Metabolic potential of microbial communities from ferruginous sediments
Metabolic potential of microbial communities from ferruginous sediments
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DOI：
10.1111/1462-2920.14343
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发表时间：
2018-10
影响因子：
5.1
通讯作者：
A. Vuillemin;F. Horn;A. Friese;M. Winkel;M. Alawi;D. Wagner;C. Henny;W. Orsi;S. Crowe
中科院分区：
文献类型：
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作者：
A. Vuillemin;F. Horn;A. Friese;M. Winkel;M. Alawi;D. Wagner;C. Henny;W. Orsi;S. Crowe
含铁(富铁，贫SO4)的条件通常仅限于今天地球上的淡水沉积物，但很可能在太古宙和元古界都很普遍。印度尼西亚的Towuti湖是一个巨大的含铁湖泊，它可能拥有类似于在含铁太古宙海洋中运行的地球化学过程。微生物群落在这种条件下的代谢潜力和相关的生物地球化学循环在很大程度上仍不清楚。我们将地球化学测量(孔隙水化学、硫酸盐还原速率)与超基因组学相结合，将沉积物上部50厘米的代谢潜力与地球化学过程联系起来。微生物多样性和异化硫酸盐还原(DsrAB)和产甲烷(MCRA)基因的数量随着深度的增加而减少，潜在的硫酸盐还原速率也随着深度的增加而减少。与已知的铁和硫酸盐还原有关的分类群的存在意味着铁和硫酸盐作为电子受体的潜在用途。孔隙水中的醋酸盐浓度表明，发酵产生的醋酸盐很活跃。发酵可能为呼吸作用提供底物，铁和硫酸盐作为电子供体，并在整个核心检测到产甲烷菌。ANME-116S和MCRA基因的存在暗示了甲烷厌氧氧化的可能性。总体而言，我们的数据表明，低氧含铁沉积物中的微生物群落代谢支持Fe、S和C的耦合生物地球化学循环。
Ferruginous (Fe-rich, SO4 -poor) conditions are generally restricted to freshwater sediments on Earth today, but were likely widespread during the Archean and Proterozoic Eons. Lake Towuti, Indonesia, is a large ferruginous lake that likely hosts geochemical processes analogous to those that operated in the ferruginous Archean ocean. The metabolic potential of microbial communities and related biogeochemical cycling under such conditions remain largely unknown. We combined geochemical measurements (pore water chemistry, sulfate reduction rates) with metagenomics to link metabolic potential with geochemical processes in the upper 50 cm of sediment. Microbial diversity and quantities of genes for dissimilatory sulfate reduction (dsrAB) and methanogenesis (mcrA) decrease with increasing depth, as do rates of potential sulfate reduction. The presence of taxa affiliated with known iron- and sulfate-reducers implies potential use of ferric iron and sulfate as electron acceptors. Pore-water concentrations of acetate imply active production through fermentation. Fermentation likely provides substrates for respiration with iron and sulfate as electron donors and for methanogens that were detected throughout the core. The presence of ANME-1 16S and mcrA genes suggests potential for anaerobic methane oxidation. Overall our data suggest that microbial community metabolism in anoxic ferruginous sediments support coupled Fe, S and C biogeochemical cycling.