Over the past decade, environmental metagenomics and PCR-based marker gene surveys have revealed that several lineages beyond just a few well-established groups within the Euryarchaeota superphylum harbor the genetic potential for methanogenesis. One of these groups are the Archaeoglobi, a class of thermophilic euryarchaeotes that have long been considered to live non-methanogenic lifestyles. Here, we enriched Candidatus Methanoglobus hypatiae, a methanogen affiliated with the family Archaeoglobaceae, from a hot spring in Yellowstone National Park. The enrichment is sediment-free, grows at 64-70 °C and a pH of 7.8, and produces methane from mono-, di-, and tri-methylamine. Ca. M. hypatiae is represented by a 1.62 Mb metagenome-assembled genome with an estimated completeness of 100% and accounts for up to 67% of cells in the culture according to fluorescence in situ hybridization. Via genome-resolved metatranscriptomics and stable isotope tracing, we demonstrate that Ca. M. hypatiae expresses methylotrophic methanogenesis and energy-conserving pathways for reducing monomethylamine to methane. The detection of Archaeoglobi populations related to Ca. M. hypatiae in 36 geochemically diverse geothermal sites within Yellowstone National Park, as revealed through the examination of previously published gene amplicon datasets, implies a previously underestimated contribution to anaerobic carbon cycling in extreme ecosystems.

中文翻译：

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Ca 培养揭示了古球菌中的甲基营养产甲烷作用。来自黄石温泉的 Methanoglobus hypatiae

在过去的十年中，环境宏基因组学和基于 PCR 的标记基因调查表明，除了广古菌超门中几个成熟的群体之外，还有几个谱系具有产甲烷的遗传潜力。其中一个群体是古球菌，一类嗜热广古菌，长期以来一直被认为过着非产甲烷的生活方式。在这里，我们从黄石国家公园的温泉中富集了 Candidatus Methanoglobus hypatiae，这是一种属于古菌科的产甲烷菌。该浓缩物无沉积物，生长温度为 64-70 °C，pH 值为 7.8，并由单甲胺、二甲胺和三甲胺产生甲烷。约。M. hypatiae 由 1.62 Mb 宏基因组组装的基因组代表，估计完整性为 100%，根据荧光原位杂交，占培养物中细胞的高达 67%。通过基因组解析的宏转录组学和稳定同位素追踪，我们证明了 Ca。M. hypatiae 表达甲基营养型产甲烷作用和将一甲胺还原为甲烷的节能途径。与 Ca 相关的古球菌种群的检测。通过检查之前发布的基因扩增子数据集发现，黄石国家公园内 36 个地球化学多样化的地热地点中存在 M. hypatiae，这意味着之前低估了极端生态系统中厌氧碳循环的贡献。