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Juan C. Mauricio - One of the best experts on this subject based on the ideXlab platform.

  • Comparative Study of the Proteins Involved in the Fermentation-Derived Compounds in Two Strains of Saccharomyces cerevisiae during Sparkling Wine Second Fermentation
    Microorganisms, 2020
    Co-Authors: María Del Carmen González-jiménez, Juan C. Mauricio, Teresa García-martínez, Irene Sánchez-león, Anna Puig-pujol, Juan Antonio Moreno, Jaime Moreno-garcía
    Abstract:

    Sparkling wine is a distinctive wine. Saccharomyces cerevisiae Flor Yeasts is innovative and ideal for the sparkling wine industry due to the Yeasts’ resistance to high ethanol concentrations, surface adhesion properties that ease wine clarification, and the ability to provide a characteristic volatilome and odorant profile. The objective of this work is to study the proteins in a Flor yeast and a conventional yeast that are responsible for the production of the volatile compounds released during sparkling wine elaboration. The proteins were identified using the OFFGEL fractionator and LTQ Orbitrap. We identified 50 and 43 proteins in the Flor yeast and the conventional yeast, respectively. Proteomic profiles did not show remarkable differences between strains except for Adh1p, Fba1p, Tdh1p, Tdh2p, Tdh3p, and Pgk1p, which showed higher concentrations in the Flor yeast versus the conventional yeast. The higher concentration of these proteins could explain the fuller body in less alcoholic wines obtained when using Flor Yeasts. The data presented here can be thought of as a proteomic map for either Flor or conventional Yeasts which can be useful to understand how these strains metabolize the sugars and release pleasant volatiles under sparkling wine elaboration conditions.

  • A Differential Proteomic Approach to Characterize the Cell Wall Adaptive Response to CO2 Overpressure during Sparkling Wine-Making Process.
    Microorganisms, 2020
    Co-Authors: Juan Antonio Porras-agüera, Jaime Moreno-garcía, Juan C. Mauricio, Juan Antonio Moreno, Teresa García-martínez
    Abstract:

    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.

  • First Proteomic Approach to Identify Cell Death Biomarkers in Wine Yeasts during Sparkling Wine Production.
    Microorganisms, 2019
    Co-Authors: Juan Antonio Porras-agüera, Jaime Moreno-garcía, Juan C. Mauricio, Juan Antonio Moreno, Teresa García-martínez
    Abstract:

    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.

  • Use of a Flor yeast strain for the second fermentation of sparkling wines: Effect of endogenous CO2 over-pressure on the volatilome.
    Food Chemistry, 2019
    Co-Authors: Rafael Martínez-garcía, Juan C. Mauricio, Anna Puig-pujol, Juan Antonio Moreno, Yenifer Roldán-romero, Teresa García-martínez
    Abstract:

    Abstract Saccharomyces cerevisiae Flor yeast is used for the first time in sparkling wine-making. Twenty-six oenological variables and fifty-three volatile metabolites are quantified in the middle (P = 3 bar) and at the end (P = 6 bar) of the second fermentation, carried out in open and closed bottles. A heat-map of volatiles and the fingerprints obtained for ten chemical families and ten odorant series visualize the changes for each condition. Terpenes, fatty acids and volatile phenols increased their contents by pressure effect at the end of the study by 25.0, 7.8 and 2.2%, respectively. The remaining families decrease between 17.4% and 30.1% for furanic compounds and esters in the same stage. A Principal Component Analysis established that nine volatiles are mainly affected by pressure and five by fermentation stage. The use of ethanol-tolerant Flor Yeasts constitutes an innovative procedure for the enhancement of the sparkling wines diversification.

  • Comparative analysis of intracellular metabolites, proteins and their molecular functions in a Flor yeast strain under two enological conditions
    World Journal of Microbiology and Biotechnology, 2018
    Co-Authors: Jaime Moreno-garcía, Minami Ogawa, C. M. Lucy Joseph, Juan C. Mauricio, Juan Moreno, Teresa García-martínez
    Abstract:

    Flor Yeasts confer a wide range of organoleptic properties to Sherry-type wines during a process called “biological aging” that takes place after alcoholic fermentation. These kinds of Yeasts adapt to a biological aging condition by forming a biofilm known as “Flor velum” and by changing from fermentative to oxidative metabolism. It has been reported that some functions such as increase of cell surface hydrophobicity or changes to lipid metabolism are enhanced when Yeasts switch to biofilm lifestyle. Here, we attempt to reveal intracellular metabolites and protein molecular functions not documented before that are relevant in biofilm formation and in fermentation by an endometabolome and proteome screening. We report that at early stages of biofilm formation, Flor Yeasts accumulate mannose, trehalose, glycerol, oleic and stearic acids and synthesize high amounts of GTPases, glycosylases and lipoproteins. On the other hand, in early fermentation, Flor Yeasts rapidly consume glucose and phosphoric acid; and produce abundant proteins related to chromatin binding, transcription factors and methyl transferases.

Tahia Benitez - One of the best experts on this subject based on the ideXlab platform.

  • overexpression of stress related genes enhances cell viability and velum formation in sherry wine Yeasts
    Applied Microbiology and Biotechnology, 2013
    Co-Authors: Jesus Fierrorisco, Tahia Benitez, Ana Maria Rincon, Antonio C Codon
    Abstract:

    Flor formation and Flor endurance have been related to ability by Saccharomyces cerevisiae Flor Yeasts to resist hostile conditions such as oxidative stress and the presence of acetaldehyde and ethanol. Ethanol and acetaldehyde toxicity give rise to formation of reactive oxygen species (ROS) and loss of cell viability. Superoxide dismutases Sod1p and Sod2p and other proteins such as Hsp12p are involved in oxidative stress tolerance. In this study, genes SOD1, SOD2, and HSP12 were overexpressed in Flor yeast strains FJF206, FJF414 and B16. In the SOD1 and SOD2 transformant strains superoxide dismutases encoded by genes SOD1 and SOD2 increased their specific activity considerably as a direct result of overexpression of genes SOD1 and SOD2, indirectly, catalase, glutathione reductase, and glutathione peroxidase activities increased too. The HSP12 transformant strains showed higher levels of glutathione peroxidase and reductase activities. These transformant strains showed an increase in intracellular glutathione content, a reduction in peroxidized lipid concentration, and higher resistance to oxidative stress conditions. As a result, Flor formation by these strains took place more rapidly than by their parental strains, velum being thicker and with higher percentages of viable cells. In addition, a slight decrease in ethanol and glycerol concentrations, and an increase in acetaldehyde were detected in wines matured under velum formed by transformant strains, as compared to their parental strains. In the industry, velum formed by transformant strains with increased viability may result in acceleration of both metabolism and wine aging, thus reducing time needed for wine maturation.

  • selection of an autochthonous saccharomyces strain starter for alcoholic fermentation of sherry base wines
    Journal of Industrial Microbiology & Biotechnology, 2013
    Co-Authors: Maria Rodriguezpalero, Jesus Fierrorisco, Antonio C Codon, Tahia Benitez, Manuel J Valcarcel
    Abstract:

    Several indigenous Saccharomyces strains from musts were isolated in the Jerez de la Frontera region, at the end of spontaneous fermentation, in order to select the most suitable autochthonous yeast starter, during the 2007 vintage. Five strains were chosen for their oenological abilities and fermentative kinetics to elaborate a Sherry base wine. The selected autochthonous strains were characterized by molecular methods: electrophoretic karyotype and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) and by physiological parameters: fermentative power, ethanol production, sugar consumption, acidity and volatile compound production, sensory quality, killer phenotype, desiccation, and sulphur dioxide tolerance. Laboratory- and pilot-scale fermentations were conducted with those autochthonous strains. One of them, named J4, was finally selected over all others for industrial fermentations. The J4 strain, which possesses exceptional fermentative properties and oenological qualities, prevails in industrial fermentations, and becomes the principal biological agent responsible for winemaking. Sherry base wine, industrially manufactured by means of the J4 strain, was analyzed, yielding, together with its sensory qualities, final average values of 0.9 g/l sugar content, 13.4 % (v/v) ethanol content and 0.26 g/l volatile acidity content; apart from a high acetaldehyde production, responsible for the distinctive aroma of “Fino”. This base wine was selected for “Fino” Sherry elaboration and so it was fortified; it is at present being subjected to biological aging by the so-called “Flor” Yeasts. The “Flor” velum formed so far is very high quality. To the best of our knowledge, this is the first study covering from laboratory to industrial scale of characterization and selection of autochthonous starter intended for alcoholic fermentation in Sherry base wines. Since the 2010 vintage, the indigenous J4 strain is employed to industrially manufacture a homogeneous, exceptional Sherry base wine for “Fino” Sherry production.

