Breakthrough For Converting CO2 Back Into Natural Gas

University of Kent scientists have discovered how bacteria make a component that facilitates converting carbon dioxide (CO2) into methane gas for energy use. Recycling CO2 back into energy has immense potential for making these emissions useful rather than a major factor in global warming.

So far the bacteria called methanogens, that can convert CO2 into methane are notoriously difficult to grow, their use in gas production remains extremely limited.

The methanogen cultivation challenge inspired the team of scientists led by Professor Martin Warren, of the University of Kent’s School of Biosciences, to investigate how a key molecule, coenzyme F430, is made in these bacteria.

Although F430 – the catalyst for the production process – is structurally very similar to the red pigment found in red blood cells (haem) and the green pigment found in plants (chlorophyll), the properties of this bright yellow coenzyme allows methanogenic bacteria to breathe in carbon dioxide and exhale methane.

By understanding how essential components of the methanogenensis process of biological methane production such as coenzyme F430 are made, scientists are one step closer to being able to engineer a more effective and obliging methane-producing bacterium.

The research team has shown that coenzyme F430 is made from the same starting molecular template from which haem and chlorophyll are derived, but uses a different suite of enzymes to convert this starting material into F430. Key to this process is the insertion of a metal ion, which is glued into the center of the coenzyme.

If the methanogenesis process of biological methane production could be engineered into bacteria that are easier to grow, such as the microbe E. coli, then engineered strains could be employed to catch carbon dioxide emissions and convert them into methane for energy production.

The team’s study paper, Elucidation of the biosynthesis of the methane catalyst coenzyme F430 has been published in the journal Nature.

This breakthrough is in reality a discovery of the molecule and its function, not the genetic code the bacteria use to make it. It won’t take long to isolate that. That’s when the genetic engineering gets underway and learning if this molecule alone will produce methane or if more code is needed to get to a scalable type of bacteria.