SECRETORY EXPRESSION OF HUMAN ALPHA(1)-ANTITRYPSIN IN SACCHAROMYCES-CEREVISIAE USING GALACTOSE AS A GRATUITOUS INDUCER

Human alpha(1)-antitrypsin (alpha(1)-AT) was expressed and secreted in Saccharomyces cerevisiae carrying the gal1 and reg1-501 mutations und er the control of GAL10 promoter. Increasing galactose from 0 to 0.5 g /l increased the extracellular concentration of alpha(1)-AT, though th e secretion efficiency was decreased. The final titre of alpha(1)-AT s ecreted and the secretion efficiency were 17.9 mu g/ml and 24.8%, resp ectively, with 0.5 g galactose/l.