Chapter 65 : . . . And Yeasts Are Versatile

Abstract:

Saccharomyces cerevisiae and other yeasts, which already generate 24 billion liters of the world's alcohol each year, are beginning to make health care products, too. Supplementing Finnish research on the production of type III collagen by Pichia pastoris, this indicated that yeasts can now be harnessed commercially to make collagen for surgical and medical use more efficiently and safely than by existing methods. Researchers in Belgium found that S. cerevisiae cells use a receptor protein with the same structure as that in many mammalian hormone receptors for the detection of glucose. The signal from the receptor is transmitted in the same way, through a G protein that activates adenylate cyclase. The twofold implications of this work were an admirable illustration of the inseparability of pure and applied science and of the coherence of medical and other biological research. Researchers in France constructed strains of S. cerevisiae that produce more glycerol, and less acetic acid, than usual. They believed that yeasts altered in this way might be of considerable value in improving wine quality. The new strains thus generated two to three times as much glycerol as the original strains, and slightly less alcohol. A further advantage of the genetically modified yeasts is that fermentation is more vigorous than before, saving time and thus reducing the costs of the process.