Engineering Zymomonas Mobilis for the Production of Biofuels and Value-Added Chemicals

Microbial conversion of abundant and sustainable lignocellulosic biomass to biofuels and chemicals offers the opportunity to reduce our current dependence on fossil fuels and chemicals. Known for its high specific glucose uptake rate, rapid catabolism and high ethanol yield, Zymomonas mobilis has been engineered to also efficiently convert the second and third most abundant plant derived sugars, xylose and arabinose, to ethanol at high yield. More recently, we have been applying systems biology and genomic tools to investigate and improve its tolerance to the specific inhibitors present in biomass hydrolysate obtained from dilute acid pretreatment. Z. mobilis is one of the top fermentation organisms currently developed for the cellulosic biomass to ethanol conversion process. With its capabilities for utilizing the vast majority of the biomass sugars in a toxic hydrolysate environment, we asked a question - Can we redirect carbon to make other fuel molecules or chemicals in addition to ethanol by applying metabolic engineering and synthetic biology tools?  Our recent successes in engineering Z. mobilis for the production of value-added chemicals including 2,3 butanediol demonstrated a promising novel platform for future biorefineries.   2,3 Butanediol is a valuable bulk chemical building block which can be used for synthesis of polymers and can be also upgraded in high yields to gasoline, diesel, and jet fuel.