Carbon comes in handy in producing fuel!

A soil bacterium called Ralstonia eutropha has a natural tendency, whenever it is stressed, to stop growing and put all its energy into making complex carbon compounds. Now scientists at MIT have learnt a trick by which they have fooled the bacteria into making fuel instead.

They've tinkered with its genes to persuade it to make fuel -- specifically, a kind of alcohol called isobutanol that can be directly substituted for, or blended with, gasoline. In its natural state, when the microbe's source of essential nutrients (such as nitrate or phosphate) is restricted, it will go into carbon-storage mode, essentially storing away food for later use when it senses that resources are limited.

What it does is take whatever carbon is available, and store it in the form of a polymer, which is similar in its properties to a lot of petroleum-based plastics. By knocking out a few genes, inserting a gene from another organism, and tinkering with the expression of other genes, the team of scientists were able to redirect the microbe to make fuel instead of plastic.

While the team is focusing on getting the microbe to use CO2 as a carbon source, with slightly different modifications the same microbe could also potentially turn almost any source of carbon, including agricultural waste or municipal waste, into useful fuel!

The team has demonstrated success in modifying the microbe's genes so that it converts carbon into isobutanol in an ongoing process. In continuous culture, substantial amounts of isobutanol was obtained. Now, the researchers are focusing on finding ways to optimize the system to increase the rate of production and to design bioreactors to scale the process up to industrial levels.

That's something -- getting the oldest (and original) inhabitants of the planet to spin gold from straw, no fairy tale! In this case, the straw was making things too hot for the planet!