FIG. 1.

Glycerol and ethanol production by S. cerevisiae strains overexpressing GPD1 on MS medium. The fermentation of wild-type (□) and engineered strains (■) was performed on MS medium in 1.2-liter fermentors at 28°C with agitation with commercial wine yeast strains (A and C) and nonindustrial yeast strains (B and D). Wine yeast strains and laboratory strains (L1, L2) were transformed by the pVT100-U-ZEO-GPD1 plasmid. The V5 GPD1 strain contains the pVT100-U-GPD1 plasmid (23). The strain V5 GPD1L (V5L) contains the pVT100-U-ZEO-GPD1 ΔURA3 plasmid. Glycerol and ethanol were determined after complete sugar exhaustion, except for L1 and L2 strains, which were unable to complete fermentation. The residual sugar content in the corresponding fermented medium was 35 and 9 g/liter (L1 and L1 GPD1) and 0.6 and 30 g/liter (L2 and L2 GPD1).