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PubMed · 15971585

Enhancements in ethanol tolerance of a self-flocculating yeast by calcium ion through decrease in plasmalemma permeability.

Chun-Keng Hu·Feng-Wu Bai·Li-Jia An
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Abstract

Ca2+ at 1.64 mmol/L markedly increased ethanol tolerance of a self-flocculating fusant of Schizosaccharomyces pombe and Saccharomyces cerevisiae. After 9 h of exposure to 20% (V/V) ethanol at 30 degrees C , no viability remained for the control whereas 50.0% remained for the cells both grown and incubated with ethanol in Ca2+ -added medium. Furthermore, when subjected to 15% (V/V) ethanol at 30 degrees C, the equilibrium nucleotide concentration and plasma membrane permeability coefficient (P' ) of the cells both grown and incubated with ethanol in Ca2+ -added medium accounted for only 50.0% and 29.3% those of the control respectively, indicating that adding Ca2+ can markedly reduce plasma membrane permeability of yeast cells under ethanol stress as compared with the control. Meanwhile, high viability levels acquired by the addition of Ca2+ exactly corresponded to the striking decreases in extracellular nucleotide concentration and P' achieved with identical approach. Therefore, the enhancing effect of Ca2+ on ethanol tolerance of this strain is closely related to its ability to decrease plasma membrane permeability of yeast cells subjected to ethanol stress.

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CalciumCell MembraneCell Membrane PermeabilityEthanolSaccharomyces cerevisiaeSchizosaccharomycesTemperatureJournal ArticleResearch Support, Non-U.S. Gov't

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Chun-Keng Hu, Feng-Wu Bai, Li-Jia An. 2003. Enhancements in ethanol tolerance of a self-flocculating yeast by calcium ion through decrease in plasmalemma permeability.. https://pubmed.ncbi.nlm.nih.gov/15971585/

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