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Anhydrobiosis in yeast: stabilization by exogenous lactose
A I Rapoport1, G M Khroustalyova, L M Crowe
1Laboratory of Cell Biology, Institute of Microbiology and Biotechnology, Latvian University, Kronvald blvd. 4, LV- 1586 Riga, Latvia. rapoport@mail.eunet.lv
Mikrobiologiia
|November 11, 2009
Summary
Adding lactose to Saccharomyces cerevisiae yeast cultures enhances cell stability during dehydration and rehydration. This sugar solution protects yeast cells by reducing plasma membrane damage and leakage, improving overall viability.
Area of Science:
- * Biochemistry and Molecular Biology
- * Yeast Physiology and Stress Response
Background:
- * Yeast cultures, particularly Saccharomyces cerevisiae, are susceptible to cellular damage and death when subjected to dehydration and rehydration cycles.
- * Plasma membrane integrity and function are critical for yeast survival under stress conditions.
Purpose of the Study:
- * To investigate the protective effect of lactose solutions on Saccharomyces cerevisiae cells against dehydration-induced damage.
- * To elucidate the mechanisms by which lactose enhances yeast cell stability during rehydration.
Main Methods:
- * Incubation of Saccharomyces cerevisiae cultures in 0.75 M lactose solutions.
- * Assessment of cell viability and plasma membrane permeability after dehydration and rehydration.
- * Fourier transform infrared spectroscopy (FTIR) to analyze lipid phase transition temperatures in cell membranes.
Main Results:
- * Lactose treatment significantly increased the stability and viability of yeast cells during dehydration.
- * A notable decrease in plasma membrane permeability was observed during rehydration of lactose-treated cells.
- * Fourier transform infrared spectroscopy revealed that lactose depressed the membrane phospholipid phase transition temperature.
Conclusions:
- * Lactose acts as a cryoprotectant, enhancing the stability of Saccharomyces cerevisiae during dehydration by altering membrane properties.
- * The protective effect is attributed to the depression of the lipid phase transition temperature, which mitigates molecular damage to membranes during rehydration.
- * Lactose treatment effectively reduces cellular leakage and improves the survival rate of dry yeast cells.
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