RESUMO
We have found that incubation in lactose solutions (0.75 M) of yeast culture Saccharomyces cerevisiae sensitive to dehydration damage increased the stability of the cells during dehydration. Simultaneously with this increase in viability, a decrease in plasma membrane permeability during rehydration was seen. Using Fourier transform infrared spectroscopy to measure lipid phase transitions, we observed that the lactose treatment depressed the membrane phospholipid phase transition temperature in a sensitive culture of dry yeast. As a result, it leads to the decrease in the damages of molecular organization of membranes during rehydration of dry yeast cells, thus reducing leakage from the cells.
Assuntos
Adaptação Fisiológica , Lactose/fisiologia , Saccharomyces cerevisiae/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Lactose/metabolismo , Lactose/farmacologia , Fosfolipídeos/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismoRESUMO
Intracellular substances released into the medium during rehydration of dry yeast cells can significantly improve the quality of a synthetic medium. Acceleration of yeast growth in this medium and increased yield of biomass are observed simultaneously. The change in the molecular arrangement of intracellular membranes as a result of the strong dehydration of live organisms is a negative phenomenon that reduces the level of cell viability. However, this phenomenon also represents an adaptive mechanisms which facilitates the maintenance of population viability as a whole under extreme environmental conditions.