Different mechanisms of resistance modulate sulfite tolerance in wine yeasts

Abstract

From a technological point of view, yeast resistance to sulfite is of great interest and represents an important technological character for winemaking. Several mechanisms are involved, and strain-dependent strategies to obtain SO2 resistance can deeply influence wine quality, although this choice is less relevant in determining the technological performance of the strain during fermentation. In this study, to better understand the strain-specific mechanisms of resistance, 11 Saccharomyces cerevisiae strains, whose genomes have been previously sequenced, were selected. Their attitude towards sulfites, in terms of resistance and production, was evaluated, and RNA-sequencing of four selected strains was performed during fermentation process in synthetic grape must in the presence of SO2. Results demonstrated that at molecular level, the physical effect of SO2 triggered multiple stress responses in the cell and high tolerance to general enological stressing condition increased SO2 resistance. Adaptation mechanism due to high basal gene expression level rather than specific gene induction in the presence of sulfite seemed to be responsible in modulating strain resistance. This mechanism involved higher basal gene expression level of specific cell wall proteins, enzymes for lipid biosynthesis, and enzymes directly involved in SO2 assimilation pathway and efflux.

Characterization and emulsifying properties of extracts obtained by physical and enzymatic methods from an oenological yeast strain

“…The solution was incubated under vacuum for 2 h at 110 ∘ C. After the tube was cooled to room temperature, 800 μL of hydrolysate were mixed with 800 μL of water. Glucose and mannose were determined by high-performance liquid chromatography (HPLC) as described by Nadai et al 15 follows: 10 μL of hydrolysed polysaccharides solution were injected into a Waters 1525 HPLC binary pump (Waters Corporation, Milford, MA, USA) equipped with a 300 × 7.8 mm stainless steel column packed with Aminex HPX_87H (Bio-Rad Laboratories, Hercules, CA, USA) and a Waters 2414 Refractive Index Detector (Waters Corporation). The elution was performed in isocratic mode with 5 mmol L −1 sulphuric acid at a flow rate of 0.6 mL min −1 .…”

A new chromosomal rearrangement improves the adaptation of wine yeasts to sulfite

“…The latter is one of the most effective mechanisms of sulfite resistance in S. cerevisiae (Avram and Bakalinsky, 1997;Avram et al, 1999). Strains lacking SSU1 gene are more sensitive to sulfite than their wild-type counterparts, because SSU1 deletion increases the accumulation of intracellular sulfite (Avram and Bakalinsky, 1997;Nadai et al, 2016). Another gene involved in yeast sulfite resistance is the transcription factor FZF1 (Casalone et al, 1992(Casalone et al, , 1994Avram et al, 1999;Engle and Fay, 2012).…”

Adaptation of Candida albicans to Reactive Sulfur Species

“…Resistance of S. cerevisiae to either sulfite or RNS is mediated by transcriptional responses that require the Five Zinc Finger transcription factor FZF1 (Casalone et al 1994;Avram et al 1999;Park and Bakalinsky 2000;Sarver and DeRisi 2005;Engle and Fay 2012). Although the mechanism of sulfite resistance in S. cerevisiae has been investigated, responses to sulfite by other physiological relevant yeasts, such as the opportunistic fungal pathogen C. albicans, are less clearly understood (Nadai et al 2016).…”