  • Chapter 3 – Yeasts Used in Biologically Aged Wines
    Molecular Wine Microbiology, 2011
    Co-Authors: Tahia Benitez, Ana Maria Rincon, Antonio C Codon
    Abstract:

    Most biologically aged wines are fortified to a strength of at least 16% alcohol and then aged under a thick, rough, white layer of yeast known as Flor , formed by Yeasts belonging to the genus Saccharomyces . The formation of this film depends on numerous factors, including the presence of proteins known as adhesins on the cell surface. The main adhesin involved in Flor formation is encoded by Flo11 , and the mechanisms regulating its expression are complex. These proteins are highly hydrophobic and are responsible for cell-cell adhesion and the formation of a Flor that becomes progressively thicker and floats on the surface of the wine. Thanks to this Flor , the Yeasts that participate in biological aging are highly resistant to alcohol, acetaldehyde, oxidative stress, and other hostile conditions, and most of them remain metabolically active throughout the aging process. As the must used to make biologically aged wines is fortified when all the sugars have been fermented, Flor Yeasts have an exclusively aerobic metabolism. The combination of the Flor and the oxidative metabolism of the Yeasts that it comprises creates a reducing environment that determines many of the organoleptic characteristics of the resulting wine. The aging of wine under a Flor of Yeasts followed by the use of a unique dynamic aging system known as soleras and criaderas results in the production of excellent wines.

  • acetaldehyde and ethanol are responsible for mitochondrial dna mtdna restriction fragment length polymorphism rflp in Flor Yeasts
    Systematic and Applied Microbiology, 2002
    Co-Authors: Francisco Castrejon, Antonio C Codon, Beatriz Cubero, Tahia Benitez
    Abstract:

    Flor Yeasts grow and survive in fino sherry wine where the frequency of respiratory-deficient (petite) mutants is very low. Mitochondria from Flor Yeasts are highly acetaldehyde- and ethanol-tolerant, and resistant to oxidative stress. However, restriction fragment length polymorphism (RFLP) of mtDNA from Flor yeast populations is very high and reflects variability induced by the high concentrations of acetaldehyde and ethanol of sherry wine on mtDNA. mtDNA RFLP increases as the concentration of these compounds also increases, but is followed by a total loss of mtDNA in petite cells. Yeasts with functional mitochondria (grande) are target of continuous variability, so that Flor yeast mtDNA can evolve extremely rapidly and may serve as a reservoir of genetic diversity, whereas petite mutants are eventually eliminated because metabolism in sherry wine is oxidative.

  • metabolism of saccharomyces cerevisiae Flor Yeasts during fermentation and biological aging of fino sherry by products and aroma compounds
    American Journal of Enology and Viticulture, 1998
    Co-Authors: P Martinez, M J Valcarcel, L Pierez, Tahia Benitez
    Abstract:

    During the biological aging of the Fino sherry, the formation of aroma compounds takes place as a result of the oxidative metabolism of the Saccharomyces cerevisiae Flor Yeasts, which form a film on the surface of the wine. Yeasts consume some compounds such as ethanol, glycerol, organic acids (acetic, lactic, citric and succinic), and amino acids, including proline. At the same time, Yeasts produce other compounds, namely higher alcohols (isobutanol and isoamilic), acetaldehyde and acetoin. We have compared differences in aroma production according to parameters involved in winemaking such as enological techniques applied, selected yeast strains used, and length of the aging process. Fermentation of must enriched in solids and other components resulted in fino sherry with a lower volatile acidity and a higher concentration of acetaldehyde, isoamilic alcohols, and glycerol than decanted must. Furthermore, while ethanol consumption was higher in "sobretablas", other compounds, such as acetic acid or glycerol, were steadily consumed throughout the aging period. As far as the strains are concerned, S. cerevisiae (beticus) and S. cerevisiae (cheresiensis) were better at reducing the volatile acidity than S. cerevisiae ( montuliensis) , which consumed more ethanol and produced more acetaldehyde (mainly responsible for the typical flavor of sherries). These results make it possible to select the final organoleptic characteristics of the wine by means of applying the appropriate enological processes and/or selected strain.

