Global gene expression analysis of S. cerevisiae strains during sluggish fermentation caused by heat shock

LERENA M.C.; VARGAS A.S.; ALONSO DEL REAL, J.; PEREZ-TORRADO, R.; MERCADO, L.; QUEROL A.; COMBINA M.

Milan

Conferencia; 7th Conference on Physiology of Yeasts and Filamentous Fungi; 2019

European Federation of Biotechnology and Microbial Physiology

Stuck or sluggish fermentations are a frequent issue faced by the winemaking industry. In a previous study we determined that a thermal shock can lead to a problematic fermentation with different intensity according to the temperature applied (36 ºC or 40 ºC) or the yeast strain being used. Also, we identified two S. cerevisiae strains with different behaviour when subjected to heat shock, being SBB11 the most sensitive, and PDM the most resistant. The objective of this study was to evaluate the transcriptomic response of SBB11 and PDM in order to understand their different physiological resistance to heat shock. To that purpose we analysed global gene expression by means of RNAseq analysis for both strains subjected to heat shock. Results showed that the average gene number significantly expressed by both strains was similar when subjected to a heat shock at 36 ºC; whereas at 40ºC PDM expressed a larger number of genes compared to SBB11. Regarding Gene Ontology (GO) at 36 ºC SBB11 up regulates genes of different stress responses pathways, while PDM expresses genes of general metabolic pathways without activation of the stress response. In contrast, at 40 ºC, both strains increase expression of genes involved in stress response and protein folding. However, PDM showed a more robust stress response, as well as genes involved in the autophagic response. On the other hand, SBB11 expresses genes involved in respiration and mitochondrial membrane proteins. Further analysis is needed in order to identify the different physiological mechanisms of heat resistance for these strains.