C4-C9 Alcohols Production By ‘+1’ Pathway Engineered E.coli: Evaluation of Vector Expression Systems and Fermentation Process Conditions

C4-C9 alcohols have a wide range of uses including fuels, lubricant additives, plasticizers, corrosion inhibitors and are also precursors to other important chemicals. The traditional linear alpha oligomerization process using petrochemical raw materials to produce C4-C9 alcohols is not selective leading to high costs and low-value byproducts. Recent advances in strain engineering technologies provide an opportunity for development of a bioprocess to selectively produce these medium chain length alcohols. The Dow Chemical Company has developed novel enzymes and micro-organisms for selective production of these alcohols using a ‘+1’ pathway. Initial studies revealed that pathway performance was highly sensitive to the design of the expression system. Additional fermentation process optimization studies revealed that process conditions such as pH, induction temperature and substrate feeding also impact the overall alcohol production.