Manuel Medina - One of the best experts on this subject based on the ideXlab platform.

  • Effect of "Saccharomyces cerevisiae" F12 on volatile compounds in wines at three different stages of industrial biological ageing
    Australian Journal of Grape and Wine Research, 2008
    Co-Authors: D. Muñoz, Manuel Medina, Rafael A Peinado, Juan Antonio Moreno
    Abstract:

    Background and Aims: Wines subjected to biological ageing for variable lengths of time were inoculated with Saccharomyces cerevisiae F12 and were microaerated in order to reduce their overall ageing time. Methods and Results: Volatile compounds as determined by gas chromatography (GC) and GC�mass spectrometry (MS) were grouped according to their aroma descriptors into nine odourant classes, which exhibited similar changes in wines obtained by traditional ageing, and in others inoculated with S. cerevisiae F12 and microaerated. A tasting panel found the wine previously aged for 2 years and inoculated with S. cerevisiae F12 to be of better quality than the identical wine subjected to no inoculation. Conclusion: Based on the results, the ageing time for wines previously aged under typical winery conditions for 0 and 2 years can be shortened by the inoculation of S. cerevisiae F12 Flor Yeasts. Significance of the Study: The biological ageing system used allows the production cost of fino wines to be reduced by shortening the ageing process.

  • aroma series as fingerprints for biological ageing in fino sherry type wines
    Journal of the Science of Food and Agriculture, 2007
    Co-Authors: Lourdes Moyano, Jose A Moreno, Manuel Medina
    Abstract:

    BACKGROUND: The contribution of Flor Yeasts and wood to the ageing of fino sherry type wines was studied by using capillary column gas chromatography to analyse 72 aroma compounds in wines subjected to biological ageing. The odour activity values (OAVs) for the different compounds were classified into eight odorant series that describe the aroma profile of these wines (fruity, chemical, balsamic, vegetable, fatty, empyreumatic, Floral and spicy). RESULTS: The fruity samples made up the major series followed by the fatty and spicy at the end of the ageing period. The application of a linear regression model to the OAVs for the different series revealed that the fruity series, which is related to the Flor Yeasts activity, and the spicy series, which includes the compounds released by wood, are those most closely representing the changes in the aroma of these wines during their ageing. CONCLUSIONS: The comparison of the OAVs for fruity and spicy series along the ageing period can be used to establish a balance between the aroma compounds contributed by the Flor Yeasts and those extracted from the wood. This balance should be particularly considered in works aimed at shortening the ageing time for these wines. Copyright © 2007 Society of Chemical Industry

  • Aroma series as fingerprints for biological ageing in fino sherry‐type wines
    Journal of the Science of Food and Agriculture, 2007
    Co-Authors: Lourdes Moyano, Jose A Moreno, Manuel Medina
    Abstract:

    BACKGROUND: The contribution of Flor Yeasts and wood to the ageing of fino sherry type wines was studied by using capillary column gas chromatography to analyse 72 aroma compounds in wines subjected to biological ageing. The odour activity values (OAVs) for the different compounds were classified into eight odorant series that describe the aroma profile of these wines (fruity, chemical, balsamic, vegetable, fatty, empyreumatic, Floral and spicy). RESULTS: The fruity samples made up the major series followed by the fatty and spicy at the end of the ageing period. The application of a linear regression model to the OAVs for the different series revealed that the fruity series, which is related to the Flor Yeasts activity, and the spicy series, which includes the compounds released by wood, are those most closely representing the changes in the aroma of these wines during their ageing. CONCLUSIONS: The comparison of the OAVs for fruity and spicy series along the ageing period can be used to establish a balance between the aroma compounds contributed by the Flor Yeasts and those extracted from the wood. This balance should be particularly considered in works aimed at shortening the ageing time for these wines. Copyright © 2007 Society of Chemical Industry

  • Retention of Browning Compounds by Yeasts Involved in the Winemaking of Sherry Type Wines
    Biotechnology Letters, 2005
    Co-Authors: Julieta Merida, Azahara Lopez-toledano, Trinidad Marquez, Carmen Millan, Jose M. Ortega, Manuel Medina
    Abstract:

