CHICAGO (AFP) — US researcher have engineered a synthetic version of the common e. coli bacteria that could help build a better biofuel, according to a study published Monday.
By altering the basic genetic structure of the bacteria, researchers were able to stimulate it to produce long-chain alcohols that are denser in energy than those found in nature.
Ethanol, one of the leading sources of biofuel, contains just two carbon atoms, and the most common naturally-produced long-chain alcohols contain no more than five carbon atoms.
But alcohols produced for the e. coli study by the University of California's Los Angeles lab contain up to eight carbon atoms, which means they pack a lot more energy.
These long-chain alcohols are also relatively easy to separate from water, making them ideal biofuels.
"Longer chain alcohol has several advantages," said lead researcher James Liao. "It packs more energy per gallon, doesn't corrode the engine and it's more compatible with jet fuel or diesel fuel."
This is the first time researchers have been able to synthesize long-chain alcohol.
Liao's team did so by inserting chromosomes into the e. coli's DNA, which enabled it to overproduce a natural, elongated version of a compound that becomes an amino acid.
Two additional genes on the chromosomes encoded enzymes that converted the elongated compound to a six-carbon alcohol.
"The next step is to develop it in large enough compound quantities and then hand it over to a company for development," Liao told AFP.
"It's not trivial ... we need to optimize the pathway, optimize the process and optimize the conditions."
However, the results do show promise for producing a number of different long-chain alcohols, he said.
The study was published in the Proceedings of the National Academy of Sciences.
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