Deep-sea Microbial Genomics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hai Nan, People's Republic of China.
Key Laboratory for Experimental Study under Deep-sea Extreme Conditions, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hai Nan, People's Republic of China.
Environ Microbiol. 2019 Nov;21(11):4092-4108. doi: 10.1111/1462-2920.14759. Epub 2019 Aug 11.
The low temperature and elevated hydrostatic pressure in hadal trenches at water depths below 6000 m render sample collection difficult. Here, in situ hadal water microbial samples were collected from the Mariana Trench and analysed. The hadal microbial communities at different depths were revealed to be consistent and were dominated by heterotrophic Marinimicrobia. Thirty high-quality metagenome-assembled genomes (MAGs) were retrieved to represent the major hadal microbes affiliated with 12 prokaryotic phyla. Most of the MAGs were newly reported and probably derived from novel hadal inhabitants as exemplified by a potentially new candidate archaeal phylum in the DPANN superphylum. Metabolic reconstruction indicated that a great number of the MAGs participated in nitrogen and sulfur cycling, in which the nitrification process was driven sequentially by Thaumarchaeota and Nitrospirae and sulfur oxidization by Rhodospirillales in the Alphaproteobacteria class. Moreover, several groups of hadal microbes were revealed to be potential carbon monoxide oxidizers. Metatranscriptomic result highlighted the contribution of Chloroflexi in degrading recalcitrant dissolved organic matter and Marinimicrobia in extracellular protein decomposition. The present work provides an in-depth view on the hadal microbial communities regarding their endemism and element cycles.
在水深 6000 米以下的海沟中，低温和高压使得样本采集变得困难。本研究从马里亚纳海沟采集了原位深海水微生物样本并进行了分析。结果表明，不同深度的深海微生物群落是一致的，以异养 Marinimicrobia 为主导。共获得了 30 个高质量的宏基因组组装基因组（MAGs），代表了与 12 个原核门相关的主要深海微生物。大多数 MAGs 是新报道的，可能来自新的深海生物，例如 DPANN 超门中的一个潜在新候选古菌门。代谢重建表明，大量的 MAGs参与氮和硫循环，其中硝化过程由 Thaumarchaeota 和 Nitrospirae 依次驱动，在 Alphaproteobacteria 类中硫氧化由 Rhodospirillales 驱动。此外，几组深海微生物被发现可能是一氧化碳的氧化菌。宏转录组结果突出了 Chloroflexi 在降解难降解的溶解有机物质和 Marinimicrobia 在细胞外蛋白分解中的作用。本研究深入了解了深海微生物群落的特有性和元素循环。