    Wine model solutions were used to study the ability of dehydrated Yeasts to retain the brown products formed in the reaction between (+)-catechin and acetaldehyde. Saccharomyces cerevisiae races capensis and bayanus , two typical Flor Yeasts involved in the biological aging of sherry wines, had a higher capacity to retain coloured compounds than S. cerevisiae fermentative yeast. Of the Flor Yeasts, capensis exhibited a higher colour reduction capacity than bayanus . Such differences may account for the different rate at which browning compounds are removed at different times of year during the biological aging of wines.

  • aroma compounds as markers of the changes in sherry wines subjected to biological ageing
    Food Control, 2004
    Co-Authors: Jose A Moreno, Lourdes Moyano, Manuel Medina
    Abstract:

    Abstract Capillary-column gas chromatography was used to determine 63 aroma compounds in 9 very pale sherry wines, fino type, subjected to biological ageing under industrial conditions for 1, 3 and 5 years. The contents in aroma compounds were related to the wine ageing time by means of a simple linear regression model. The compounds that exhibited a high correlation coefficient ( r >0.90) and simultaneously a high odour impact value (OAV > 5) were additionally subjected to principal component analysis. The first component was found to account for 93.12% of the changes in such compounds during the biological ageing process. The greatest contributions to this component were those from sotolon and 1,1-diethoxyethane, both related to the acetaldehyde produced by the metabolism of Flor Yeasts, and Z -whisky lactone synthesized from its precursors extracted from the casks wood where the wines were aged. The use of these compounds as markers for biological ageing is advantageous because their changes in concentrations is taken into account as well as their odorant impact.

J M Ortega - One of the best experts on this subject based on the ideXlab platform.

  • influence of blending on the content of different compounds in the biological aging of sherry dry wines
    Journal of Agricultural and Food Chemistry, 2004
    Co-Authors: Teresa M Berlanga, Juan C. Mauricio, Carmen Millan, Rafael A Peinado, J M Ortega
    Abstract:

    Principal components analysis to examine the effect of blending (viz. the mixing and transfer of wine between cask rows in a “criaderas and solera” system) on metabolic activity in Flor Yeasts duri...

  • influence of aeration on the physiological activity of Flor Yeasts
    Journal of Agricultural and Food Chemistry, 2001
    Co-Authors: Teresa M Berlanga, Juan C. Mauricio, Cristina Atanasio, J M Ortega
    Abstract:

    The effect of periodic aeration on the physiological activity of a strain of Saccharomyces cerevisiae yeast during development of velum (Flor) and biological aging of Sherry wine of the Fino type w...

  • changes in nitrogen compounds in must and wine during fermentation and biological aging by Flor Yeasts
    Journal of Agricultural and Food Chemistry, 2001
    Co-Authors: Juan C. Mauricio, Carmen Millan, Eva Valero, J M Ortega
    Abstract:

    Urea, ammonium, and free amino acid contents were quantified in a must from Vitis vinifera cv. Pedro Ximenez grapes and in fermented wine and after a short aging of this wine by Saccharomyces cerevisiae race capensis yeast under variable oxygen availability conditions. The previous compounds were also determined in a wine in which the nitrogen source was depleted by the same race of Flor yeast (old wine) and also following the addition of ammonium ion, l-glutamic acid, and l-proline. Under specific conditions such as low oxygen level and the absence of some nutrients, the Yeasts release some amino acids including l-threonine, l-tryptophan, l-cysteine, and l-methionine to the medium. These amino acids must originate primarily in a de novo synthesis from ethanol that regenerates NAD(P)+. On the basis of these results, the Yeasts may be able to use amino acids not only as nitrogen sources but also as redox agents to balance the oxidation−reduction potential under conditions of restricted oxygen, when electro...

