Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA.
ISME J. 2022 Jul;16(7):1750-1764. doi: 10.1038/s41396-022-01222-x. Epub 2022 Mar 28.
Hydrothermal vents have been key to our understanding of the limits of life, and the metabolic and phylogenetic diversity of thermophilic organisms. Here we used environmental metagenomics combined with analysis of physicochemical data and 16S rRNA gene amplicons to characterize the sediment-hosted microorganisms at the recently discovered Auka vents in the Gulf of California. We recovered 325 metagenome assembled genomes (MAGs) representing 54 phyla, over 30% of those currently known, showing the microbial community in Auka hydrothermal sediments is highly diverse. 16S rRNA gene amplicon screening of 224 sediment samples across the vent field indicates that the MAGs retrieved from a single site are representative of the microbial community in the vent field sediments. Metabolic reconstruction of a vent-specific, deeply branching clade within the Desulfobacterota suggests these organisms metabolize sulfur using novel octaheme cytochrome-c proteins related to hydroxylamine oxidoreductase. Community-wide comparison between Auka MAGs and MAGs from Guaymas Basin revealed a remarkable 20% species-level overlap, suggestive of long-distance species transfer over 400 km and subsequent sediment colonization. Optimal growth temperature prediction on the Auka MAGs, and thousands of reference genomes, shows that thermophily is a trait that has evolved frequently. Taken together, our Auka vent field results offer new perspectives on our understanding of hydrothermal vent microbiology.
热液喷口对于我们理解生命的极限以及嗜热生物的代谢和系统发育多样性至关重要。在这里，我们使用环境宏基因组学结合理化数据和 16S rRNA 基因扩增子分析，对加利福尼亚湾新发现的奥卡喷口的沉积物中栖息的微生物进行了表征。我们共获得了 325 个代表 54 个门的宏基因组组装基因组（MAG），超过了目前已知的 30%，表明奥卡热液沉积物中的微生物群落具有高度的多样性。对 224 个喷口场沉积物样本的 16S rRNA 基因扩增子筛选表明，从单个地点获取的 MAG 可代表喷口场沉积物中的微生物群落。对脱硫杆菌门中一个特定的、分支很深的类群的代谢重建表明，这些生物体使用与羟胺氧化还原酶相关的新型八血红素细胞色素 c 蛋白来代谢硫。奥卡 MAG 与瓜伊马斯盆地 MAG 之间的全社区比较显示出惊人的 20%的种水平重叠，表明在 400 公里以上的远距离物种转移和随后的沉积物定殖。对奥卡 MAG 和数千个参考基因组进行的最佳生长温度预测表明，嗜热性是一种经常进化的特征。总之，我们对奥卡喷口场的研究结果为我们理解热液喷口微生物学提供了新的视角。
