Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Genes (Basel). 2021 Jun 29;12(7):990. doi: 10.3390/genes12070990.
Marine viruses are widely distributed and influence matter and energy transformation in ecosystems by modulating hosts' metabolism. The hadal trenches represent the deepest marine habitat on Earth, for which the viral communities and related biogeochemical functions are least explored and poorly understood. Here, using the sediment samples (8720 m below sea level) collected from the New Britain Trench (NBT), we investigated the viral community, diversity, and genetic potentials in the hadal sediment habitat for the first time by deep shotgun metagenomic sequencing. We found the NBT sediment viral community was dominated by Siphoviridae, Myoviridae, Podoviridae, Mimiviridae, and Phycodnaviridae, which belong to the dsDNA viruses. However, the large majority of them remained uncharacterized. We found the hadal sediment virome had some common components by comparing the hadal sediment viruses with those of hadal aquatic habitats and those of bathypelagic and terrestrial habitats. It was also distinctive in community structure and had many novel viral clusters not associated with the other habitual virome included in our analyses. Further phylogenetic analysis on its Caudovirales showed novel diversities, including new clades specially evolved in the hadal sediment habitat. Annotation of the NBT sediment viruses indicated the viruses might influence microbial hydrocarbon biodegradation and carbon and sulfur cycling via metabolic augmentation through auxiliary metabolic genes (AMGs). Our study filled in the knowledge gaps on the virome of the hadal sediment habitats and provided insight into the evolution and the potential metabolic functions of the hadal sediment virome.
海洋病毒广泛分布，并通过调节宿主代谢来影响生态系统中的物质和能量转化。海沟代表了地球上最深的海洋栖息地，而该栖息地的病毒群落及其相关的生物地球化学功能尚未得到充分探索和理解。在这里，我们首次通过深度 shotgun 宏基因组测序，使用来自新不列颠海沟（NBT）的海底沉积物样本（海平面以下 8720 米），调查了深海沉积物栖息地中的病毒群落、多样性和遗传潜力。我们发现，NBT 沉积物病毒群主要由 Siphoviridae、Myoviridae、Podoviridae、Mimiviridae 和 Phycodnaviridae 组成，它们属于双链 DNA 病毒。然而，其中绝大多数仍未被表征。通过将深海沉积物病毒与深海水生栖息地以及深海和陆地栖息地的病毒进行比较，我们发现深海沉积物病毒组具有一些共同的组成部分。它在群落结构上也具有独特性，并且有许多与我们分析中包含的其他习惯病毒组没有关联的新型病毒簇。对其长尾病毒目进行的进一步系统发育分析显示出了新的多样性，包括在深海沉积物栖息地中专门进化的新分支。对 NBT 沉积物病毒的注释表明，病毒可能通过辅助代谢基因（AMGs）增强代谢来影响微生物烃类生物降解以及碳和硫循环。我们的研究填补了深海沉积物栖息地病毒组的知识空白，并深入了解了深海沉积物病毒组的进化和潜在代谢功能。
