Innovative Genomics Institute, University of California, Berkeley, California, USA.
Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.
Nat Commun. 2024 Jul 31;15(1):6384. doi: 10.1038/s41467-024-49872-z.
The roles of Asgard archaea in eukaryogenesis and marine biogeochemical cycles are well studied, yet their contributions in soil ecosystems remain unknown. Of particular interest are Asgard archaeal contributions to methane cycling in wetland soils. To investigate this, we reconstructed two complete genomes for soil-associated Atabeyarchaeia, a new Asgard lineage, and a complete genome of Freyarchaeia, and predicted their metabolism in situ. Metatranscriptomics reveals expression of genes for [NiFe]-hydrogenases, pyruvate oxidation and carbon fixation via the Wood-Ljungdahl pathway. Also expressed are genes encoding enzymes for amino acid metabolism, anaerobic aldehyde oxidation, hydrogen peroxide detoxification and carbohydrate breakdown to acetate and formate. Overall, soil-associated Asgard archaea are predicted to include non-methanogenic acetogens, highlighting their potential role in carbon cycling in terrestrial environments.
研究表明，古菌门 Asgard 在真核生物起源和海洋生物地球化学循环中发挥了重要作用，但它们在土壤生态系统中的贡献仍不清楚。特别值得关注的是，Asgard 古菌在湿地土壤甲烷循环中的作用。为了研究这一点，我们重建了与土壤相关的 Atabeyarchaeia（一个新的 Asgard 谱系）的两个完整基因组，以及 Freyarchaeia 的完整基因组，并预测了它们在原位的代谢情况。代谢组学揭示了 [NiFe]-氢化酶、丙酮酸氧化和通过 Wood-Ljungdahl 途径固定碳的基因表达。还表达了编码氨基酸代谢、厌氧醛氧化、过氧化氢解毒和碳水化合物分解为乙酸和甲酸盐的酶的基因。总的来说，与土壤相关的 Asgard 古菌预计包括非产甲烷的乙酸生成菌，这突出了它们在陆地环境碳循环中的潜在作用。
