Maltotriose metabolism by Saccharomyces cerevisiae

Saccharomyces cerevisiae grew slower but reached higher cellular densities when grown on 20 g maltotriose l-1 than on the same concentration of glucose or maltose. Antimycin A (3 mg l-1) prevented growth on maltotriose, but not on glucose or maltose, indicating that it is not fermented but is degraded aerobically. This was confirmed by the absence of ethanol and glycerol production. Active uptake of maltotriose across the plasma membrane is the limiting step for metabolism, and the low rate of maltotriose transport observed in maltotriose-grown cells is probably one of the main reasons for the absence of maltotriose fermentation by S. cerevisiae cells.