Response of Saccharomyces cerevisiae to stress-free acidification
- 165 Downloads
Genome-wide transcriptional analysis of a Saccharomyces cerevisiae batch culture revealed that more than 829 genes were regulated in response to an environmental shift from pH 6 to pH 3 by added sulfuric acid. This shift in pH was not detrimental to the rate of growth compared to a control culture that was maintained at pH 6 and the transcriptional changes most strikingly implicated not up- but down-regulation of stress responses. In addition, the transcriptional changes upon acid addition indicated remodeling of the cell wall and central carbon metabolish. The overall trend of changes was similar for the pH-shift experiment and the pH 6 control. However, the changes in the pH 6 control were much weaker and occurred 2.5 h later than in the pH-shift experiment. Thus, the reaction to the steep pH decrease was an immediate response within the normal repertoire of adaptation shown in later stages of fermentation at pH 6. Artificially preventing the yeast from acidifying the medium may be considered physiologically stressful under the tested conditions.
Keywordsstress response Saccharomyces cerevisiae acidification fermentation pyruvate decarboxylase
Unable to display preview. Download preview PDF.
- Hatzixanthis, K., M. Mollapour, I. Seymour, B.E. Bauer, G. Krapf, C. Schuller, K. Kuchler, and P.W. Piper. 2003. Moderately lipophilic carboxylate compounds are the selective inducers of the Saccharomyces cerevisiae Pdr12p ATP-binding cassette transporter. Yeast 20, 575–585.PubMedCrossRefGoogle Scholar
- Kawahata, M., K. Masaki, T. Fujii, and H. Iefuji. 2006. Yeast genes involved in response to lactic acid and acetic acid: acidic conditions caused by the organic acids in Saccharomyces cerevisiae cultures induce expression of intracellular metal metabolism genes regulated by Aft1p. FEMS Yeast Res. 6, 924–936.PubMedCrossRefGoogle Scholar