P147: Engineering Zymomonas for Hydrocarbon Production

Zymomonas mobilis has been a favorite organism for genetic engineering for efficient conversion of lignocellulosic biomass to ethanol because of its natural tolerance to ethanol and high sugar concentrations, low biomass yield and its ability to grow and ferment under anaerobic conditions. Over the past two decades, we have successfully engineered and developed this organism into an excellent biocatalyst to make ethanol from pretreated corn stover hydrolysates with high solid content. We are now focusing our attention on developing this organism to convert biomass sugars into high-density biofuels such as hydrocarbons and other biofuel precursors that are more compatible with the existing infrastructure. We have introduced and expressed heterologous genes into Z. mobilis in order to channel key intermediates in the terpenoid biosynthetic pathway, dimethylallyl diphosphate and farnesyl diphosphate, toward the production of hydrocarbons. We will report on the expression of these genes, production of terpenes, and will discuss our ongoing work on pathway and metabolic engineering for more efficient hydrocarbon production.