6533b7d2fe1ef96bd125f165

RESEARCH PRODUCT

Functional exploration of the stress response in microorganisms of technological interest : dynamics of membrane response after an ethanol shock in Saccharomyces cerevisiae

Quoc-bao Vo-van

subject

[SDV.AEN] Life Sciences [q-bio]/Food and NutritionStress éthanolMembrane permeability and fluidityOxidative stressErgosterolStress oxydatifSaccharomyces cerevisiaeEthanol stressErgostérolPerméabilité et fluidité membranaire

description

The study of membrane response induced by ethanol stress in Saccharomyces cerevisiae aims to understand mechanisms involved in the survival of eukaryotic cells submitted to high ethanol concentrations. The cell membrane by its position between the intra- and extracellular environment is the first target of ethanolic perturbations. Experiments performed in this study aimed to characterize the maintain of the functional integrity of the membrane in relation to the sterol composition in the yeast S. cerevisiae submitted to different types of ethanolic disturbances: increasing concentrations of ethanol in the growth medium; ethanolic shocks of increasing magnitude; shock 20% ethanol for 15 minutes and then return in a medium without ethanol ("pulse" 20% ethanol)). Our results demonstrate the importance of ergosterol in maintaining membrane integrity and also support the hypothesis of the vector role of ethanol in cell oxidation, whose effectiveness is dependent on the nature of sterols at the membrane level. In addition, our results analyzing the kinetics of transcription of genes involved in oxidative stress response suggest an increased formation of reactive oxygen species (ROS) induced by ethanol in the Δerg6 mutant, affected in the biosynthetic pathway of ergosterol.

https://theses.hal.science/tel-01303137