Halophilic Anaerobic Cultures Enriched with CO₂:H₂ from Different Saline Environments Reveal Unknown Autotrophic Bacterial Diversity and Modular Carbon Fixation Pathways.

ABSTRACT: The subsurface sediments of saline-aquatic systems host diverse microbes, with unclear ecological roles and challenging lab cultivability. Chemolithotrophic anaerobes involved in CO₂-fixation are one of the poorly studied groups. This study focused on understanding these bacteria from subsurface sediments of four representative saline environments, two marine (i.e., Coastal Arabian and Bay of Bengal seas) and two lake (Sambhar and Lonar) systems through enrichment and metagenomics. Enrichment cultures with bicarbonate/CO₂ and hydrogen as the carbon and energy sources, respectively, showed CO₂ fixation, producing acetic and formic acids as the major organic products. Enriched culture with Sambhar Lake sediment produced more formic acid (391 ± 8 mg/L) than ac

SUBMITTER: Kiran R 

PROVIDER: S-EPMC12855331 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature