄武岩壳处于热力学不平衡状态的流体。人们对栖息在这一广阔领域并利用化学有利条件进行代谢活动的微生物生态系统知之甚少。从海洋钻探作业中回收的地壳样本往往无法进行微生物分析，妨碍了确定地下生物圈的范围和功能的努力。我们报告的结果，从第一次在原位实验观测系统已被用来研究海底下的生活。在胡安·德富卡海脊东侧年轻（3.5 Ma）玄武岩地壳中进行了4年的实验，记录了地壳微生物生态系统对不断变化的物理和化学条件的动态钻后反应。扭曲的秸秆表现出生物成因的铁羟基氧化物签名涂层的矿物基板的表面在天文台，这些生物签名表明殖民化的铁氧化细菌在初始阶段的冷却，好氧，富铁的条件下天文台安装。在热和化学恢复到更温暖的还原条件后，观测站的原位微生物结构发生了变化，成为区域地壳流体自然条件的代表。厚壁菌门，代谢潜力是未知的，但可能涉及N或S循环，占主导地位的反弹后的细菌群落。古细菌群落的多样性极低。我们的实验记录了自然水文系统中的原位条件，该系统可以渗透数千年，这体现了观测实验在探索地下玄武岩生物圈方面的力量，玄武岩生物圈是地球上最大但最不了解的生物群落。The ISME Journal（2011）5，692-703; doi：10.1038/ismej.2010.157; 2010年11月25日在线发表
Oceanic crust comprises the largest hydrogeologic reservoir on Earth, containing fluids in thermodynamic disequilibrium with the basaltic crust. Little is known about microbial ecosystems that inhabit this vast realm and exploit chemically favorable conditions for metabolic activities. Crustal samples recovered from ocean drilling operations are often compromised for microbiological assays, hampering efforts to resolve the extent and functioning of a subsurface biosphere. We report results from the first in situ experimental observatory systems that have been used to study subseafloor life. Experiments deployed for 4 years in young (3.5 Ma) basaltic crust on the eastern flank of the Juan de Fuca Ridge record a dynamic, post-drilling response of crustal microbial ecosystems to changing physical and chemical conditions. Twisted stalks exhibiting a biogenic iron oxyhydroxide signature coated the surface of mineral substrates in the observatories; these are biosignatures indicating colonization by iron oxidizing bacteria during an initial phase of cool, oxic, iron-rich conditions following observatory installation. Following thermal and chemical recovery to warmer, reducing conditions, the in situ microbial structure in the observatory shifted, becoming representative of natural conditions in regional crustal fluids. Firmicutes, metabolic potential of which is unknown but may involve N or S cycling, dominated the post-rebound bacterial community. The archaeal community exhibited an extremely low diversity. Our experiment documented in situ conditions within a natural hydrological system that can pervade over millennia, exemplifying the power of observatory experiments for exploring the subsurface basaltic biosphere, the largest but most poorly understood biotope on Earth. The ISME Journal (2011) 5, 692-703; doi:10.1038/ismej.2010.157; published online 25 November 2010