A plasmid containing the glucoamylase cDNA gene (glu) from Aspergillus awamori, a portion of Saccharomyces
cerevisiae ribosomal DNA, S. cerevisiae ura3 gene deficient in promoter, and bacterial cloning vector pSP72 was
constructed for the integration of an A. awamori glu gene into the genome of S. cerevisiae. Several transformants
were able to form halos around colonies on the plate containing 2% soluble starch. This indicated the secretion
of glucoamylase by the yeasts. Glucoamylase production by transformant G23-8 reached 162 U l21
. Southern
hybridization analysis revealed that the plasmid was integrated into the host chromosome in tandem repeat and
dispersion copies. It was estimated that the integrants carried up to 140 glu gene copies per genome. The
integrants were mitotically stable for 50 generations without selective pressure. © 1998 Elsevier Science Inc