Effect of thiol reagents on extractability of protein from yeast.

The effect of soluble thiol reagents on the extractability of protein from yeast cells was studied. The incubation of yeast cells with dithiothreitol, 2-mercaptoethanol, or monothioglycerol markedly stimulated the release of soluble carbohydrates into the medium. There was a concomitant improvement (over twofold) in the extractability of protein from the yeast cells. The thiol reagents activated the proteolytic enzymes of the yeast cells. Unless inactivated, these enzymes hydrolyze the extracted protein.