The production of biofuels has received increased attention due to world wide energy and environmental concerns.  Longer chain alcohols are attractive as biofuels because their energy densities are comparable to gasoline, they are hydrophobic and are therefore less corrosive, and they can already be used in the existing infrastructure.  Recently, we have demonstrated the production of a novel biofuel, isobutanol, in E. coli by constructing a synthetic pathway that utilizes the organism’s ketoacid pathway.   In addition, we have shown that isobutanol can be produced from glucose to high titer [1].  We have further engineered E. coli as an efficient host to produce isobutanol by identifying and relieving cofactor limitations and by removal of carbon competitive pathways.

1.         Atsumi, S., T. Hanai, and J.C. Liao, Non-fermentative pathways for synthesis of branched-chain higher alcohols as biofuels. Nature, 2008. 451(7174): p. 86-9.