E. coli bacteria 'can produce diesel biofuel.

A strain of bacteria has been created that can produce fuel, scientists say.

Researchers genetically modified E. coli bacteria to convert sugar into an oil that is almost identical to conventional diesel.

If the process could be scaled up, this synthetic fuel could be a viable alternative to the fossil fuel, the team said.

The study is published in the Proceedings of the National Academy of Sciences.

Professor John Love, a synthetic biologist from the University of Exeter, said: "Rather than making a replacement fuel like some biofuels, we have made a substitute fossil fuel.

"The idea is that car manufacturers, consumers and fuel retailers wouldn't even notice the difference - it would just become another part of the fuel production chain."

Fuel factories

There is a push to increase the use of biofuels around the world.

In the European Union, a 10% target for the use of these crop-based fuels in the transport sector has been set for 2020.

But most forms of biodiesel and bioethanol that are currently used are not fully compatible with modern engines. Fractions of the substances (between 5-10%) need to be blended with petroleum before they can be used in most engines. However, the fuel produced by the modified E. coli bacteria is different. Prof Love explained: "What we've done is produced fuels that are exactly the chain length required for the modern engine and exactly the composition that is required.

"They are bio-fossil-fuels if you like."

To create the fuel, the researchers, who were funded by the oil company Shell and the Biotechnology and Biological Sciences Research Council, used a strain of E. coli that usually takes in sugar and then turns it into fat.

Using synthetic biology, the team altered the bacteria's cell mechanisms so that the sugar was converted to synthetic fuel molecules instead.

By altering the bacteria's genes, they were able to transform the bugs into fuel-producing factories....