title: Physiological and transcriptional responses of anaerobic chemostat cultures of Saccharomyces cerevisiae subjected to diurnal temperature cycles.
abstract: Diurnal temperature cycling is an intrinsic characteristic of many exposed microbial ecosystems. However, its influence on yeast physiology and the yeast transcriptome has not been studied in detail. In this study, 24-h sinusoidal temperature cycles, oscillating between 12°C and 30°C, were imposed on anaerobic, glucose-limited chemostat cultures of Saccharomyces cerevisiae. After three diurnal temperature cycles (DTC), concentrations of glucose and extracellular metabolites as well as CO2 production rates showed regular, reproducible circadian rhythms. DTC also led to waves of transcriptional activation and repression, which involved one-sixth of the yeast genome. A substantial fraction of these DTC-responsive genes appeared to respond primarily to changes in the glucose concentration. Elimination of known glucose-responsive genes revealed an overrepresentation of previously identified temperature-responsive genes as well as genes involved in the cell cycle and de novo purine biosynthesis. In-depth analysis demonstrated that DTC led to a partial synchronization of the cell cycle of the yeast populations in chemostat cultures, which was lost upon release from DTC. Comparison of DTC results with data from steady-state cultures showed that the 24-h DTC was sufficiently slow to allow S. cerevisiae chemostat cultures to acclimate their transcriptome and physiology at the DTC temperature maximum and to approach acclimation at the DTC temperature minimum. Furthermore, this comparison and literature data on growth rate-dependent cell cycle phase distribution indicated that cell cycle synchronization was most likely an effect of imposed fluctuations of the relative growth rate (μ/μmax) rather than a direct effect of temperature.
authors.affiliation: Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Delft, The Netherlands Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands.
authors.forename: Marit
authors.initials: M
authors.lastname: Hebly
authors.affiliation: Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands Delft Bioinformatics Lab, Department of Intelligent Systems, Delft University of Technology, Delft, The Netherlands.
authors.forename: Dick
authors.initials: D
authors.lastname: de Ridder
authors.affiliation: Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Delft, The Netherlands Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands.
authors.forename: Erik A F
authors.initials: EA
authors.lastname: de Hulster
authors.affiliation: Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Delft, The Netherlands Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands.
authors.forename: Pilar
authors.initials: P
authors.lastname: de la Torre Cortes
authors.affiliation: Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Delft, The Netherlands Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands.
authors.forename: Jack T
authors.initials: JT
authors.lastname: Pronk
authors.affiliation: Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Delft, The Netherlands Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands P.A.S.Daran-Lapujade@tudelft.nl.
authors.forename: Pascale
authors.initials: P
authors.lastname: Daran-Lapujade
mesh_terms: D000222:Adaptation, Physiological; D000693:Anaerobiosis; D003470:Culture Media / Q000737:chemistry; D017753:Ecosystem; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D005947:Glucose / Q000737:chemistry; D025341:Principal Component Analysis; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000502:physiology*; D013696:Temperature; D059467:Transcriptome
chemical_list: D003470:Culture Media; D005947:Glucose