Regulations and functions of proline utilization in yeast Saccharomyces cerevisiae.

The quality of alcoholic beverages strongly depends on the metabolic characteristics of the yeast cells being used. To control the aroma and taste of alcoholic beverages, as well as the production of ethanol in them, it is thus crucial to select yeast cells with the proper characteristics. Grape must contains a high concentration of proline, an amino acid that can potentially be a useful nitrogen source. However, Saccharomyces cerevisiae cannot utilize proline during the wine-making process, resulting in elevated levels of proline in wine and consequent negative effects on wine quality. In this article, I review and discuss recent discoveries about the inhibitory mechanisms and roles of proline utilization in yeast. The information can help in developing novel yeast strains that can improve fermentation and enhance the quality and production efficiency of wine.