  • in vitro specific activities of alcohol and aldehyde dehydrogenases from two Flor Yeasts during controlled wine aging
    Journal of Agricultural and Food Chemistry, 1997
    Co-Authors: Juan C. Mauricio, Juan J Moreno, J M Ortega
    Abstract:

    Two Flor yeast strains of Saccharomyces cerevisiae (S. cerevisiae strains capensis and bayanus) which form velum on the surface of sherry wine during biological aging have been used. Aldehyde and alcohol (isoenzymes I and II) dehydrogenases were detected in vitro during the entire wine-aging process in the Flor yeast strains. All enzymatic activities decreased during the first 155 days of wine aging, and after this period, an increase was observed. Ethanol consumption in the wine and the specific activity of alcohol dehydrogenase I were independent of the S. cerevisiae strain. The greater activity of alcohol dehydrogenase II is directly related to the higher acetaldehyde production by S. cerevisiae race bayanus in the wine. This strain has a slower and prolonged growth in the Flor film, which permits a continued accumulation of acetaldehyde in the wine. The higher activity of aldehyde dehydrogenase in capensis strain during the Flor formation may be related to the production and consumption of large amoun...

Marilena Budroni - One of the best experts on this subject based on the ideXlab platform.

  • Study of the role of the covalently linked cell wall protein (Ccw14p) and yeast glycoprotein (Ygp1p) within biofilm formation in a Flor yeast strain.
    Fems Yeast Research, 2018
    Co-Authors: Jaime Moreno-garcía, Giacomo Zara, Juan C. Mauricio, Teresa García-martínez, Marilena Budroni
    Abstract:

    : Flor Yeasts are Saccharomyces cerevisiae strains noted by their ability to create a type of biofilm in the air-liquid interface of some wines, known as 'Flor' or 'velum', for which certain proteins play an essential role. Following a proteomic study of a Flor yeast strain, we deleted the CCW14 (covalently linked cell wall protein) and YGP1 (yeast glycoprotein) genes-codifying for two cell surface glycoproteins-in a haploid Flor yeast strain and we reported that both influence the weight of the biofilm as well as cell adherence (CCW14).

  • genomic signatures of adaptation to wine biological ageing conditions in biofilm forming Flor Yeasts
    Molecular Ecology, 2017
    Co-Authors: Frederic Bigey, Giacomo Zara, Marilena Budroni, Sandrine Mallet, Souhir Marsit, Pierre Gladieux, Virginie Galeote, Sylvie Dequin, Jeanluc Legras
    Abstract:

    The molecular and evolutionary processes underlying fungal domestication remain largely unknown despite the importance of fungi to bioindustry and for comparative adaptation genomics in eukaryotes. Wine fermentation and biological aging are performed by strains of S. cerevisiae with, respectively, pelagic fermentative growth on glucose, and biofilm aerobic growth utilizing ethanol. Here, we use environmental samples of wine and Flor Yeasts to investigate the genomic basis of yeast adaptation to contrasted anthropogenic environments. Phylogenetic inference and population structure analysis based on single nucleotide polymorphisms (SNPs) revealed a group of Flor Yeasts separated from wine Yeasts. A combination of methods revealed several highly differentiated regions between wine and Flor Yeasts, and analyses using codon-substitution models for detecting molecular adaptation identified sites under positive selection in the high affinity transporter gene ZRT1. The Cross Population Composite Likelihood Ratio (XP-CLR) revealed selective sweeps at three regions, including in the hexose transporter gene HXT7, the yapsin gene YPS6 and the membrane protein coding gene MTS27. Our analyses also revealed that the biological aging environment has led to the accumulation of numerous mutations in proteins from several networks, including Flo11 regulation and divalent metal transport. Together, our findings suggest that the tuning of FLO11 expression and zinc transport networks are a distinctive feature of the genetic changes underlying the domestication of Flor Yeasts. Our study highlights the multiplicity of genomic changes underlying yeast adaptation to man-made habitats, and reveals that Flor/wine yeast lineage can serve as a useful model for studying the genomics of adaptive divergence.

