(615d) Utilizing an Endogenous Pathway for 1-Butanol Production in Saccharomyces Cerevisiae
AIChE Annual Meeting
2014
2014 AIChE Annual Meeting
Food, Pharmaceutical & Bioengineering Division
Biocatalysis and Biosynthesis II: Biofuels and Commodity Chemicals Applications
Thursday, November 20, 2014 - 9:24am to 9:42am
Microbial production of higher alcohols from renewable feedstock has attracted intensive attention owing to its potential as a source for next-generation gasoline substitutes. Here we report the discovery, characterization and engineering of an endogenous 1-butanol pathway in Saccharomyces cerevisiae. Upon introduction of a single gene deletion adh1Δ, S. cerevisiae was able to accumulate more than 120 mg/L 1-butanol from glucose in rich medium. Precursor feeding, 13C-isotope labeling and gene deletion experiments demonstrated that the endogenous 1-butanol production was dependent on catabolism of threonine in a manner similar to fusel alcohol production by the Ehrlich pathway. Specifically, the leucine biosynthesis pathway was engaged in the conversion of key 2-keto acid intermediates. Overexpression of the pathway enzymes and elimination of competing pathways achieved the highest reported 1-butanol titer in S. cerevisiae (243 mg/L).