A novel hemiacetal dehydrogenase activity involved in ethyl acetate synthesis in Candida utilis

Acetate ester synthesis was studied in vitro with the ethyl acetate-produci ng yeast Candida utilis. The level of enzyme activity observed for the NAD( +)-dependent hemiacetal dehydrogenase acting on hemiacetal, which was produ ced non-enzymatically from an alcohol and an aldehyde, was much greater tha n that for the other enzyme involved in ester synthesis, alcohol acetyltran sferase. The level of ethyl acetate synthesis in vivo approximately paralle led the hemiacetal dehydrogenase (HADH) activity. The results suggest that the main pathway for ethyl acetate synthesis in C. utilis involves a novel hemiacetal dehydrogenase activity.