Physiological and transcriptional responses to high concentrations of lactic acid in anaerobic chemostat cultures of Saccharomyces cerevisiae.

ABSTRACT: Based on the high acid tolerance and the simple nutritional requirements of Saccharomyces cerevisiae, engineered strains of this yeast are considered biocatalysts for industrial production of high-purity undissociated lactic acid. However, high concentrations of lactic acid are toxic to S. cerevisiae, thus limiting its growth and product formation. Physiological and transcriptional responses to high concentrations of lactic acid were studied in anaerobic, glucose-limited chemostat cultures grown at different pH values and lactic acid concentrations, resulting in a 50% decrease in the biomass yield. At pH 5, the yield decrease was caused mostly by osmotically induced glycerol production and not by the classic weak-acid action, as was observed at pH 3. Cultures grown at pH 5 with 900 mM lact

SUBMITTER: Abbott DA 

PROVIDER: S-EPMC2547041 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature