Project description:Yeast cells can be affected during their growth to several stress conditions. One of the most known and characterised is the osmotic stress and most of the studies about osmotic sterss response in yeast have been focused on salt or sorbitol stress. However, during yeast growth in industrially relevant processes (for instance throughout alcoholic fermentation on the must to produce alcoholic beverages) the osmotic stress is mainly due to the high sugar(in particular glucose) concentration (200-250 g/L).
Project description:Yeast cells can be affected during their growth to several stress conditions. One of the most known and characterised is the osmotic stress and most of the studies about osmotic sterss response in yeast have been focused on salt or sorbitol stress. However, during yeast growth in industrially relevant processes (for instance throughout alcoholic fermentation on the must to produce alcoholic beverages) the osmotic stress is mainly due to the high sugar(in particular glucose) concentration (200-250 g/L). In this study we want to know the transcriptional response of the Saccharomyces cerevisiae when it was grown in a medium with high glucose concentration. For this aim we have grown yeast in YP medium containing 2% of glucose in cultures overnight and after that we diluted this cultures to an OD600 of 0.1 in two differents mediums: YP containing 2% or 20% of glucose.One hour later of inoculation we collect the cells and quikly frozen in liquid nitrogen. We extracted the total mRNA of the cells and after that we did the microarrays, comparing cells were grown in YP2 media against the cells were grown in YP20 media.
Project description:To better understand how yeast adapt and respond to sequential stressors, an industrial yeast strain, URM 6670 (also known as BT0510), which is highly flocculent, tolerant to ethanol, osmotic and heat shock stresses, was subjected to three different treatments: 1. osmotic stress followed by ethanol stress, 2. oxidative stress followed by ethanol stress, 3. glucose withdrawal followed by ethanol stress. Samples were collected before the first stress (control), after the first stress and after the second stress (ethanol). RNA was extracted and analyzed by RNAseq.
Project description:Fungal group III histidine kinases are the molecular targets of some classes of fungicides. In contrast to the yeast Saccharomyces cerevisiae, the fungal pathogen Candida albicans possesses a group III histidine kinase, CaNik1p, also called Cos1p. To investigate the function of CaNIK1, the gene was expressed in S. cerevisiae. The transformants became susceptible to antifungal compounds to which the wild-type strain is resistant. The susceptibility was related to the activation of the MAP kinase Hog1p of the osmotic stress response pathway. Gene expression analysis revealed a strong overlap of the responses to osmotic stress and to fludioxonil at early time points. While the response to fludioxonil persisted, the response to osmotic stress was diminished with time. S. cerevisiae expressing Candida albicans Nik1p were treated with 10 µg/ml fludioxonil. As a comparison, another culture of S. cerevisiae expressing Candida albicans Nik1p was treated with 1 M sorbitol to induce osmotic stress response. One culture remained untreated as a control. From all cultures, samples were taken after a duration of 15, 30 and 60 min.
Project description:High glucose concentrations were desirable for ethanol fermentation of Zymomonas mobilis, but it can lead to decrease in ethanol production and productivity. Sorbitol as a compatible solute can be absorbed or synthesized to counteract the detrimental osmotic stress caused from external high glucose concentrations by Z. mobilis. Currently, molecular mechanisms of tolerance to high glucose concentrations and sorbitol promoting ethanol fermentation are still unclear for Z. mobilis. To better understand mechanisms with which high concentrations of glucose and sorbitol affect physiology and metabolism of Z. mobilis ATCC31821 (ZM4), the global transcriptional responses of ZM4 to the challenge of high glucose concentration and sorbitol were profiled using whole genome microarray analysis. Swings J, Deley J. Bacterial Rev. 1977, 41(1): 1-46. Loos H, Kramer R, Sahm H and Sprenger GA. J Bacteriol. 1994, 176(24):7688–7693.
