High-pressure Methanogenesis Reveals Metabolic Adaptation to Dissolved CO₂ Limitation.

ABSTRACT: This study investigated the effects of elevated hydrostatic pressure on methane production and gene expression in a hydrogenotrophic methanogen isolated from subseafloor sediments at biogenic gas hydrate sites, with a focus on the implications of CO₂ availability. Using high-pressure cultivation, the methane production rate decreased by 15% at 25 MPa, while a transcriptomic anal-ysis revealed the marked up-regulation of methyl-coenzyme M reductase and ATP synthase. These results suggest that methanogens compensate for pressure-driven constraints on CO₂ utilization by increasing the expression of key methanogenic enzymes, underscoring the overlooked role of CO₂ in deep biosphere microbial processes.

SUBMITTER: Katayama T 

PROVIDER: S-EPMC12727201 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature