The amyA and glaA genes were subcloned individually and combined in yBBH1-derived plasmids (Figure 1, Table 1) and transformed into the laboratory strain S. cerevisiae Y294. The S. cerevisiae strains expressing α-amylase (AmyA) developed clearing zones on solid SC-URA media containing 2% soluble starch (Figure 2), whilst zones were neither expected nor observed for strains expressing the exo-type glucoamylase. Similar results were obtained when the corresponding plasmids were transformed in S. cerevisiae Mnuα1 strain, a haploid strain derived from the industrial MH1000 strain