1,517 research outputs found
Functional analysis of stress protein data in a flor yeast subjected to a biofilm forming condition
AbstractIn this data article, an OFFGEL fractionator coupled to LTQ Orbitrap XL MS equipment and a SGD filtering were used to detect in a biofilm-forming flor yeast strain, the maximum possible number of stress proteins under the first stage of a biofilm formation conditions (BFC) and under an initial stage of fermentation used as reference, so-called non-biofilm formation condition (NBFC). Protein functional analysis – based on cellular components and biological process GO terms – was performed for these proteins through the SGD Gene Ontology Slim Mapper tool. A detailed analysis and interpretation of the data can be found in “Stress responsive proteins of a flor yeast strain during the early stages of biofilm formation” [1]
Shedding light on the chromatin changes that modulate shade responses
Altres ajuts: COST-Action INDEPTH CA16212; Generalitat de Catalunya/CERCA programmePerception of vegetation proximity or plant shade informs of potential competition for resources by the neighboring vegetation. As vegetation proximity impacts on both light quantity and quality, perception of this cue by plant photoreceptors reprograms development to result in responses that allow plants to compete with the neighboring vegetation. Developmental reprogramming involves massive and rapid changes in gene expression, with the concerted action of photoreceptors and downstream transcription factors. Changes in gene expression can be modulated by epigenetic processes that alter chromatin compaction, influencing the accessibility and binding of transcription factors to regulatory elements in the DNA. However, little is known about the epigenetic regulation of plant responses to the proximity of other plants. In this manuscript, we review what is known about plant shade effects on chromatin changes at the cytological level, that is, changes in nuclear morphology and high order chromatin density. We address which are the specific histone post-transcriptional modifications that have been associated with changes in shade-regulated gene expression, such as histone acetylation and histone methylation. Furthermore, we explore the possible mechanisms that integrate shade signaling components and chromatin remodelers to settle epigenetic marks at specific loci. This review aims to be a starting point to understand how a specific environmental cue, plant shade, integrates with chromatin dynamics to implement the proper acclimation responses
Grape musts differentiation based on selected aroma compounds using SBSE-GC-MS and statistical analysis
Fifty-one aroma compounds in musts from 'Muscat
Ottonel', 'Aligoté', 'Muscat of Alexandria' and 'Pedro
Ximénez' white grapes have been determined, three
of them identified for the first time in grapes. Two fingerprints
for each cultivar, based in 6 groups of aroma
compounds before and after acidic hydrolysis of the
musts were obtained by Multiple Variable Analysis.
Only 17 aroma compounds before and 21 after hydrolysis,
were selected by their high discriminating power.
The Principal Component Analysis carried out with
data of these selected compounds provided two components
explaining 85.11 % of the overall variance for
free aroma compounds and 87.58 % for those obtained
after hydrolysis of musts, allowing an objective differentiation
of each cultivar
Análisis espacial medioambiental de la mortalidad en el municipio de Madrid.
The first purpose of this study is to compare mortality indicators in the 21 districts of Madrid for 1987-88 and 1995-96 periods. Mortality indicator used Aceptado: 15/V/2001. * Departamento de Ecología Humana y Población. Universidad Complutense de Madrid. 353 Jaime Martín Moreno, et al. Análisis espacial medioambiental de la mortalidad... were the comparative mortality figure with the direct method. The second purpose is to identify differences in mortality between districts in function of certain socioeconomic factors. Socioeconomic indicators were the rate of unemployed, rate of people without studies, rate of people with high studies, rate of unskilled workers and the rate of managerial workers. The statistical correlation between socioeconomic indicators and mortality indicators was studied by Spearman's rank correlation coefficient. This study has detected significant differences in mortality between the 21 districts of Madrid and high correlation between mortality and socioeconomic indicators.El primer objetivo del estudio es comparar la mortalidad en los 21 distritos de Madrid para los periodos 1987-88 y 1995-96. El indicador de mortalidad utilizado fue la tasa comparativa de mortalidad mediante el método directo. El segundo objetivo es identificar diferencias en mortalidad entre distritos en función de ciertos factores socioeconómicos. Los factores socioeconómicos que se han tenido en cuenta son la tasa de desempleo, la tasa de personas sin estudios, tasa de personas con estudios universitarios, tasa de trabajadores no cualificados y tasa de trabajadores dentro de la categoría de directivos. Se ha utilizado el coeficiente de correlación de Spearman. En el estudio se han detectado importantes diferencias de mortalidad entre los 21 distritos de Madrid, observándose una fuerte correlación entre la mortalidad y los indicadores socioeconómicos utilizados
First Proteomic Approach to Identify Cell Death Biomarkers in Wine Yeasts during Sparkling Wine Production
Apoptosis and later autolysis are biological processes which take place in Saccharomyces cerevisiae during industrial fermentation processes, which involve costly and time-consuming aging periods. Therefore, the identification of potential cell death biomarkers can contribute to the creation of a long-term strategy in order to improve and accelerate the winemaking process. Here, we performed a proteomic analysis based on the detection of possible apoptosis and autolysis protein biomarkers in two industrial yeast strains commonly used in post-fermentative processes (sparkling wine secondary fermentation and biological aging) under typical sparkling wine elaboration conditions. Pressure had a negatively effect on viability for flor yeast, whereas the sparkling wine strain seems to be more adapted to these conditions. Flor yeast strain experienced an increase in content of apoptosis-related proteins, glucanases and vacuolar proteases at the first month of aging. Significant correlations between viability and apoptosis proteins were established in both yeast strains. Multivariate analysis based on the proteome of each process allowed to distinguish among samples and strains. The proteomic profile obtained in this study could provide useful information on the selection of wine strains and yeast behavior during sparkling wine elaboration. Additionally, the use of flor yeasts for sparkling wine improvement and elaboration is proposed
A Differential Proteomic Approach to Characterize the Cell Wall Adaptive Response to CO2 Overpressure during Sparkling Wine-Making Process
In this study, a first proteomic approach was carried out to characterize the adaptive response of cell wall-related proteins to endogenous CO2 overpressure, which is typical of second fermentation conditions, in two wine Saccharomyces cerevisiae strains (P29, a conventional second fermentation strain, and G1, a flor yeast strain implicated in sherry wine making). The results showed a high number of cell wall proteins in flor yeast G1 under pressure, highlighting content at the first month of aging. The cell wall proteomic response to pressure in flor yeast G1 was characterized by an increase in both the number and content of cell wall proteins involved in glucan remodeling and mannoproteins. On the other hand, cell wall proteins responsible for glucan assembly, cell adhesion, and lipid metabolism stood out in P29. Over-represented proteins under pressure were involved in cell wall integrity (Ecm33p and Pst1p), protein folding (Ssa1p and Ssa2p), and glucan remodeling (Exg2p and Scw4p). Flocculation-related proteins were not identified under pressure conditions. The use of flor yeasts for sparkling wine elaboration and improvement is proposed. Further research based on the genetic engineering of wine yeast using those genes from protein biomarkers under pressure alongside the second fermentation in bottle is required to achieve improvements
Effect of Bentonite Addition to Pedro Ximénez White Grape Musts before Their Fermentation with Selected Yeasts on the Major Volatile Compounds and Polyols of Wines and Tentative Relationships with the Sensorial Evaluation
