Project description:Comparative gene expression analysis of two wine yeast strains at three time points (days 2, 5 and 14) during fermentation of colombar must. In our study we conducted parallel fermentations with the VIN13 and BM45 wine yeast strains in two different media, namely MS300 (syntheticmust) and Colombar must. The intersection of transcriptome datasets from both MS300 (simulated wine must;GSE11651) and Colombar fermentations should help to delineate relevant and ‘noisy’ changes in gene expression in response to experimental factors such as fermentation stage and strain identity.
Project description:Comparison between two commercial wine yeast strains (UCD522 and P29) differing in their production of H2S during wine fermentation.
Project description:Industrial wine yeast strains possess specific abilities to ferment under stressing conditions and give a suitable aromatic outcome. Although the fermentations properties of Saccharomyces cervisiae wine yeasts are well documented little is known on the genetic basis underlying the fermentation traits. Besides, although strain differences in gene expression has been reported, their relationships with gene expression variations and fermentation phenotypic variations is unknown. To both identify the genetic basis of fermentation traits and get insight on their relationships with gene expression variations, we combined fermentation traits QTL mapping and expression profiling in a segregating population from a cross between a wine yeast derivative and a laboratory strain.
Project description:Comparative gene expression analysis of two wine yeast strains at three time points (days 2, 5 and 14) during fermentation of colombar must. In our study we conducted parallel fermentations with the VIN13 and BM45 wine yeast strains in two different media, namely MS300 (syntheticmust) and Colombar must. The intersection of transcriptome datasets from both MS300 (simulated wine must;GSE11651) and Colombar fermentations should help to delineate relevant and ânoisyâ changes in gene expression in response to experimental factors such as fermentation stage and strain identity. Experiment Overall Design: Two industrial wine yeast strains (BM45 and VIN13) grown micro-aerobically in Colombar must. Microarray analysis was performed at three time points during fermentation (days 2, 5 and 14), representing the exponential, early and late stationary growth phases respectively.
Project description:Comparison between two commercial wine yeast strains (UCD522 and P29) differing in their production of H2S during wine fermentation. Due to the characteristics of the strains (commercial, non-standard wine strains), the experiment was duplicated using two completely different platforms and techniques (cDNA-based and in situ synthesized oligonucleotide-based). UCD522 and P29 wine microfermentations were performed in parallel and yeast samples were taken at the stage of fastest fermentation rate. Two biological replicates per yeast strain.
Project description:We performed here the transcriptomic profile of 44 segregants from a cross between S288c and 59A (a spore of EC1118 strain). The analysis was performed in wine fermentation condition in stationary phase during nitrogen starvation and in alcoholic stress. These data, associated with an individual genotyping by Affymetrix array allow us to highlight genetic variations involved in perturbation of regulatory network and fermentative behavior.
Project description:In wine fermentation, the blending of non-Saccharomyces yeast with Saccharomyces cerevisiae to improve the complexity of wine has become common practice, but data regarding the impact on yeast physiology and on genetic and metabolic regulation remain limited. Here we describe a transcriptomic analysis of single species and mixed species fermentations.
Project description:We used genome-wide expression analyses to study the response of Saccharomyces cerevisiae to stress throughout a 15-day wine fermentation. Forty percent of the yeast genome significantly changed expression levels to mediate long-term adaptation to an environment in which ethanol is both a stressor and a carbon source. Within this set, we identify a group of 223 genes, designated as the Fermentation Stress Response (FSR), that are dramatically and permanently induced; FSR genes exhibited changes ranging from four-to eighty-fold. The FSR is novel; 62% of the genes involved have not been implicated in global stress responses and 28% of the genes have no functional annotation. Genes involved in respiratory metabolism and gluconeogenesis were expressed during fermentation despite the presence of high concentrations of glucose. Ethanol, rather than nutrient depletion, was responsible for entry of yeast cells into stationary phase. Ethanol seems to regulate yeast metabolism through hitherto undiscovered regulatory networks during wine fermentation. Keywords: time course, stress response, fermentation
Project description:Industrial wine yeast strains possess specific abilities to ferment under stressing conditions and give a suitable aromatic outcome. Although the fermentations properties of Saccharomyces cervisiae wine yeasts are well documented little is known on the genetic basis underlying the fermentation traits. Besides, although strain differences in gene expression has been reported, their relationships with gene expression variations and fermentation phenotypic variations is unknown. To both identify the genetic basis of fermentation traits and get insight on their relationships with gene expression variations, we combined fermentation traits QTL mapping and expression profiling in a segregating population from a cross between a wine yeast derivative and a laboratory strain. 40 samples are analysed with 2 technical replicates, using a unique reference named pool of the 30 segregants. The transcriptome of each segregant is compared to the transcriptome of the pool. The transcriptome of 5 biologic replicates of each parental strain is also compared to this reference. An haploid derivative of the commercialized wine yeast EC1118 which sequence is available (Novo et al. 2009. PNAS, 106:16333-16338) called 59A was used as industrial wine yeast. It is a prototroph strain and has a MATa sexual type. The haploid laboratory strain S288C (MATa) was used for crossing.