Polyphenol rewiring of the microbiome reduces methane emissions

Area of Science:

• Environmental microbiology
• Biogeochemistry
• Climate change mitigation

Background:

• Microbial methane production contributes significantly to global warming.
• Current methane mitigation strategies lack ecosystem-specific microbiome insights.
• Developing effective inhibitors for methanogens is crucial.

Purpose of the Study:

• To assess the impact of catechin on methane emissions in peatlands.
• To elucidate the microbial pathways involved in catechin degradation.
• To understand how catechin affects methanogen activity.

Main Methods:

• Genome-resolved metatranscriptomics and metabolomics were employed.
• Microcosm experiments were conducted on peatland samples.
• Longitudinal sampling tracked microbial and metabolic changes over 35 days.

Main Results:

• Catechin reduced methane emissions by 72-84%.
• A novel catechin degradation pathway involving Actinomycetota, Clostridium, and Pseudomonas_E was identified.
• Catechin treatment decreased gene expression in key methanogen groups and their syntrophic partners.

Conclusions:

• Catechin effectively inhibits methane production by starving hydrogen-utilizing methanogens.
• The identified microbial pathway provides a mechanistic understanding of catechin's action.
• Catechin shows potential for methane mitigation across diverse ecosystems.