Engineered microbial biofuel production and recovery under supercritical carbon dioxide.

Culture contamination, end-product toxicity, and energy efficient product recovery are long-standing bioprocess challenges. To solve these problems, we propose a high-pressure fermentation strategy, coupled with in situ extraction using the abundant and renewable solvent supercritical carbon dioxide (scCO), which is also known for its broad microbial lethality. Towards this goal, we report the domestication and engineering of a scCO-tolerant strain of Bacillus megaterium, previously isolated from formation waters from the McElmo Dome CO field, to produce branched alcohols that have potential use as biofuels.