美国蒙大拿州立大学Roland Hatzenpichler团队近期取得重要工作进展，他们进行了热蛋白菌门甲烷生成菌的培养与可视化研究。相关研究成果2024年7月24日在线发表于《自然》杂志上。

据介绍，甲烷是第二丰富的气候活性气体，了解其来源和汇是微生物学、生物地球化学和气候科学的一项重要工作。几十年来，人们认为甲烷生成，仅限于代谢特化的古菌群，即广古菌。来自不同环境的宏基因组组装基因组中的厌氧烷烃循环标志基因的发现，提出了广古菌外的古菌谱系也参与甲烷生成的假设。

研究人员从一个陆地温泉中培养了隶属于热蛋白菌门（Candidatus Methanosuratincola verstraetei）的菌株LCB70。生长实验结合了活性测定、稳定同位素追踪以及基因组和转录组分析，表明这种嗜热古生菌是通过甲基还原氢营养产甲烷来生长的。冷冻电子断层扫描显示，Ca. M. verstraetei是具有古菌和化学受体阵列的球状细胞，它们可以形成细胞间桥，连接两到三个具有连续细胞质和S层的细胞。

总之，Ca. M. verstraetei的广泛环境分布表明，它们可能在不同缺氧栖息地的碳循环中发挥着重要而迄今为止被忽视的作用。

附：英文原文

Title: Cultivation and visualization of a methanogen of the phylum Thermoproteota

Author: Kohtz, Anthony J., Petrosian, Nikolai, Krukenberg, Viola, Jay, Zackary J., Pilhofer, Martin, Hatzenpichler, Roland

Issue&Volume: 2024-07-24

Abstract: Methane is the second most abundant climate-active gas, and understanding its sources and sinks is an important endeavour in microbiology, biogeochemistry, and climate sciences1,2. For decades, it was thought that methanogenesis, the ability to conserve energy coupled to methane production, was taxonomically restricted to a metabolically specialized group of archaea, the Euryarchaeota1. The discovery of marker genes for anaerobic alkane cycling in metagenome-assembled genomes obtained from diverse habitats has led to the hypothesis that archaeal lineages outside the Euryarchaeota are also involved in methanogenesis3,4,5,6. Here we cultured Candidatus Methanosuratincola verstraetei strain LCB70, a member of the archaeal class Methanomethylicia (formerly Verstraetearchaeota) within the phylum Thermoproteota, from a terrestrial hot spring. Growth experiments combined with activity assays, stable isotope tracing, and genomic and transcriptomic analyses demonstrated that this thermophilic archaeon grows by means of methyl-reducing hydrogenotrophic methanogenesis. Cryo-electron tomography revealed that Ca. M. verstraetei are coccoid cells with archaella and chemoreceptor arrays, and that they can form intercellular bridges connecting two to three cells with continuous cytoplasm and S-layer. The wide environmental distribution of Ca. M. verstraetei suggests that they might play important and hitherto overlooked roles in carbon cycling within diverse anoxic habitats.

DOI: 10.1038/s41586-024-07631-6

Source: https://www.nature.com/articles/s41586-024-07631-6