DETERMINATION OF OPTIMAL GLUCOSE-CONCENTRATIONS FOR GLUCOAMYLASE PRODUCTION FROM PLASMID-HARBORING AND CHROMOSOME-INTEGRATED RECOMBINANT YEASTS USING A SUC2 PROMOTER

During foreign protein production using a promoter such as SUC2, which is controllable by the glucose concentration in the culture broth, it is important to determine the optimal glucose concentration for maxim um protein production. The optimal glucose concentrations for maximal production of glucoamylase in plasmid-harboring recombinant yeast MMY2 SUCSTA culture and in chromosome-integrated recombinant yeast MMY2SUCS TA-I culture were 0.13 and 0.09 g litre(-1), respectively. Using gluco se feeding to maintain these optimal glucose concentrations, the extra cellular glucoamylase productivities of fed-batch culture were increas ed (12-fold in MMY2SUCSTA and 23-fold in MMY2SUCSTA-I) over simulation results from batch cultures.