Increase ethyl acetate production in Saccharomyces cerevisiae by genetic engineering of ethyl acetate metabolic pathway

Ethyl acetate has attracted much attention as an important chemical raw material and a flavor component of alcoholic beverages. In this study, the biosynthetic pathway for the production of ethyl acetate in Chinese liquor yeast was unblocked. In addition to engineering Saccharomyces cerevisiae to increased intracellular CoA and acetyl-CoA levels, we also increased the combining efficiency of acetyl-CoA to ethanol. The genes encoding phosphopantothenate-cysteine ligase, acetyl-CoA synthetase, and alcohol acetyltransferase were overexpressed by inserting the strong promoter PGK1p and the terminator PGK1t, respectively, and then combine them. Our results finally showed that the ethyl acetate levels of all engineering strains were improved. The final engineering strain CLy12a-ATF1-ACS2-CAB2 had a significant increase in ethyl acetate yield, reaching 610.26 (± 14.28) mg/L, and the yield of higher alcohols was significantly decreased. It is proved that the modification of ethyl acetate metabolic pathway is extremely important for the production of ethyl acetate from Saccharomyces cerevisiae.