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Saccharomyces cerevisiae does not undergo a quorum sensing-dependent switch of budding pattern
Michela Winters1, Violetta Aru2, Kate Howell3
1School of Agriculture and Food, Faculty of Veterinary and Agricultural Science, University of Melbourne, Parkville, 3010, Australia.
Scientific Reports
|May 24, 2022
Summary
Quorum sensing may not control Saccharomyces cerevisiae budding. Researchers found cell density, nitrogen levels, and metabolites alone don't trigger unipolar budding, suggesting other factors are involved.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- Saccharomyces cerevisiae exhibits morphological changes, including filamentous growth and unipolar budding, in response to environmental stressors.
- Filamentous growth induction is hypothesized to occur under nitrogen deficiency, mediated by alcoholic signaling molecules via quorum sensing.
Purpose of the Study:
- To investigate the role of quorum sensing in controlling the budding pattern switch in Saccharomyces cerevisiae under varying environmental conditions.
- To analyze the relationship between cell density, metabolite concentration, nitrogen availability, and the induction of unipolar budding.
Main Methods:
- Monitored the budding pattern of S. cerevisiae cells over time.
- Measured cell density and extracellular metabolite concentrations concurrently.
- Assessed budding patterns under low and high nitrogen conditions, in conditioned media, and with varying concentrations of 2-phenylethanol.
Main Results:
- Unipolar budding increased with cell density under both low and high nitrogen conditions, but these factors alone were insufficient to induce the switch.
- Conditioned media and critical cell densities did not consistently reproduce the increase in unipolar budding.
- A high, non-physiologically relevant concentration of 2-phenylethanol increased unipolar budding, suggesting toxicity rather than quorum sensing.
Conclusions:
- Cell density, metabolite concentration, and nitrogen deficiency are not sufficient to increase unipolar budding in S. cerevisiae.
- The study suggests that quorum sensing, as currently understood, may not directly control the switch to unipolar budding behavior.
- The observed effects of 2-phenylethanol at high concentrations indicate potential toxicity rather than a signaling mechanism.
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