According to an article in the Science Daily website, researchers have been able to develop a method of producing biofuels by genetically modifying the E. coli bacteria and making it into an efficient biofuel synthesizer.
A team of researchers from UCLA Henry Samueli School of Engineering and Applied Science, made up of professor of chemical and biomolecular engineering James Liao, visiting professor Taizo Hanai and post doctoral fellow Shota Atsumi, modified key pathways in the E. coli bacteria to make them produce higher chain alcohols out of glucose.
Through the team’s efforts, part of the E. coli’s highly active biosynthetic pathway was shifted towards the production of alcohol such as isobutanol, 1-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol and 2-phenylethanol. The new strategy developed has opened up a new method of producing biofuels with the use of bacteria and other microorganisms.
Currently, biofuels are being produced through the processing of agricultural products such as corn and sugarcane. Using current processes, the biofuel ethanol has largely been produced but has been known to be inefficient when mixed with gasoline.
In order to be more efficient, this biofuel may need to be mixed with a gas in order to be used as a transportation fuel. Ethanol also tends to absorb water in its surroundings and may promote corrosion not only in car engines but also in the structures built to store them.
Biofuels produced with higher chain alcohols such as isobutanol provide a better option and may have closer energy densities to that of gasoline. These next generation biofuels are also not as volatile and/or corrosive as ethanol nor do they absorb water as the current biofuel ethanol.
Isobutanol and other C5 alcohols also have higher octane numbers and may also offer less knocking in engines. But current technology has not been able to produce such higher chain alcohols in larger quantities as to make them viable enough to become a gasoline substitute.
The study of using genetically modified E. coli bacteria to produce such higher chain alcohols have provided the viable means from which the next generation of biofuels can be produced commercially in the future. Even the researchers were surprised at the efficiency of the E. coli bacteria was able to synthesize the higher chain alcohols, considering that such microorganisms are not used to or provide any advantage by producing such unusual alcohols.
These alcohols are the typical trace by-products of fermentation. Trying to modify an organism to produce such alcohols usually results in toxicity in the cell. But the surprising success of the study has opened a new avenue where biofuels can be produced through other renewable sources with the use of microorganisms such as E. coli.