title: CDC19 encoding pyruvate kinase is important for high-temperature tolerance in Saccharomyces cerevisiae.
abstract: Use of thermotolerant strains is a promising way to reduce the cost of maintaining optimum temperatures in the fermentation process. Here we investigated genetically a Saccharomyces cerevisiae strain showing a high-temperature (41°C) growth (Htg(+)) phenotype and the result suggested that the Htg(+) phenotype of this Htg(+) strain is dominant and under the control of most probably six genes, designated HTG1 to HTG6. As compared with a Htg(-) strain, the Htg(+) strain showed a higher survival rate after exposure to heat shock at 48°C. Moreover, the Htg(+) strain exhibited a significantly high content of trehalose when cultured at high temperature and stronger resistance to Congo Red, an agent that interferes with cell wall construction. These results suggest that a strengthened cell wall in combination with increased trehalose accumulation can support growth at high temperature. The gene CDC19, encoding pyruvate kinase, was cloned as the HTG2 gene. The CDC19 allele from the Htg(+) strain possessed five base changes in its upstream region, and two base changes resulting in silent mutations in its coding region. Interestingly, the latter base changes are probably responsible for the increased pyruvate kinase activity of the Htg(+) strain. The possible mechanism leading to this increased activity and to the Htg(+) phenotype, which may lead to the activation of energy metabolism to maintain cellular homeostasis, is discussed.
authors: Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita-shi, Osaka 565-0871, Japan.
authors: Suthee
authors: S
authors: Benjaphokee
authors: Preeyaporn
authors: P
authors: Koedrith
authors: Choowong
authors: C
authors: Auesukaree
authors: Thipa
authors: T
authors: Asvarak
authors: Minetaka
authors: M
authors: Sugiyama
authors: Yoshinobu
authors: Y
authors: Kaneko
authors: Chuenchit
authors: C
authors: Boonchird
authors: Satoshi
authors: S
authors: Harashima
mesh_terms: D018797:Cell Cycle Proteins / Q000378:metabolism*; D018869:Heat-Shock Response / Q000502:physiology*; D006358:Hot Temperature; D011770:Pyruvate Kinase / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000145:classification* / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D018797:Cell Cycle Proteins; D029702:Schizosaccharomyces pombe Proteins; D011770:Pyruvate Kinase; C085710:mcm2 protein, S pombe