Rewired bacteria could make food and fuel production more sustainable Mediscan/Alamy Stock Photo

Bacteria have been rewired to live off carbon dioxide and they could be used to produce biofuels in a more sustainable way.

Specific strains of Escherichia coli bacteria are often used to make biofuels and other chemicals, but they normally feed on sugar. Ron Milo at the Weizmann Institute of Science in Israel and his colleagues have managed to make E. coli consume CO2 instead.

The researchers added genes to the E. coli genome for an enzyme that converts atmospheric CO2 to biomass and deleted genes needed for sugar metabolism. They then left the bacteria for several months in the lab. After 200 days, they found that the microbes had successfully evolved to grow without needing sugar for food.


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Milo says he didn’t expect to be able to make such “drastic changes” to the E. coli’s natural mode of growth.

Currently, the bacteria still emit more CO2 than they consume as part of the growing process, but the researchers think they may be able to reduce this in the future.

Because E. coli is easily manipulated and already widely exploited for biotechnology, the possibilities of using it are “endless”, says Frank Sargent at Newcastle University, UK.

The bacteria could use CO2 generated by the steel or concrete industry to make insulin, for example. “This type of directed evolution is already a Nobel prize-winning type of science and this is a terrific example of why,” says Sargent.

Journal reference: Cell, DOI: 10.1016/j.cell.2019.11.009