Regulation of Saccharomyces cerevisiae genetic engineering on the production of acetate esters and higher alcohols during Chinese Baijiu fermentation

Abstract

Acetate esters and higher alcohols greatly influence the quality and flavor profiles of Chinese Baijiu (Chinese liquor). Various mutants have been constructed to investigate the interactions of ATF1 overexpression, IAH1 deletion, and BAT2 deletion on the production of acetate esters and higher alcohols. The results showed that the overexpression of ATF1 under the control of the PGK1 promoter with BAT2 and IAH1 double-gene deletion led to a higher production of acetate esters and a lower production of higher alcohols than the overexpression of ATF1 with IAH1 deletion or overexpression of ATF1 with BAT2 deletion. Moreover, deletion of IAH1 in ATF1 overexpression strains effectively increased the production of isobutyl acetate and isoamyl acetate by reducing the hydrolysis of acetate esters. The decline in the production of higher alcohol by the ATF1 overexpression strains with BAT2 deletion is due to the interaction of ATF1 overexpression and BAT2 deletion. Mutants with varying abilities of producing acetate esters and higher alcohols were developed by genetic engineering. These strains have great potential for industrial application.