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Author Spotlight: Designing Simple and Inexpensive Techniques to Grow Methane-Oxidizing Bacteria in the Laboratory
Published on: September 6, 2024
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Exploring Energy Conservation in Sulphate-Dependent Anaerobic Methane-Oxidising Consortia Through Metabolic Modelling
Gordon Bowman1, Zena Jensvold1, Qusheng Jin1
1Geobiology Group, University of Oregon, Eugene, Oregon, USA.
Environmental Microbiology
|July 24, 2025
Summary
Anaerobic oxidation of methane (AOM) coupled with sulphate reduction (SR) is vital for climate regulation. Our model reveals comparable ATP yields but higher energy efficiency in ANME over SRB, crucial for understanding methane mitigation.
Area of Science:
- Microbial Ecology
- Biogeochemistry
- Biophysics
Background:
- Anaerobic oxidation of methane (AOM) coupled with sulphate reduction (SR) is a key microbial process mitigating methane emissions.
- The bioenergetics and energy conservation mechanisms of AOM-SR consortia are not well understood.
Purpose of the Study:
- To develop a metabolic model quantifying energy fluxes and conservation in AOM-SR consortia.
- To mechanistically predict ATP yields and energy efficiencies without artificial constraints.
Main Methods:
- Integration of enzyme-level thermodynamics and kinetics into a metabolic model.
- Quantification of energy fluxes, ATP yields, and thermodynamic efficiency.
Main Results:
- Both anaerobic methanotrophic archaea (ANME) and sulphate-reducing bacteria (SRB) achieve similar ATP yields (~0.23-0.24 mol ATP/mol substrate) and high thermodynamic efficiency (~60%).
- ANME demonstrate a higher return on investment (ROI) of 18% compared to SRB's 11% due to more efficient substrate activation.
Conclusions:
- Fundamental bioenergetic constraints govern methane oxidation and SR in anoxic environments.
- The study enhances understanding of microbial regulation of methane fluxes and informs methane mitigation strategies in critical ecosystems.
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