PT  - JOURNAL ARTICLE
AU  - Ping Chen
AU  - Hui Zhou
AU  - Yanyan Huang
AU  - Zhe Xie
AU  - Mengjie Zhang
AU  - Yuli Wei
AU  - Jia Li
AU  - Yuewei Ma
AU  - Min Luo
AU  - Wenmian Ding
AU  - Junwei Cao
AU  - Tao Jiang
AU  - Peng Nan
AU  - Jiasong Fang
AU  - Xuan Li
TI  - Revealing the full biosphere structure and versatile metabolic functions in the deepest ocean sediment of the Challenger Deep
AID  - 10.1101/2021.06.05.447043
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.06.05.447043
4099  - http://biorxiv.org/content/early/2021/06/06/2021.06.05.447043.short
4100  - http://biorxiv.org/content/early/2021/06/06/2021.06.05.447043.full
AB  - Background The full biosphere structure and functional exploration of the microbial communities of the Challenger Deep of the Mariana Trench, the deepest known hadal zone on Earth, lag far behind that of other marine realms.Results We adopt a deep metagenomics approach to investigate the microbiome in the sediment of Challenger Deep, Mariana Trench. We construct 178 metagenome-assembled genomes (MAGs) representing 26 phyla, 16 of which are reported from hadal sediment for the first time. Based on the MAGs, we find the microbial community functions are marked by enrichment and prevalence of mixotrophy and facultative anaerobic metabolism. The microeukaryotic community is found to be dominated by six fungal groups that are characterized for the first time in hadal sediment to possess the assimilatory and dissimilatory nitrate/sulfate reduction, and hydrogen sulfide oxidation pathways. By metaviromic analysis, we reveal novel hadal Caudovirales clades, distinctive virus-host interactions, and specialized auxiliary metabolic genes for modulating hosts’ nitrogen/sulfur metabolism. The hadal microbiome is further investigated by large-scale cultivation that cataloged 1070 bacterial and 19 fungal isolates from the Challenger Deep sediment, many of which are found to be new species specialized in the hadal habitat.Conclusion Our hadal MAGs and isolates increase the diversity of the Challenger Deep sediment microbial genomes and isolates present in the public. The deep metagenomics approach fills the knowledge gaps in structure and diversity of the hadal microbiome, and provides novel insight into the ecology and metabolism of eukaryotic and viral components in the deepest biosphere on earth.Competing Interest StatementThe authors have declared no competing interest.