In this work, we study the effect of bentonite addition to the grape must before alcoholic fermentation on the chemical composition and sensorial profile of the obtained wines. Fermentations were carried out with two Saccharomyces cerevisiae commercial active dry yeasts treated or not with bentonite and were compared with a control wine obtained by spontaneous fermentation (using the grape must microbiota). Several significant effects on the chemical and sensorial attributes were established by statistical treatments. The selection by multiple variable analysis of seven volatile molecules (ethyl acetate; methanol; 1-propanol; isobutanol; 2-methyl-1-butanol; 3-metyl-1-butanol and 2-phenylethanol) provided several footprints that provide an easy visualization of bentonite effects on wine volatile compounds. A Principal Component Analysis carried out with all the compounds quantified by Gas-Chromatography revealed that the first two Principal Components explain 60.15 and 25.91%, respectively, of the total variance and established five groups that match with the five wines analyzed. Lastly, predictive models at p ≤ 0.05 level for the attributes sight, smell and taste were obtained by Partial Least Squared regression analysis of selected chemical variables
Metabolic Changes by Wine Flor-Yeasts with Gluconic Acid as the Sole Carbon Source
Gluconic acid consumption under controlled conditions by a Saccharomyces cerevisiae flor yeast was studied in artificial media. Gluconic acid was the sole carbon source and the compounds derived from this metabolism were tracked by endo-metabolomic analysis using a Gas Chromatography-Mass Spectrometry (GC-MSD) coupled methodology. After 6 days, about 30% of gluconic acid (1.5 g/L) had been consumed and 34 endo-metabolites were identified. Metabolomic pathway analysis showed the TCA cycle, glyoxylate-dicarboxylate, glycine-serine-threonine, and glycerolipid metabolic pathway were significantly affected. These results contribute to the knowledge of intracellular metabolomic fluctuations in flor yeasts during gluconic acid uptake, opening possibilities for future experiments to improve their applications to control gluconic acid contents during the production of fermented beverages
Endogenous CO2 Overpressure Effect on Higher Alcohols Metabolism during Sparkling Wine Production
Higher alcohols produced by yeast during the fermentation of sparkling wine must have the greatest impact on the smell and taste of wine. At present, the metabolic response to methanol and higher alcohols formation of Saccharomyces cerevisiae under endogenous CO2 overpressure has not been fully elucidated. In this work, a proteomics and metabolomics approach using a OFFGEL fractionator and the LTQ Orbitrap for the protein identification, followed by a metabolomic study for the detection and quantification of both higher alcohols (GC-FID and SBSE-TD-GC-MS) and amino acids (HPLC), was carried out to investigate the proteomic and metabolomic changes of S. cerevisiae in relation to higher alcohols formation under a CO2 overpressure condition in a closed bottle. The control condition was without CO2 overpressure in an open bottle. Methanol and six higher alcohols were detected in both conditions, and we have been able to relate to a total of 22 proteins: 15 proteins in the CO2 overpressure condition and 22 proteins in the control condition. As for the precursors of higher alcohols, 18 amino acids were identified in both conditions. The metabolic and proteomic profiles obtained in both conditions were different, so CO2 overpressure could be affecting the metabolism of higher alcohols. Furthermore, it was not possible to establish direct correlations in the condition under CO2 overpressure; however, in the condition without pressure it was possible to establish relationships. The data presented here can be considered as a platform that serves as a basis for the S. cerevisiae metabolome–proteome with the aim of understanding the behavior of yeast under conditions of second fermentation in the production of sparkling wines.info:eu-repo/semantics/publishedVersio
Differential Response of the Proteins Involved in Amino Acid Metabolism in Two Saccharomyces cerevisiae Strains during the Second Fermentation in a Sealed Bottle
The traditional method for sparkling wine making consists of a second fermentation of a base wine followed by ageing in the same bottle that reaches the consumers. Nitrogen metabolism is the second most important process after carbon and takes place during wine fermentation by yeast. Amino acids are the most numerous nitrogen compounds released by this process. They contribute to the organoleptic properties of the wines and, therefore, to their sensory quality. The main objective of this study is to compare the differential proteomic response of amino acid metabolism, specifically their proteins and their interactions in the G1 strain (unconventional yeast) during sparkling wine production versus the conventional P29 strain. One of the new trends in winemaking is the improvement of the organoleptic diversity of wine. We propose the use of unconventional yeast that shows desirable characteristics for the industry. For this purpose, these two yeasts were grown at sealed bottle conditions for the second fermentation (Champenoise method). No differences were obtained in the middle of fermentation between the yeast strains. The number of proteins identified, and the relationships established, were similar, highlighting lysine metabolism. At the end of the second fermentation, the difference between each strain was remarkable. Hardly any proteins were identified in unconventional versus conventional yeast. However, in both strains, the metabolism of sulfur amino acids, methionine, and cysteine obtained a greater number of proteins involved in these processes. The release of these amino acids to the medium would allow the yeast to balance the internal redox potential by reoxidation of NADPH. This study is focused on the search for a more complete knowledge of yeast metabolism, specifically the metabolism of amino acids, which are key compounds during the second fermentation
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