Eladio Barrio

1 Introduction One key reason for the widespread use of Saccharomyces in fermentation is its remarkable tolerance to relatively high ethanol concentrations. However, ethanol remains a potent stressor, impacting numerous cellular processes; it specifically inhibits respiration, arrests cell growth and can ultimately cause cell death (Alexandre et al. 2001; Stanley et al. 2010; Ma and Liu 2010).

Abstract Ethanol stress poses a considerable challenge for Saccharomyces cerevisiae during fermentation. Strains carrying an extra copy of chromosome III exhibit enhanced ethanol tolerance. Here, we investigated the underlying mechanisms of this tolerance, focusing on gene dosage effects and differential gene expression under ethanol stress. We compared the gene expression profiles of a strain with three copies of chromosome III and its derivative with two copies, exposed to 6% and 10% ethanol.

Abstract Ethanol toxicity is a major challenge for S. cerevisiae during fermentation, affecting its growth and influencing the process. This study investigated the molecular mechanisms of ethanol tolerance using transcriptomic analysis of three S. cerevisiae strains with varying ethanol resistance. We identified distinct responses in membrane lipid synthesis genes, particularly in ergosterol biosynthesis, regulated by the Ino2p transcription factor.