Deep-Sea Archaea Fix and Share Nitrogen in Methane-Consuming Microbial Consortia
Deep-Sea Archaea Fix and Share Nitrogen in Methane-Consuming Microbial Consortia
复制标题
DOI：
10.1126/science.1178223
复制
发表时间：
2009-10-16
期刊：
影响因子：
56.9
通讯作者：
Orphan, Victoria J.
中科院分区：
文献类型：
--
作者：
Dekas, Anne E.;Poretsky, Rachel S.;Orphan, Victoria J.
固氮（固氮）微生物调节生产力在不同的生态系统，然而，固氮生物的身份是未知的，在许多海洋环境。使用单细胞分辨率纳米二次离子质谱图像（15）N掺入，我们表明，深海厌氧甲烷氧化古菌固定N（2），以及结构相似的CN（-），并与硫酸盐还原细菌共生体共享的产品。这些古菌/细菌联合体已经被认为是底栖生态系统中甲烷的主要汇，我们现在也将它们确定为生物可利用氮的来源。古细菌在固定N（2）的同时保持其甲烷氧化速率，但减少其生长，可能是为了补偿固氮的能量负担。这一发现扩展了能够为N（2）固定提供燃料的呼吸能量的下限，并揭示了全球碳，氮和硫循环之间的联系。
Nitrogen-fixing (diazotrophic) microorganisms regulate productivity in diverse ecosystems; however, the identities of diazotrophs are unknown in many oceanic environments. Using single-cell-resolution nanometer secondary ion mass spectrometry images of (15)N incorporation, we showed that deep-sea anaerobic methane-oxidizing archaea fix N(2), as well as structurally similar CN(-), and share the products with sulfate-reducing bacterial symbionts. These archaeal/bacterial consortia are already recognized as the major sink of methane in benthic ecosystems, and we now identify them as a source of bioavailable nitrogen as well. The archaea maintain their methane oxidation rates while fixing N(2) but reduce their growth, probably in compensation for the energetic burden of diazotrophy. This finding extends the demonstrated lower limits of respiratory energy capable of fueling N(2) fixation and reveals a link between the global carbon, nitrogen, and sulfur cycles.