  • Genomic signatures of adaptation to wine biological ageing conditions in biofilm‐forming Flor Yeasts
    Molecular Ecology, 2017
    Co-Authors: Frederic Bigey, Giacomo Zara, Marilena Budroni, Sandrine Mallet, Souhir Marsit, Pierre Gladieux, Virginie Galeote, Sylvie Dequin, Jeanluc Legras
    Abstract:

    The molecular and evolutionary processes underlying fungal domestication remain largely unknown despite the importance of fungi to bioindustry and for comparative adaptation genomics in eukaryotes. Wine fermentation and biological aging are performed by strains of S. cerevisiae with, respectively, pelagic fermentative growth on glucose, and biofilm aerobic growth utilizing ethanol. Here, we use environmental samples of wine and Flor Yeasts to investigate the genomic basis of yeast adaptation to contrasted anthropogenic environments. Phylogenetic inference and population structure analysis based on single nucleotide polymorphisms (SNPs) revealed a group of Flor Yeasts separated from wine Yeasts. A combination of methods revealed several highly differentiated regions between wine and Flor Yeasts, and analyses using codon-substitution models for detecting molecular adaptation identified sites under positive selection in the high affinity transporter gene ZRT1. The Cross Population Composite Likelihood Ratio (XP-CLR) revealed selective sweeps at three regions, including in the hexose transporter gene HXT7, the yapsin gene YPS6 and the membrane protein coding gene MTS27. Our analyses also revealed that the biological aging environment has led to the accumulation of numerous mutations in proteins from several networks, including Flo11 regulation and divalent metal transport. Together, our findings suggest that the tuning of FLO11 expression and zinc transport networks are a distinctive feature of the genetic changes underlying the domestication of Flor Yeasts. Our study highlights the multiplicity of genomic changes underlying yeast adaptation to man-made habitats, and reveals that Flor/wine yeast lineage can serve as a useful model for studying the genomics of adaptive divergence.

  • a set of haploid strains available for genetic studies of saccharomyces cerevisiae Flor Yeasts
    Fems Yeast Research, 2016
    Co-Authors: Jeanluc Legras, Giacomo Zara, Sylvie Dequin, Marilena Budroni
    Abstract:

    Flor Yeasts of Saccharomyces cerevisiae have been extensively studied for biofilm formation, however the lack of specific haploid model strains has limited the application of genetic approaches such as gene knockout, allelic replacement and Quantitative Trait Locus mapping for the deciphering of the molecular basis of velum formation under biological ageing. The aim of this work was to construct a set of Flor isogenic haploid strains easy to manipulate genetically. The analysis of the allelic variations at 12 minisatellite loci of 174 Saccharomyces cerevisiae strains allowed identifying three Flor parental strains with different phylogenic positions. These strains were characterized for sporulation efficiency, growth on galactose, adherence to polystyrene, agar invasion, growth on wine and ability to develop a biofilm. Interestingly, the inability to grow on galactose was found associated with a frameshift in GAL4 gene that seems peculiar of Flor strains. From these wild Flor strains, isogenic haploid strains were constructed by deleting HO gene with a loxP-KanMX-loxP cassette followed by the removal of the kanamycin cassette. Haploid strains obtained were characterized for their phenotypic and genetic properties and compared with the parental strains. Preliminary results showed that the haploid strains represent new tools for genetic studies and breeding programs on biofilm formation.

  • l histidine inhibits biofilm formation and flo11 associated phenotypes in saccharomyces cerevisiae Flor Yeasts
    PLOS ONE, 2014
    Co-Authors: Marc Bou Zeidan, Giacomo Zara, Ilaria Maria Mannazzu, Marilena Budroni, Carlo Viti, Francesca Decorosi, Luciana Giovannetti, Severino Zara
    Abstract:

    Flor Yeasts of Saccharomyces cerevisiae have an innate diversity of FLO11 which codes for a highly hydrophobic and anionic cell-wall glycoprotein with a fundamental role in biofilm formation. In this study, 380 nitrogen compounds were administered to three S. cerevisiae Flor strains handling FLO11 alleles with different expression levels. S. cerevisiae strain S288c was used as the reference strain as it cannot produce FLO11p. The Flor strains generally metabolized amino acids and dipeptides as the sole nitrogen source, although with some exceptions regarding L-histidine and histidine containing dipeptides. L-histidine completely inhibited growth and its effect on viability was inversely related to FLO11 expression. Accordingly, L-histidine did not affect the viability of the Δflo11 and S288c strains. Also, L-histidine dramatically decreased air–liquid biofilm formation and adhesion to polystyrene of the Flor Yeasts with no effect on the transcription level of the FLO11 gene. Moreover, L-histidine modified the chitin and glycans content on the cell-wall of Flor Yeasts. These findings reveal a novel biological activity of L-histidine in controlling the multicellular behavior of Yeasts.