L-Alanine as an end product of glycolysis in Saccharomyces cerevisiae growing under different hypoxic conditions.

Saccharomyces cerevisiae growing under anaerobic or other hypoxic conditions releases L-alanine into the culture medium as an end product of glycolysis. Although the production of alanine is not as high as that of other fermentation products (ethanol, glycerol, succinic acid), consideration of the pathways leading to alanine in fermenting yeasts indicates that the release of alanine is advantageous to the cellular economy and may be considered as a safety device for excreting reducing equivalents derived from NADPH. No significant changes in the activity of alanine aminotransferase are found in the yeast when grown under different conditions.