Effect of YDL080C and LEU2 gene knockout on isoamyl alcohol production in industrial yellow rice wine yeast

The production of isoamyl alcohol,was studied in industrial rice wine yeast N85 with the method of gene knockout.Disruption cassette of “ YDL080C- URA3- YDL080 C ”and “ LEU2- URA3- LEU2 ”were constructed using fusion PCR,and then electro- transformed into the Δura3 haploid yeast strain( MATa ura3),respectively.Finally the engineered haploids Na- y and Na- l were obtained. Lab- scale fermentation of yellow rice wine was preceded with Na- y and Na- l,respectively. The results showed that the concentration of isoamyl alcohol was almost invariable between the engineered strain Na- y and the parental haploid. On the contrary,the content of isoamyl alcohol was reduced by 16.16% with the engineered strain Na- l.There was no difference in physical and chemical indexes between the engineered strain and parental strain.