Biochemists reveal how the Earth produces methane

A team of biochemists from Utah State University have investigated how methane is produced. The experts are challenging a long-held notion that methane is exclusively made by living organisms during a process called methanogenesis.

While most of the focus on harmful greenhouse gases is focused on carbon dioxide (CO2), methane is at least 30 times more potent than CO2 as a heat-trapping gas. The reason more emphasis is usually placed on carbon dioxide emissions compared to methane emissions is because CO2 lingers much longer in the atmosphere.

Methane is the primary component of natural gas, which is a critical source of fuel for cooking, heating, and electricity generation. Because of this, there is widespread interest in how the gas is made.

The results of the study, which also included biochemists from the University of Washington, revealed a bacterial, iron-only nitrogenase pathway for methane formation. The researchers also established that the iron-only variant of nitrogenase can transform carbon dioxide into methane in a single, enzymatic step.

Study co-author Lance Seefeldt is a professor in the Department of Chemistry and Biochemistry at Utah State University.

“Our findings are significant because they give scientists a second target to chase in understanding biological methane formation and rising methane emissions,” said Professor Seefeldt. “In addition, the discovery could drive efforts to turn waste gases into usable fuels.”

The professor said that the ability to accomplish a large-scale transition to clean, alternative fuels will have extensive benefits.

“It’s currently a ‘holy grail’ of energy science,” said Professor Seefeldt. “The knowledge we’re gradually gaining could be used to make fuels from waste gases, helping to improve the environment.”

The study findings are published online in the journal Nature Microbiology.

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By Chrissy Sexton, Earth.com Staff Writer