D he yield is satisfactory, the scientists from the Californian Joint Bioenergy Institute report in the journal 'Nature' (vol. 463, p. 559).
Inexpensive biodiesel from biomass
Eric Steen, Yisheng Kang and their colleagues changed the metabolism of the intestinal bacterium Escherichia coli several times genetically. Fats, which the bacteria normally store, were then combined with self-produced alcohol to form fatty acid methyl esters, i.e. biodiesel. The process worked particularly well with dextrose as bacterial feed.
The genetically modified microorganisms were also able to break down the plant-based building material xylan into individual sugar molecules and metabolize them. The scientists write that this enables a particularly cost-effective production of biodiesel from vegetable biomass.
Biodiesel has so far been made from vegetable oils such as rapeseed oil. However, the cultivation of these plants consumes arable land. So far, this fuel has been in direct competition with food crops such as grain. The researchers therefore see a good alternative in the new process.
The Joint Bioenergy Institute is funded by the United States Department of Energy.