Functional Genomics in Wine Yeast: DNA Arrays and Next Generation Sequencing
Since their very beginning, DNA array and next-generation sequencing technologies have been used with Saccharomyces cerevisiae cells. In the last 7 years, an increasing number of studies have focused on the study of wine strains and winemaking. The uncovering of the genomic features of these strains and expression profiles under the different stressful conditions that they have to deal with have contributed significantly to the knowledge of how this amazing microorganism can convert grape must into a drink that has enormously influenced mankind for 7000 years.This review presents a synopsis of DNA array and next-generation sequencing (NGS) technologies and focus mainly in their use in study…
Expression profile of genes involved in hydrogen sulphide liberation by Saccharomyces cerevisiae grown under different nitrogen concentrations
AbstractThe present work aims to elucidate molecular mechanisms underlying hydrogen sulphide production in S. cerevisiae associated to nitrogen deficiency. To assess, at a genome-wide level, how the yeast strain adapted to the progressive nitrogen depletion and to nitrogen re-feeding, gene expression profiles were evaluated during fermentation at different nitrogen concentrations, using the DNA array technology. The results showed that most MET genes displayed higher expression values at the beginning of both control and N-limiting fermentation, just before the time at which the release of sulphide was observed. MET genes were downregulated when yeast stopped growing which could associate M…
Comparative Transcriptomic Analysis Reveals Similarities and Dissimilarities in Saccharomyces cerevisiae Wine Strains Response to Nitrogen Availability
Nitrogen levels in grape-juices are of major importance in winemaking ensuring adequate yeast growth and fermentation performance. Here we used a comparative transcriptome analysis to uncover wine yeasts responses to nitrogen availability during fermentation. Gene expression was assessed in three genetically and phenotypically divergent commercial wine strains (CEG, VL1 and QA23), under low (67 mg/L) and high nitrogen (670 mg/L) regimes, at three time points during fermentation (12 h, 24 h and 96 h). Two-way ANOVA analysis of each fermentation condition led to the identification of genes whose expression was dependent on strain, fermentation stage and on the interaction of both factors. The…
Transcriptional Response of Saccharomyces cerevisiae to Different Nitrogen Concentrations during Alcoholic Fermentation▿ †
Gene expression profiles of a wine strain of Saccharomyces cerevisiae PYCC4072 were monitored during alcoholic fermentations with three different nitrogen supplies: (i) control fermentation (with enough nitrogen to complete sugar fermentation), (ii) nitrogen-limiting fermentation, and (iii) the addition of nitrogen to the nitrogen-limiting fermentation (refed fermentation). Approximately 70% of the yeast transcriptome was altered in at least one of the fermentation stages studied, revealing the continuous adjustment of yeast cells to stressful conditions. Nitrogen concentration had a decisive effect on gene expression during fermentation. The largest changes in transcription profiles were o…
Saccharomyces cerevisiae signature genes for predicting nitrogen deficiency during alcoholic fermentation
Genome-wide analysis of the wine yeast strain Saccharomyces cerevisiae PYCC4072 identified 36 genes highly expressed under conditions of low or absent nitrogen in comparison with a nitrogen-replete condition. Reverse transcription-PCR analysis for four of these transcripts with this strain and its validation with another wine yeast strain underlines the usefulness of these signature genes for predicting nitrogen deficiency and therefore the diagnosis of wine stuck/sluggish fermentations.