Slow heat rate increases yeast thermotolerance by maintaining plasma membrane integrity
✍ Scribed by Iñigo Martínez de Marañón; Nicolas Chaudanson; Nathalie Joly; Patrick Gervais
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 110 KB
- Volume
- 65
- Category
- Article
- ISSN
- 0006-3592
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✦ Synopsis
Thermal resistance of Saccharomyces cerevisiae was found to be drastically dependent on the kinet- ics of heat perturbation. Yeasts were found to be more resistant to a plateau of 1 h at 50°C after a slope of temperature increase (slow and linear temperature increments) than after a shock (sudden temperature change). Thermotolerance was mainly acquired between 40-50°C during a heat slope, i.e., above the maximal temperature of growth. The death of the yeasts subjected to a heat shock might be related to the loss of membrane integrity: intracellular contents extrusion, i.e., membrane permeabilization, was found to precede cell death. However, the permeabilization did not precede cell death during a heat slope and, therefore, membrane permeabilization was a consequence rather than a cause of cell death. During a slow temperature increase, yeasts which remain viable may have time to adapt their plasma membrane and thus maintain membrane integrity.