Thermotolerance in Saccharomyces cerevisiae is linked to resistance to anhydrobiosis

• New approach to study the mechanisms of anhydrobiosis in yeasts.
• Comparison of main characteristics of mesophilic and thermotolerant yeast strains.
• Thermotolerance in yeast correlates with their resistance to anhydrobiosis.
• Thermotolerant yeast is resistant to dehydration also in the exponential growth phase.
• Indication of industrial strains suitable for the production of dry active yeast preparations.

We have demonstrated that a thermotolerant yeast strain (Saccharomyces cerevisiae TS1) is much more resistant to dehydration–rehydration treatments than a mesophilic strain of S. cerevisiae. Yeast resistance to dehydration–rehydration was found to be similar in cells from exponential and stationary growth phases. Under controlled rehydration conditions involving gradual rehydration in water vapour, yeast cell viability was maintained at 90–95%. When S. cerevisiae TS1 cells were pre-grown at 37 °C and then dried, controlled rehydration lead to restoration of plasma membrane integrity, indicating important differences in cell envelope architechture of mesophilic and thermotolerant yeast strains. Comparison of such strains provides new insight into anhydrobiosis in eukaryotic cells.