12/28/2009
Newly Engineered Organism Produces High Levels of Isobutanol
Summary
DOE-funded researchers from UCLA and UC Davis have engineered a cyanobacterium, Synechococcus elongatus, to convert carbon dioxide into isobutanol (a good gasoline substitute) and isobutyraldehyde using sunlight. One gene from a bacterium commonly used to make cheese and three genes from two common laboratory bacteria were spliced into S. elongates, enabling it to synthesize these biofuels. The conversion capabilities of the re-engineered microbe compare very favorably with bacterial production of hydrogen and ethanol, and algal production of biodiesel. The “contaminating” isobutyraldehyde has a high vapor pressure and low boiling temperature so it should be possible to remove continuously with minimal energy input during fermentation. It can also be easily converted to isobutanol.
References
Atsumi, S., Higashide, W. & Liao, “Direct photosynthetic recycling of carbon dioxide to isobutyraldehyde,” J.C. Nat Biotechnol. vol 27 December 2009