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Mitochondrial Respiration Quantification in Yeast Whole Cells
Published on: November 8, 2024
Variation in yeast mitochondrial activity associated with asci
Chantel W Swart1, Pieter W J van Wyk, Carolina H Pohl
1UNESCO-MIRCEN: Industrial Biotechnology, Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, P.O. Box 339, Bloemfontein, 9300, South Africa.
Canadian Journal of Microbiology
|July 22, 2008
Summary
Yeast ascus formation does not always require increased mitochondrial activity. Fermentation can provide sufficient energy, as seen in Zygosaccharomyces bailii, enabling ascus development without a rise in mitochondrial membrane potential or oxylipin production.
Area of Science:
- Cellular Biology
- Microbiology
- Yeast Physiology
Background:
- Ascus formation in yeasts is a critical reproductive process.
- Mitochondrial activity, including membrane potential (DeltaPsim) and oxylipin production, is often associated with cellular energy demands.
- The role of mitochondrial energetics in yeast ascus development has been a subject of investigation.
Purpose of the Study:
- To investigate the correlation between mitochondrial activity and ascus formation in various yeast species.
- To determine if increased mitochondrial membrane potential and oxylipin production are essential for ascus development.
- To explore alternative energy sources, such as fermentation, for ascus formation.
Main Methods:
- Measurement of mitochondrial membrane potential (DeltaPsim) in yeast asci.
- Quantification of mitochondrially produced 3-hydroxy (3-OH) oxylipins.
- Assessment of ascus formation under conditions of oxygen deprivation.
- Comparison of mitochondrial activity and ascus development across different yeast species (Galactomyces reessii, Lipomyces starkeyi, Pichia farinosa, Schizosaccharomyces octosporus, and Zygosaccharomyces bailii).
Main Results:
- Increased mitochondrial activity (DeltaPsim and 3-OH oxylipins) was observed in asci of nonfermentative yeasts (G. reessii, L. starkeyi) and some fermentative yeasts (P. farinosa, S. octosporus).
- Notably, Zygosaccharomyces bailii asci exhibited no increase in mitochondrial activity during ascus formation.
- Oxygen deprivation inhibited ascus formation only in yeast species that showed increased mitochondrial activity, while Z. bailii's ascus formation was unaffected.
Conclusions:
- Ascus formation in yeasts is not universally dependent on elevated mitochondrial activity.
- Fermentation can serve as an adequate energy source for ascus development in certain yeast species, exemplified by Zygosaccharomyces bailii.
- These findings highlight the metabolic flexibility of yeasts in reproduction.
