YEAST SPORULATION INDUCED BY LYSINE DURING GROWTH IN NUTRITION-RICH CONDITIONS

Sporulation of the yeast Saccharomyces cerevisiae 4011 and other strai ns of S. cerevisiae was induced by D- or L-lysine during growth in a n utrient-rich medium. Potassium acetate was not required for the sporul ation. The effects of other D- or L-amino acids on sporulation, if any , were negligible or very slight. Although the sporulation efficiency varied depending on the yeast strain, lysine concentration, pH of the medium and incubation period, the results obtained indicated that nutr itional starvation is not a prerequisite for the sporulation of yeast cells, and that lysine or a certain cellular molecule involved in the metabolism of the amino acid has the ability to cause meiosis and spor ulation in yeast cells.