title: Intracellular glycerol influences resistance to freeze stress in Saccharomyces cerevisiae: analysis of a quadruple mutant in glycerol dehydrogenase genes and glycerol-enriched cells.
abstract: Glycerol is well known as a cryoprotectant similar to trehalose. However, there is little information about the effects of intracellular glycerol on the freeze-thaw stress tolerance of yeast. Through analysis of a quadruple-knockout mutant of glycerol dehydrogenase genes (ara1 Delta gcy1 Delta gre3 Delta ypr1 Delta) in Saccharomyces cerevisiae, we revealed that the decrease in glycerol dehydrogenase activity led to increased levels of intracellular glycerol. We also found that this mutant showed higher tolerance to freeze stress than wild type strain W303-1A. Furthermore, we demonstrated that intracellular-glycerol-enriched cells cultured in glycerol medium acquire tolerance to freeze stress and retain high leavening ability in dough even after frozen storage for 7 days. These results suggest the possibility of using intracellular-glycerol-enriched cells to develop better frozen dough.
authors.affiliation: Laboratory of Molecular Microbiology, Graduate School of Agriculture, Kyoto University, Kyoto 611-0011, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Izawa
authors.forename: Machiko
authors.initials: M
authors.lastname: Sato
authors.forename: Kumio
authors.initials: K
authors.lastname: Yokoigawa
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Inoue
mesh_terms: D005285:Fermentation / Q000235:genetics; D005524:Food Technology; D005615:Freezing; D005990:Glycerol / Q000378:metabolism*; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics* / Q000378:metabolism; D013401:Sugar Alcohol Dehydrogenases / Q000235:genetics* / Q000378:metabolism; D013997:Time Factors
chemical_list: D013401:Sugar Alcohol Dehydrogenases; C020672:glycerol dehydrogenase; D005990:Glycerol