Significant rates of atmospheric hydrogen (H₂) consumption have been observed in temperate soils due to the activity of high-affinity enzymes, such as the group 1h [NiFe]-hydrogenase. We designed broadly inclusive primers targeting the large subunit gene (hhyL) of group 1h [NiFe]-hydrogenases for long-read sequencing to explore its taxonomic distribution across soils. This approach revealed a diverse collection of microorganisms harboring hhyL, including previously unknown groups and taxonomically not assignable sequences. Acidobacterial group 1h [NiFe]-hydrogenase genes were abundant and expressed in temperate soils. To support the participation of acidobacteria in H₂ consumption, we studied two representative mesophilic soil acidobacteria, which expressed group 1h [NiFe]-hydrogenases and consumed atmospheric H₂ during carbon starvation. This is the first time mesophilic acidobacteria, which are abundant in ubiquitous temperate soils, have been shown to oxidize H₂ down to below atmospheric concentrations. As this physiology allows bacteria to survive periods of carbon starvation, it could explain the success of soil acidobacteria. With our long-read sequencing approach of group 1h [NiFe]-hydrogenase genes, we show that the ability to oxidize atmospheric levels of H₂ is more widely distributed among soil bacteria than previously recognized and could represent a common mechanism enabling bacteria to persist during periods of carbon deprivation.

由于高亲和力酶（例如1h [NiFe]-加氢酶）的活性，在温带土壤中已观察到大气中氢气（H ₂）的大量消耗。我们设计了针对1h组[NiFe]-氢化酶的大亚基基因（hhyL）的广泛引物，用于长时间阅读测序，以探索其在土壤中的分类学分布。这种方法揭示了包含hhyL的多种微生物，包括以前未知的组和分类学上不可分配的序列。酸性细菌1h [NiFe]-加氢酶基因丰富并在温带土壤中表达。支持酸性细菌参与H ₂我们研究了两种典型的嗜温土壤酸性细菌的消耗，它们表达1h [NiFe]-加氢酶并在碳饥饿期间消耗了大气中的H ₂。这是首次在普遍的温带土壤中富集的嗜温酸性细菌可将H ₂氧化至低于大气浓度。由于这种生理学使细菌能够在碳饥饿时期中生存，因此可以解释土壤酸性细菌的成功。通过我们对1h [NiFe]-加氢酶基因的长期测序方法，我们证明了氧化大气中H _2的能力 在土壤细菌中的分布比以前认为的要广泛，并且可以代表使细菌在碳缺乏期持续存在的常见机制。