我国农业领域再发Nature

2024年7月24日，农业农村部沼气科学研究所厌氧微生物创新团队联合荷兰瓦赫宁根大学等多家单位，发现并分离培养了一株非广古菌门的新型产甲烷古菌。相关研究成果发表在《自然（Nature）》。农业农村部成都沼气科学研究所为本研究第一完成单位。承磊研究员为论文通讯作者，博士生巫可佳和周雷为论文共同第一作者。该研究工作得到国家自然科学基金、中国农业科学院科技创新工程等项目支持。

该研究历时7年，利用自主研发的鸡尾酒分离法，首次分离获得佛斯特拉门古菌纯培养物（Methanosuratincola petrocarbonis LWZ-6）。通过碳13同位素标记、模拟培养、膜脂分析等方法，证实了该古菌具有氢依赖代谢甲基类物质产甲烷的生理功能，但不具有发酵生长能力。该研究发现的新型产甲烷古菌，将为研究全球碳循环机理和低碳技术研发提供新型生物资源基础，是我国在厌氧古菌资源领域的一个重大发现和突破。

佛斯特拉门古菌 。受访者供图

Abstract

Methanogenic archaea are main contributors to methane emissions, and have a crucial role in carbon cycling and global warming. Until recently, methanogens were confined to Euryarchaeota, but metagenomic studies revealed the presence of genes encoding the methyl coenzyme M reductase complex in other archaeal clades1,2,3,4, thereby opening up the premise that methanogenesis is taxonomically more widespread. Nevertheless, laboratory cultivation of these non-euryarchaeal methanogens was lacking to corroborate their potential methanogenic ability and physiology. Here we report the isolation of a thermophilic archaeon LWZ-6 from an oil field. This archaeon belongs to the class Methanosuratincolia (originally affiliated with ‘Candidatus Verstraetearchaeota’) in the phylum Thermoproteota. Methanosuratincola petrocarbonis LWZ-6 is a strict hydrogen-dependent methylotrophic methanogen. Although previous metagenomic studies speculated on the fermentative potential of Methanosuratincolia members, strain LWZ-6 does not ferment sugars, peptides or amino acids. Its energy metabolism is linked only to methanogenesis, with methanol and monomethylamine as electron acceptors and hydrogen as an electron donor. Comparative (meta)genome analysis confirmed that hydrogen-dependent methylotrophic methanogenesis is a widespread trait among Methanosuratincolia. Our findings confirm that the diversity of methanogens expands beyond the classical Euryarchaeota and imply the importance of hydrogen-dependent methylotrophic methanogenesis in global methane emissions and carbon cycle.