Thermokarst (thaw) lakes are projected to be an increasing source of atmospheric methane (CH4), a potent greenhouse gas, as climate warms and permafrost thaws. However, the magnitude of CH4 cycling, ...

Microbial methane utilization (known as methanotrophy) serves as a gatekeeper of methane emissions in numerous ecosystems. Methanotrophy became a plat…

Serpentinization makes H₂- and CH₂-rich fluids analogous to ocean worlds like Enceladus. Isotopes, chemistry, and genomes show methane consumption at pH >11 in Oman—revealing extreme methanotrophy ...

The climate crisis is one of the most imminent threats to humanity and all life on our planet. Methane is not only the second most potent greenhouse gas (GHG) and is responsible for approximately 31% ...

The microbial process of methane oxidation is slow due to energy limitations in environments exposed to low methane concentrations, but understanding limiting factors may help to enhance rates of atmo...

Modification of core carbon and energy metabolism aided a recent evolution of anaerobic methanotrophy in archaea.

Methane oxidation in terrestrial geothermal systems is an understudied process contributing to carbon cycling in extreme environments. We combined geochemica...

Serpentinization makes H₂- and CH₂-rich fluids analogous to ocean worlds like Enceladus. Isotopes, chemistry, and genomes show methane consumption at pH >11 in Oman—revealing extreme methanotrophy ...

Modification of core carbon and energy metabolism aided a recent evolution of anaerobic methanotrophy in archaea.

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Despite their large environmental impact and multiple independent emergences, the processes leading

Freshwater ecosystems represent Earth’s most significant natural methane (CH4) source (117–212 TgCH4·yr−1), surpassing wetland emissions documented in the IPCC Sixth Assessment Report1. CH4 flux is highly sensitive to climate warming, as temperature-driven acceleration of methanogenesis creates a concerning positive feedback loop2,3. Aerobic methanotrophy—the biological oxidation of CH4 to CO2 at the oxic-anoxic interfaces—serves as Earth’s ultimate biogeochemical barrier against aquatic CH4 release, mitigating 10–90% of potential emissions before atmospheric evasion4. While this microbial process provides a critical climate safety valve5, its temperature sensitivity remains inadequately defined across geographic gradients. Current understanding is disproportionately derived from forest soils6 and thermokarst lakes7, leading to a significant knowledge gap given the disproportionate warming rates and CH4 stock vulnerability of freshwater ecosystems. Methane-oxidizing bacteria (MOB) are specialized bacteria that primarily use CH4 as their carbon and energy source under oxic conditions. They initiate the oxidation process by employing particulate or soluble methane monooxygenases (pMMO/sMMO), which are enzymes encoded by the (pmoCAB/mmoBCDXYZ) gene clusters8. Traditionally, MOB were viewed as obligate organisms that relied exclusively on CH4. However, facultative MOB—capable of utilizing multi-carbon compounds or hydrogen—emerged through horizontal gene transfer (HGT) events that acquired membrane transporter genes (facilitator transporters, periplasmic binding proteins) encoding specific substrate transporters...