Researchers from UCLA reported that they have re-engineered a common bacteria to produce complex and energy-dense alcohols. They have used the bacteria Escherichia coli to produce various long-chain alcohols with carbon numbers ranging from 5 to 8. Higher carbon alcohols are attractive biofuel targets because they have higher energy density and lower water solubility.

The team housed at the University of California Los Angeles and headed by James Liao, has harnessed e. coli’s particularly active enzymatic production system and inserted some chromosomes into the bacteria’s DNA to make longer and longer chains of alcohols. The result is that the modified e. coli can now produce complex and energy dense alcohols of 8 carbons in length.

Nature uses a limited set of metabolites such as organic acids, amino acids, nucleotides, lipids and sugars as building blocks for biosynthesis. These chemicals support the biological functions of all organisms. So far, construction of artificial biological systems is limited by the existing metabolic capabilities. By supplying living cells with chemically synthesized nonnatural amino acids and sugars as new building blocks, it is possible to introduce novel physical and chemical properties into biological entities.

These efforts raise an interesting question: Can we rewire metabolism in a bottom-up fashion to produce nonnatural metabolites from simple carbon source? If so, such engineered artificial metabolism should be able to expand the chemical repertoire that living systems can use and produce. To begin to address this question, we developed a strategy to produce 7-(C7) to 9-carbon (C9) 2-keto acids, which can lead to useful nonnatural alcohols (C6–C8).

—Zhang et al. 2008

The problem with most of these engineered sources is that they must be fed sugar which means they depend on industrial agriculture. Algae on the other hand can and are already being grown on land that is not viable for human food and the left overs after the oil is extracted can be fed to animals and people without processing.

Read more of the details at Greencarcongress.com