Controlled sampling of ribosomally active protistan diversity in sediment-surface layers identifies putative players in the marine carbon sink.
Controlled sampling of ribosomally active protistan diversity in sediment-surface layers identifies putative players in the marine carbon sink.
复制标题
对沉积物表层中核糖体活性原生生物多样性的受控采样确定了海洋碳汇中的假定参与者。
DOI：
10.1038/s41396-019-0581-y
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Rodríguez-Martínez R
中科院分区：
文献类型：
--
作者：
Rodríguez-Martínez R
海洋沉积物是地球上最大的碳储存库之一，然而驱动这些生态系统的微生物群落，特别是真核生物的特征却很差。在这里，我们报告了一种采样系统的实现，该系统可以将试剂注射到深度沉积物中，从而可以在原位保存RNA。利用回收的RNA模板，我们研究了靠近水/沉积物界面的沉积物中存在的“核糖体活性”真核生物多样性。我们证明，原地保存导致恢复显著改变的群落概况。利用SSU rRNA扩增子测序，我们研究了这些环境中的群落结构，显示出了广泛的多样性和较高的相对丰度，特别是：硅藻、迷路菌和纤毛虫。大量硅藻rRNA分子的鉴定与基于显微镜的研究是一致的，但表明这些藻类也可以作为活性细胞而不是死亡形式输出到沉积物中。我们还观察到许多类群包括或分支接近渗透-腐坏原生生物（例如迷路菌和假真菌），微生物可能对碎屑分解很重要。序列数据还包括丰富的扩增子类型的多样性，这些扩增子类型分支靠近fonticulaslime模型。综上所述，我们的数据确定了真核微生物在海洋碳循环中的其他作用；其中假定的渗透-腐养原生生物代表了上层沉积物层中重要的活性微生物成分。
Marine sediments are one of the largest carbon reservoir on Earth, yet the microbial communities, especially the eukaryotes, that drive these ecosystems are poorly characterised. Here, we report implementation of a sampling system that enables injection of reagents into sediments at depth, allowing for preservation of RNA in situ. Using the RNA templates recovered, we investigate the ‘ribosomally active’ eukaryotic diversity present in sediments close to the water/sediment interface. We demonstrate that in situ preservation leads to recovery of a significantly altered community profile. Using SSU rRNA amplicon sequencing, we investigated the community structure in these environments, demonstrating a wide diversity and high relative abundance of stramenopiles and alveolates, specifically: Bacillariophyta (diatoms), labyrinthulomycetes and ciliates. The identification of abundant diatom rRNA molecules is consistent with microscopy-based studies, but demonstrates that these algae can also be exported to the sediment as active cells as opposed to dead forms. We also observe many groups that include, or branch close to, osmotrophic–saprotrophic protists (e.g. labyrinthulomycetes and Pseudofungi), microbes likely to be important for detrital decomposition. The sequence data also included a diversity of abundant amplicon-types that branch close to theFonticulaslime moulds. Taken together, our data identifies additional roles for eukaryotic microbes in the marine carbon cycle; where putative osmotrophic–saprotrophic protists represent a significant active microbial-constituent of the upper sediment layer.