近日，美国蒙大拿州立大学教授Roland Hatzenpichler及其课题组研究了高丽菌嗜热培养的甲基还原甲烷生成。这一研究成果于2024年7月24日发表在国际顶尖学术期刊《自然》上。

甲烷是一种强温室气体，而古细菌介导的产甲烷是甲烷的主要来源，对了解地球气候动力学至关重要。最近，在与多个古细菌门相关的宏基因组组装基因组中，发现了编码多种甲烷生成途径的基因。然而，所有关于产甲烷菌的实验研究目前仅限于Euryarchaeota的培养代表。

在该研究中，该课题组人员首次展示了热变形门(TACK超门)中Korarchaeia谱系成员的产甲烷生长。通过对washburnenis候选甲烷脱硫菌LCB3的富集培养，该研究组对代谢活性和同位素示踪剂转化进行了测量，以证明以氢为电子供体的甲醇还原为甲烷。对古菌环基因组和转录组的分析，揭示了与甲烷生成相关的能量守恒途径的独特修饰，包括参与氢和硫代谢的酶复合物。这一新型古菌群的培养和鉴定对于深入评估产甲烷菌的多样性、生理和生物化学至关重要。

附：英文原文

Title: Methyl-reducing methanogenesis by a thermophilic culture of Korarchaeia

Author: Krukenberg, Viola, Kohtz, Anthony J., Jay, Zackary J., Hatzenpichler, Roland

Issue&Volume: 2024-07-24

Abstract: Methanogenesis mediated by archaea is the major source of methane, a strong greenhouse gas, and thus is critical for understanding Earth’s climate dynamics. Recently, genes encoding diverse methanogenesis pathways were discovered in metagenome-assembled genomes affiliated with multiple archaeal phyla1–7. However, all experimental studies on methanogens are currently restricted to cultured representatives of the Euryarchaeota. Here we show for the first time methanogenic growth by a member of the lineage Korarchaeia within the phylum Thermoproteota (TACK superphylum)5–7. Following enrichment cultivation of Candidatus Methanodesulfokora washburnenis strain LCB3 we used measurements of metabolic activity and isotope tracer conversion to demonstrate methanol reduction to methane using hydrogen as electron donor. Analysis of the archaeon’s circular genome and transcriptome revealed unique modifications in the energy conservation pathways linked to methanogenesis, including enzyme complexes involved in hydrogen and sulfur metabolism. The cultivation and characterization of this novel group of archaea is critical for a deeper evaluation of the diversity, physiology, and biochemistry of methanogens.

DOI: 10.1038/s41586-024-07829-8

Source: https://www.nature.com/articles/s41586-024-07829-8