Project description:Relative quantification of protein abundances of three yeast strains (Saccharomyces cerevisiae CEN.PK113-7D, Kluyveromyces marxianus CBS6556 and Yarrowia lipolytica W29) cultivate in chemostats under different conditions. The conditions for Saccharomyces cerevisiae CEN.PK113-7D are: - Standard condition – 30°C, pH 5.5 - High temperature - 36°C, pH 5.5 - Low pH - 30°C, pH 3.5 - Osmotic stress – 30°C, pH 5.5, 1M KCl The conditions for Kluyveromyces marxianus CBS6556 are: - Standard condition – 30°C, pH 5.5 - High temperature - 40°C, pH 5.5 - Low pH - 30°C, pH 3.5 - Osmotic stress – 30°C, pH 5.5, 0.6 M KCl The conditions for Yarrowia lipolytica W29 are: - Standard condition - 28°C, pH 5.5 - High temperature - 32°C, pH 5.5 - Low pH - 28°C, pH 3.5 This study is part of the OMICS data generation of CHASSY project (European Union’s Horizon 2020 grant agreement No 720824).
Project description:We performed knockout and wild type expression experiments in yeast grown in soribtol to identify genes invovled in controling osmotic stress response. Soribitol experiments were performed by growing to logarithmic phase in synthetic complete (SC) medium and then washing and resuspending in SC medium with 1M sorbitol for 30 minutes. Two replicates were performed per knockout strain and compared with two or four control replicates depending on the platform.
Project description:Wild type and ppt1 mutant under hypo-osmotic shock. Cultures were grown with 1M sorbitol for ~20 hours, cells were collected by centrifugation and resuspended in YPD at time zero. Samples were collected at 0, 7, 15, 30 and 60 minutes after transfer to YPD. Experimental samples were used to generate Cy5-labeled cDNA probes, whereas mRNA reference pools extracted from cultures of the respective strains grown to early log phase under normal conditions, were used to generate Cy3-labeled cDNA probes. Cy5- and Cy3-labeled probes were hybridized together to microarrays printed with PCR-amplified fragments, representing 6280 of the Saccharomyces cerevisiae ORFs. Keywords: time-course
Project description:Protein extracts of three yeast strains (Saccharomyces cerevisiae CEN.PK113-7D, Kluyveromyces marxianus CBS6556 and Yarrowia lipolytica W29) cultivated in chemostats under different conditions. Representative samples containing aliquots of all conditions for each yeast strain were spiked with UPS2 standard (Sigma) to estimate absolute values in fmol. The conditions for Saccharomyces cerevisiae CEN.PK113-7D are: - Standard condition : 30°C, pH 5.5 - High temperature: 36°C, pH 5.5 - Low pH: 30°C, pH 3.5 - Osmotic stress : 30°C, pH 5.5, 1M KCl The conditions for Kluyveromyces marxianus CBS6556 are: - Standard condition : 30°C, pH 5.5 - High temperature: 40°C, pH 5.5 - Low pH: 30°C, pH 3.5 - Osmotic stress: 30°C, pH 5.5, 0.6 M KCl The conditions for Yarrowia lipolytica W29 are: - Standard condition: 28°C, pH 5.5 - High temperature: 32°C, pH 5.5 - Low pH: 28°C, pH 3.5 This study is part of the OMICS data generation WP of CHASSY project (European Union’s Horizon 2020 grant agreement No 720824).
Project description:Arabidopsis Col-0 seeds were germinated and grown for two weeks on Arabidopsis thaliana salt media (ATS, control) or ATS media supplemented 50, 75, 100 or 125 mM NaCl that imposes both an ionic and osmotic stress; or ATS media supplemented with iso-osmolar concentrations of sorbitol (100, 150, 200 or 250 mM) that imposes only an osmotic stress. The aim of the study was to identify genes involved in plant growth and adaptation to ionic stress compared to genes involved in growth and adaptation to osmotic stress conditions. To do this we identified lists of genes that are differentially expressed in plants grown in NaCl (A) and lists of genes differentially expressed in plants grown in sorbitol (B). We then compared these lists to find ionic/salt-specific genes that are only expressed in plants grown in NaCl and not in plants grown in sorbitol; and osmotic genes that are expressed both in plants grown in NaCl and in plants grown in sorbitol. Associated publication: Cackett et al. (2022) Salt-specific gene expression reveals elevated auxin levels in Arabidopsis thaliana plants grown under saline conditions, DOI: 10.3389/fpls.2022.804716