BACTERIA which lives in the human gut could hold the key to finding an efficient way to capture and store carbon dioxide, scientists have found.

Cutting carbon dioxide (CO2) emissions to slow down or even reverse global warming is one of the biggest challenges humankind faces.

New ways of capturing and storing CO2 will be needed, and researchers at Dundee University have shown E. coli could play a crucial role.

Professor Frank Sargent and colleagues at the university’s school of life sciences, working with local industry partners Sasol UK and Ingenza Ltd, have developed a process that enables it to act as an efficient carbon capture device.

E. coli is normally harmless to humans but some types can cause infections with life-threatening potential.

Sargent said: “Reducing carbon dioxide emissions will require a basket of different solutions and nature offers some exciting options. Microscopic, single-celled bacteria are used to living in extreme environments and often perform chemical reactions that plants and animals cannot.

“For example, the E. coli bacterium can grow in the complete absence of oxygen. When it does this, it makes a special metal-containing enzyme, called FHL, which can interconvert gaseous carbon dioxide with liquid formic acid.

“This could provide an opportunity to capture carbon dioxide into a manageable product that is easily stored, controlled or even used to make other things. The trouble is, the normal conversion process is slow and sometimes unreliable. What we have done is develop a process that enables the bacterium to operate as a very efficient biological carbon capture device. When the bacteria containing the FHL enzyme are placed under pressurised carbon dioxide and hydrogen gas mixtures, 100 per cent conversion of the carbon dioxide to formic acid is observed. The reaction happens quickly, over a few hours, and at ambient temperatures.

“This could be an important breakthrough in biotechnology. It should be possible to optimise the system still further and finally develop a ‘microbial cell factory’ that could be used to mop up carbon dioxide from many different types of industry.

“Not all bacteria are bad. Some might even save the planet.”

The results of the research, funded by the Biotechnology and Biological Sciences Research Council, are published in the journal Current Biology.