Carbon-monoxide-driven bioethanol production operates through a tungsten-dependent catalyst.

ABSTRACT: Microbial alcohol production from waste gases is a game changer for sustainable carbon cycling and remediation. While the biotechnological process using Clostridium autoethanogenum to transform syngas (H₂, CO₂ and CO) is blooming, scientific debates remain on the ethanol biosynthesis pathway. Here, we experimentally validated that ethanol production is initiated through a tungsten-dependent aldehyde:ferredoxin oxidoreductase (AFOR), which reduces acetate to acetaldehyde. The reaction, thermodynamically unfavorable under standard conditions, has been considered by many as unsuitable in vivo but is rather approved by metabolic modeling. To answer this riddle, we demonstrated that the thermodynamic coupling of CO oxidation and ethanol synthesis allows acetate reduction.

SUBMITTER: Lemaire ON 

PROVIDER: S-EPMC12727526 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature