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1.
Int J Food Microbiol ; 416: 110681, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38490108

RESUMO

In recent years, the presence of molecules derived from aromatic amino acids in wines has been increasingly demonstrated to have a significant influence on wine quality and stability. In addition, interactions between different yeast species have been observed to influence these final properties. In this study, a screening of 81 yeast strains from different environments was carried out to establish a consortium that would promote the improvement of indolic compound levels in wine. Two strains, Saccharomyces uvarum and Saccharomyces eubayanus, with robust fermentative capacity were selected to be combined with a Saccharomyces cerevisiae strain with a predisposition towards the production of indolic compounds. Fermentation dynamics were studied in pure cultures, co-inoculations and sequential inoculations, analysing strain interactions and end-of-fermentation characteristics. Fermentations showing significant interactions were further analyzed for the resulting indolic compounds and aroma profile, with the aim of observing potential interactions and synergies resulting from the combination of different strains in the final wine. Sequential inoculation of S. cerevisiae after S. uvarum or S. eubayanus was observed to increase indolic compound levels, particularly serotonin and 3-indoleacetic acid. This study is the first to demonstrate how the formation of microbial consortia can serve as a useful strategy to enhance compounds with interesting properties in wine, paving the way for future studies and combinations.


Assuntos
Saccharomyces , Vinho , Vinho/análise , Saccharomyces cerevisiae/metabolismo , Triptofano/análise , Triptofano/metabolismo , Fermentação , Saccharomyces/metabolismo
2.
Sci Rep ; 14(1): 4844, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418660

RESUMO

About half of the 1.62 billion cases of anemia are because of poor diet and iron deficiency. Currently, the use of iron-enriched yeasts can be used as the most effective and possible way to prevent and treat anemia due to the ability of biotransformation of mineral compounds into the organic form. In this research, for the first time, Saccharomyces (S.) boulardii was used for iron enrichment with the aim that the probiotic properties of yeast provide a potential iron supplement besides improving the bioavailability of iron. Also, due to its higher resistance than other Saccharomyces strains against stresses, it can protect iron against processing temperatures and stomach acidic-enzymatic conditions. So, the effect of three important variables, including concentration of iron, molasses and KH2PO4 on the growth and biotransformation of yeast was investigated by the Box-Behnken design (BBD). The best conditions occurred in 3 g/l KH2PO4, 20 g/l molasses and 12 mg/l FeSO4 with the highest biotransformation 27 mg Fe/g dry cell weight (DCW) and 6 g/l biomass weight. Such yeast can improve fermented products, provide potential supplement, and restore the lost iron of bread, which is a useful iron source, even for vegetarians-vegans and play an important role in manage with anemia. It is recommended that in future researches, attention should be paid to increasing the iron enrichment of yeast through permeabilizing the membrane and overcoming the structural barrier of the cell wall.


Assuntos
Anemia , Probióticos , Saccharomyces boulardii , Saccharomyces , Saccharomyces cerevisiae/metabolismo , Ferro/metabolismo , Saccharomyces/metabolismo , Probióticos/metabolismo
3.
J Sci Food Agric ; 104(7): 4136-4144, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38258891

RESUMO

BACKGROUND: Selenium is an important nutritional supplement that mainly exists naturally in soil as inorganic selenium. Saccharomyces cerevisiae cells are excellent medium for converting inorganic selenium in nature into organic selenium. RESULTS: Under the co-stimulation of sodium selenite (Na2SeO3) and potassium selenite (K2SeO3), the activity of selenophosphate synthetase (SPS) was improved up to about five folds more than conventional Na2SeO3 group with the total selenite salts content of 30 mg/L. Transcriptome analysis first revealed that due to the sharing pathway between sodium ion (Na+) and potassium ion (K+), the K+ largely regulates the metabolisms of amino acid and glutathione under the accumulation of selenite salt. Furthermore, K+ could improve the tolerance performance and selenium-biotransformation yields of Saccharomyces cerevisiae cells under Na2SeO3 salt stimulation. CONCLUSION: The important role of K+ in regulating the intracellular selenium accumulation especially in terms of amino acid metabolism and glutathione, suggested a new direction for the development of selenium-enrichment supplements with Saccharomyces cerevisiae cell factory. © 2024 Society of Chemical Industry.


Assuntos
Saccharomyces , Selênio , Selênio/metabolismo , Saccharomyces/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Selenito de Sódio/metabolismo , Ácido Selenioso/metabolismo , Glutationa/metabolismo , Sódio/metabolismo , Aminoácidos/metabolismo , Potássio/metabolismo
4.
J Agric Food Chem ; 71(41): 15417-15428, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37814909

RESUMO

Yeast flocculation and viability are critical factors in beer production. Adequate flocculation of yeast at the end of fermentation helps to reduce off-flavors and cell separation, while high viability is beneficial for yeast reuse. In this study, we used comparative genomics to analyze the genome information on Saccharomyces pastorianus W01, and its spontaneous mutant W02 with appropriate weakened flocculation ability (better off-flavor reduction performance) and unwanted decreased viability, to investigate the effect of different gene expressions on yeast flocculation or/and viability. Our results indicate that knockout of CNE1, CIN5, SIN3, HP-3, YPR170W-B, and SCEPF1_0274000100 and overexpression of CNE1 and ALD2 significantly decreased the flocculation ability of W01, while knockout of EPL1 increased the flocculation ability of W01. Meanwhile, knockout of CIN5, YPR170W-B, OST5, SFT1, SCEPF1_0274000100, and EPL1 and overexpression of SWC3, ALD2, and HP-2 decreased the viability of W01. CIN5, EPL1, SCEPF1_0274000100, ALD2, and YPR170W-B have all been shown to affect yeast flocculation ability and viability.


Assuntos
Saccharomyces cerevisiae , Saccharomyces , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Floculação , Saccharomyces/genética , Saccharomyces/metabolismo , Genômica , Cerveja/análise , Fermentação
5.
Food Microbiol ; 115: 104321, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37567631

RESUMO

Selection of the appropriate yeast strain is one of the most crucial steps in a brewery. Traditionally, yeast strain's abilities during beer fermentation are described according to brewer's experiences. Hence, these descriptions could be inaccurate and strictly based on sensory experiences. In this study, lager beers fermented by four traditional bottom-fermented yeast strains were characterized in detail by sensomic approach. The obtained results revealed that yeast strains can influence most of the sensory-related components in beer, not only esters and higher alcohols, but also carbonyls, amino acids, saccharides, fatty acids, heterocyclic compounds, hop oils, and other hop-related components. By comparison of chemical and sensory characteristics of each studied beer, the theoretical importance of sensory interactions on beer flavor perception was also revealed as the general conception that the beers with similar flavors have also similar chemical profiles (and vice versa) was seemed as not valid.


Assuntos
Saccharomyces cerevisiae , Saccharomyces , Saccharomyces cerevisiae/metabolismo , Cerveja/análise , Saccharomyces/metabolismo , Fermentação
6.
Microb Biotechnol ; 16(9): 1858-1871, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37449952

RESUMO

Erythritol is produced in yeasts via the reduction of erythrose into erythritol by erythrose reductases (ERs). However, the genes codifying for the ERs involved in this reaction have not been described in any Saccharomyces species yet. In our laboratory, we recently showed that, during alcoholic fermentation, erythritol is differentially produced by Saccharomyces cerevisiae and S. uvarum species, the latter being the largest producer. In this study, by using BLAST analysis and phylogenetic approaches the genes GRE3, GCY1, YPR1, ARA1 and YJR096W were identified as putative ERs in Saccharomyces cerevisiae Then, these genes were knocked out in our S. uvarum strain (BMV58) with higher erythritol biosynthesis compared to control S. cerevisiae wine strain, to evaluate their impact on erythritol synthesis and global metabolism. Among the mutants, the single deletion of GRE3 markedly impacts erythritol production, although ΔYPR1ΔGCY1ΔGRE3 was the combination that most decreased erythritol synthesis. Consistent with the increased production of fermentative by-products involved in redox balance in the Saccharomyces uvarum strain BMV58, erythritol synthesis increases at higher sugar concentrations, hinting it might be a response to osmotic stress. However, the expression of GRE3 in the S. uvarum strain was found to peak just before the start of the stationary phase, being consistent with the observation that erythritol increases at the start of the stationary phase, when there is low sugar in the medium and nitrogen sources are depleted. This suggests that GRE3 plays its primary function to help the yeast cells to maintain the redox balance during the last phases of fermentation.


Assuntos
Eritritol , Saccharomyces , Eritritol/metabolismo , Fermentação , Homeostase , Osmorregulação , Oxirredução , Filogenia , Saccharomyces/genética , Saccharomyces/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Açúcares/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo
7.
Biotechnol J ; 18(11): e2300240, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37522392

RESUMO

Ribonucleic acid (RNA) and its degradation products are important biomolecules widely used in the food and pharmaceutical industries for their flavoring and nutritional functions. In this study, we used a genome-scale metabolic network model (GSMM) to explore genetic targets for nucleic acid synthesis in a Saccharomyces pastorianus strain (G03). Yeast 8.5.0 was used as the base model, which accurately predicted G03's growth. Using OptForce, we found that overexpression of ARO8 and ATP1 among six different strategies increased the RNA content of G03 by 58.0% and 74.8%, respectively. We also identified new metabolic targets for improved RNA production using a modified GSMM called TissueModel, constructed using the GIMME transcriptome constraint tool to remove low-expressed reactions in the model. After running OptKnock, the RNA content of G03-△BNA1 and G03-△PMA1 increased by 44.6% and 39.8%, respectively, compared to G03. We suggest that ATP1, ARO8, BNA1, and PMA1 regulate cell fitness, which affects RNA content. This study is the first to identify strategies for RNA overproduction using GSMM and to report that regulation of ATP1, ARO8, BNA1, and PMA1 can increase RNA content in S. pastorianus. These findings also provide valuable knowledge on model reconstruction for S. pastorianus.


Assuntos
RNA , Saccharomyces , RNA/metabolismo , Genoma Fúngico/genética , Saccharomyces/genética , Saccharomyces/metabolismo , Saccharomyces cerevisiae/genética , Redes e Vias Metabólicas , Fermentação
9.
Microb Cell Fact ; 22(1): 109, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37287064

RESUMO

The probiotic yeast Saccharomyces boulardii (Sb) is a promising chassis to deliver therapeutic proteins to the gut due to Sb's innate therapeutic properties, resistance to phage and antibiotics, and high protein secretion capacity. To maintain therapeutic efficacy in the context of challenges such as washout, low rates of diffusion, weak target binding, and/or high rates of proteolysis, it is desirable to engineer Sb strains with enhanced levels of protein secretion. In this work, we explored genetic modifications in both cis- (i.e. to the expression cassette of the secreted protein) and trans- (i.e. to the Sb genome) that enhance Sb's ability to secrete proteins, taking a Clostridioides difficile Toxin A neutralizing peptide (NPA) as our model therapeutic. First, by modulating the copy number of the NPA expression cassette, we found NPA concentrations in the supernatant could be varied by sixfold (76-458 mg/L) in microbioreactor fermentations. In the context of high NPA copy number, we found a previously-developed collection of native and synthetic secretion signals could further tune NPA secretion between 121 and 463 mg/L. Then, guided by prior knowledge of S. cerevisiae's secretion mechanisms, we generated a library of homozygous single gene deletion strains, the most productive of which achieved 2297 mg/L secretory production of NPA. We then expanded on this library by performing combinatorial gene deletions, supplemented by proteomics experiments. We ultimately constructed a quadruple protease-deficient Sb strain that produces 5045 mg/L secretory NPA, an improvement of > tenfold over wild-type Sb. Overall, this work systematically explores a broad collection of engineering strategies to improve protein secretion in Sb and highlights the ability of proteomics to highlight under-explored mediators of this process. In doing so, we created a set of probiotic strains that are capable of delivering a wide range of protein titers and therefore furthers the ability of Sb to deliver therapeutics to the gut and other settings to which it is adapted.


Assuntos
Probióticos , Saccharomyces boulardii , Saccharomyces , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces boulardii/genética , Saccharomyces boulardii/metabolismo , Saccharomyces/genética , Saccharomyces/metabolismo , Probióticos/metabolismo , Endopeptidases/metabolismo
10.
Food Microbiol ; 113: 104270, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37098430

RESUMO

Saccharomyces cerevisiae is the yeast of choice for most inoculated wine fermentations worldwide. However, many other yeast species and genera display phenotypes of interest that may help address the environmental and commercial challenges the wine industry has been facing in recent years. This work aimed to provide, for the first time, a systematic phenotyping of all Saccharomyces species under winemaking conditions. For this purpose, we characterized the fermentative and metabolic properties of 92 Saccharomyces strains in synthetic grape must at two different temperatures. The fermentative potential of alternative yeasts was higher than expected, as nearly all strains were able to complete fermentation, in some cases more efficiently than commercial S. cerevisiae strains. Various species showed interesting metabolic traits, such as high glycerol, succinate and odour-active compound production, or low acetic acid production, compared to S. cerevisiae. Altogether, these results reveal that non-cerevisiae Saccharomyces yeasts are especially interesting for wine fermentation, as they may offer advantages over both S. cerevisiae and non-Saccharomyces strains. This study highlights the potential of alternative Saccharomyces species for winemaking, paving the way for further research and, potentially, for their industrial exploitation.


Assuntos
Saccharomyces , Vitis , Vinho , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fermentação , Saccharomyces/genética , Saccharomyces/metabolismo , Vinho/análise , Vitis/metabolismo , Ácido Acético/metabolismo , Fenótipo
11.
Elife ; 122023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36848406

RESUMO

Bone destruction is a hallmark of chronic inflammation, and bone-resorbing osteoclasts arising under such a condition differ from steady-state ones. However, osteoclast diversity remains poorly explored. Here, we combined transcriptomic profiling, differentiation assays and in vivo analysis in mouse to decipher specific traits for inflammatory and steady-state osteoclasts. We identified and validated the pattern-recognition receptors (PRR) Tlr2, Dectin-1, and Mincle, all involved in yeast recognition as major regulators of inflammatory osteoclasts. We showed that administration of the yeast probiotic Saccharomyces boulardii CNCM I-745 (Sb) in vivo reduced bone loss in ovariectomized but not sham mice by reducing inflammatory osteoclastogenesis. This beneficial impact of Sb is mediated by the regulation of the inflammatory environment required for the generation of inflammatory osteoclasts. We also showed that Sb derivatives as well as agonists of Tlr2, Dectin-1, and Mincle specifically inhibited directly the differentiation of inflammatory but not steady-state osteoclasts in vitro. These findings demonstrate a preferential use of the PRR-associated costimulatory differentiation pathway by inflammatory osteoclasts, thus enabling their specific inhibition, which opens new therapeutic perspectives for inflammatory bone loss.


Assuntos
Osteoporose , Probióticos , Animais , Camundongos , Osteogênese , Osteoporose/terapia , Receptor 2 Toll-Like , Saccharomyces/genética , Saccharomyces/metabolismo
12.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36694952

RESUMO

Microbial growth requires energy for maintaining the existing cells and producing components for the new ones. Microbes therefore invest a considerable amount of their resources into proteins needed for energy harvesting. Growth in different environments is associated with different energy demands for growth of yeast Saccharomyces cerevisiae, although the cross-condition differences remain poorly characterized. Furthermore, a direct comparison of the energy costs for the biosynthesis of the new biomass across conditions is not feasible experimentally; computational models, on the contrary, allow comparing the optimal metabolic strategies and quantify the respective costs of energy and nutrients. Thus in this study, we used a resource allocation model of S. cerevisiae to compare the optimal metabolic strategies between different conditions. We found that S. cerevisiae with respiratory-impaired mitochondria required additional energetic investments for growth, while growth on amino acid-rich media was not affected. Amino acid supplementation in anaerobic conditions also was predicted to rescue the growth reduction in mitochondrial respiratory shuttle-deficient mutants of S. cerevisiae. Collectively, these results point to elevated costs of resolving the redox imbalance caused by de novo biosynthesis of amino acids in mitochondria. To sum up, our study provides an example of how resource allocation modeling can be used to address and suggest explanations to open questions in microbial physiology.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces , Saccharomyces cerevisiae/metabolismo , Saccharomyces/metabolismo , Biomassa , Mitocôndrias/metabolismo , Aminoácidos/metabolismo , Respiração , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
13.
J Agric Food Chem ; 71(5): 2493-2502, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36693141

RESUMO

In Saccharomyces, the IRC7 gene encodes for a cysteine S-conjugate ß-lyase enzyme which can release polyfunctional thiols from their cysteinylated precursor forms, thereby promoting thiol aroma in beer. This study examined the thiol production of 10 commercial yeast strains in two different media, a hopped yeast extract-peptone-dextrose (YPD) medium and a 100% barley malt wort to explore how differences in yeast strain and medium conditions influence the release of polyfunctional thiols. 3-Sulfanylhexan-1-ol was most affected by medium conditions, and its concentrations were highest in wort fermentations. The higher nitrogen content and pH of the YPD medium relative to the wort fermentations were notable differences, and significant correlations between these variables and the extent of free thiol production were observed. A strong association existed between polyfunctional thiol concentrations and the fermentation-derived, malt, and hop-derived compounds 2-phenylethanol, ß-damascenone, and ß-ionone. The sensory impressions of thiol character in beer were influenced by the presence of other aromatic compounds such as esters and terpene alcohols, and aroma attributes such as "tropical" were not the most suitable for describing beers brewed with yeasts that fully express homozygous IRC7F. Sensory attributes "sweaty", "vegetal", and "overripe fruit" were more strongly associated with these strains.


Assuntos
Odorantes , Saccharomyces , Odorantes/análise , Fermentação , Compostos de Sulfidrila/metabolismo , Leveduras/metabolismo , Saccharomyces/metabolismo , Cerveja/análise
14.
Prep Biochem Biotechnol ; 53(5): 511-522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35981094

RESUMO

L-asparaginase (ASNase) is an efficient inhibitor of tumor development, used in chemotherapy sessions against acute lymphoblastic leukemia (ALL) tumor cells; its use results in 80% complete remission of the disease in treated patients. Saccharomyces cerevisiae's L-asparaginase II (ScASNaseII) has a high potential to substitute bacteria ASNase in patients that developed hypersensitivity, but the endogenous production of it results in hypermannosylated immunogenic enzyme. Here we describe the genetic process to acquire the ScASNaseII expressed in the extracellular medium. Our strategy involved a fusion of mature sequence of protein codified by ASP3 (amino acids 26-362) with the secretion signal sequence of Pichia pastoris acid phosphatase enzyme; in addition, this DNA construction was integrated in P. pastoris Glycoswitch® strain genome, which has the cellular machinery to express and secrete high quantity of enzymes with humanized glycosylation. Our data show that the DNA construction and strain employed can express extracellular asparaginase with specific activity of 218.2 IU mg-1. The resultant enzyme is 40% more stable than commercially available Escherichia coli's ASNase (EcASNaseII) when incubated with human serum. In addition, ScASNaseII presents 50% lower cross-reaction with anti-ASNase antibody produced against EcASNaseII when compared with ASNase from Dickeya chrysanthemi.


Assuntos
Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Saccharomyces , Humanos , Asparaginase/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Antineoplásicos/farmacologia
15.
Microb Biotechnol ; 15(12): 2958-2969, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36307988

RESUMO

The use of unconventional yeast species in human-driven fermentations has attracted a lot of attention in the last few years. This tool allows the alcoholic beverage industries to solve problems related to climate change or the consumer demand for newer high-quality products. In this sense, one of the most attractive species is Saccharomyces kudriavzevii, which shows interesting fermentative traits such as the increased and diverse aroma compound production in wines. Specifically, it has been observed that different isolates of this species can produce higher amounts of higher alcohols such as phenylethanol compared with Saccharomyces cerevisiae. In this work, we have shed light on this feature relating it to the S. kudriavzevii aromatic amino acid anabolic pathway in which the enzyme Aro4p plays an essential role. Unexpectedly, we observed that the presence of the S. kudriavzevii ARO4 variant reduces phenylethanol production compared with the S. cerevisiae ARO4 allele. Our experiments suggest that this can be explained by increased feedback inhibition, which might be a consequence of the changes detected in the Aro4p amino end such as L26 Q24 that have been under positive selection in the S. kudriavzevii specie.


Assuntos
Álcool Feniletílico , Saccharomyces , Vinho , Humanos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Álcoois/metabolismo , Saccharomyces/genética , Saccharomyces/metabolismo , Vinho/análise , Fermentação , Álcool Feniletílico/metabolismo
16.
BMC Vet Res ; 18(1): 178, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568841

RESUMO

BACKGROUND: The adverse effect of aflatoxin in broilers is well known. However, dietary supplementation of Saccharomyces cell wall and/or Nanocurcumin may decrease the negative effect of aflatoxin B1 because of the bio-adsorbing feature of the functional ingredients in Yeast Cell Wall and the detoxification effect of curcumin nanoparticles. The goal of this study was to see how Saccharomyces cell wall/Nanocurcumin alone or in combination with the aflatoxin-contaminated diet ameliorated the toxic effects of aflatoxin B1 on broiler development, blood and serum parameters, carcass traits, histology, immune histochemistry, liver gene expression, and aflatoxin residue in the liver and muscle tissue of broilers for 35 days. Moreover, the withdrawal time of aflatoxin was measured after feeding the aflatoxicated group an aflatoxin-free diet. Broiler chicks one day old were distributed into five groups according to Saccharomyces cell wall and/or nanocurcumin with aflatoxin supplementation. The G1 group was given a formulated diet without any supplements. The G2 group was supplemented with aflatoxin (0.25 mg/kg diet) in the formulated diet. The G3 group was supplemented with aflatoxin (0.25 mg/kg diet) and Saccharomyces cell wall (1 kg/ton diet) in the formulated diet. The G4 group was supplemented with aflatoxin (0.25 mg/kg diet) and nanocurcumin (400 mg/kg) in the formulated diet. The G5 group was supplemented with aflatoxin (0.25 mg/kg diet) and Saccharomyces cell wall (1 kg/ton diet) in combination with nanocurcumin (200 mg/kg) in the formulated diet. RESULTS: According to the results of this study, aflatoxin supplementation had a detrimental impact on the growth performance, blood and serum parameters, carcass traits, and aflatoxin residue in the liver and muscle tissue of broilers. In addition, aflatoxin supplementation led to a liver injury that was indicated by serum biochemistry and pathological lesions in the liver tissue. Moreover, the shortening of villi length in aflatoxicated birds resulted in a decrease in both the crypt depth ratio and the villi length ratio. The expression of CYP1A1 and Nrf2 genes in the liver tissue increased and decreased, respectively, in the aflatoxicated group. In addition, the aflatoxin residue was significantly (P ≤ 0.05) decreased in the liver tissue of the aflatoxicated group after 2 weeks from the end of the experiment. CONCLUSION: Saccharomyces cell wall alone or with nanocurcumin attenuated these negative effects and anomalies and improved all of the above-mentioned metrics.


Assuntos
Aflatoxinas , Doenças Transmitidas por Alimentos , Saccharomyces , Aflatoxina B1/metabolismo , Aflatoxina B1/toxicidade , Aflatoxinas/toxicidade , Ração Animal/análise , Animais , Parede Celular/metabolismo , Galinhas , Dieta/veterinária , Suplementos Nutricionais , Doenças Transmitidas por Alimentos/veterinária , Saccharomyces/metabolismo
17.
Food Microbiol ; 104: 103981, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35287810

RESUMO

Saccharomyces yeasts from different origins and species fermented in a semi-synthetic must containing aroma precursor of cv. Albariño and polyfunctional mercaptans precursors. The resulting wines were subjected to accelerate anoxic aging. Afterward, aroma profiles were analyzed by distinct gas chromatography methodologies. Cryotolerant strains showed better fermentation performances with significant differences in volatile and non-volatile fermentation products than Saccharomyces cerevisiae (S. cerevisiae). We suggested that the highest levels γ-butyrolactone and diethyl succinate in Saccharomyces uvarum (S. uvarum) strains, together with their substantial succinic acid yields, could be related to greater flux through the GABA shunt. These strains also had the highest production of ß-phenylethyl acetate, geraniol, and branched-chain ethyl esters. The latter compounds were highly increased by aging, while acetates and some terpenes decreased. S. kudriavzevii strains showed a remarkable ability to release polyfunctional mercaptans, with SK1 strain yielding up to 47-fold and 8-fold more 4-methyl-4-mercaptopentan-2-one (4MMP) than S. cerevisiae and S. uvarum strains, respectively. The wild S. cerevisiae beer isolate showed a particular aroma profile due to the highest production of ethyl 4-methylvalerate (lactic and fruity notes), γ-octalactone (coconut), and furfurylthiol (roasted coffee). The latter compound is possibly produced from the pentose phosphate pathway (PPP). Since erythritol, another PPP intermediate was largely produced by this strain.


Assuntos
Saccharomyces , Vinho , Odorantes/análise , Saccharomyces/metabolismo , Saccharomyces cerevisiae/metabolismo , Vinho/análise
18.
Curr Microbiol ; 79(4): 120, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35235071

RESUMO

To clarify the lethal injury related to the inactivation of Saccharomyces pastorianus cells by low-pressure carbon dioxide microbubble (CO2MB) treatment, surviving number, leakage of nucleic acids and proteins, fluorescence polarisation (FP) of the cell membrane, activity of alkaline phosphatase (AP), intracellular pH (pHin), mitochondrial membrane potential (MMP), cell surface hydrophobicity (CSH) and oxidative stress of S. pastorianus treated with CO2MB at various temperatures were measured. The number of surviving S. pastorianus cells decreased below the detection limit after CO2MB treatment at temperatures of 40, 45 and 50 â„ƒ, inducing a 2-log reduction at 35 â„ƒ. The S. pastorianus cells treated with CO2MB at temperatures above 40 â„ƒ showed an increase in FP and leakage of nucleic acids and proteins. The AP in S. pastorianus cells treated with CO2MB at a temperature of 35 â„ƒ was also activated but inactivated at temperatures above 40 â„ƒ. Furthermore, the decrease in pHin and MMP and the increase in CSH of S. pastorianus were caused by CO2MB treatment at temperatures above 35 â„ƒ. Oxidative stress in S. pastorianus cells was also increased by CO2MB treatment without warming but decreased at temperatures above 35 â„ƒ. Our results lead us to infer that the type of cell injury in S. pastorianus induced by CO2MB treatment differed from that caused by the treatment temperature and that the lethal injury was enzyme inactivation.


Assuntos
Dióxido de Carbono , Saccharomyces , Dióxido de Carbono/metabolismo , Fermentação , Microbolhas , Saccharomyces/metabolismo
19.
Cells ; 11(4)2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35203287

RESUMO

Saccharomyces uvarum is one of the few fermentative species that can be used in winemaking, but its weak sulfite tolerance is the main reason for its further use. Previous studies have shown that the expression of the methionine synthase gene (MET4) is upregulated in FZF1 (a gene encoding a putative zinc finger protein, which is a positive regulator of the transcription of the cytosolic sulfotransferase gene SSU1) overexpression transformant strains, but its exact function is unknown. To gain insight into the function of the MET4 gene, in this study, a MET4 overexpression vector was constructed and transformed into S. uvarum strain A9. The MET4 transformants showed a 20 mM increase in sulfite tolerance compared to the starting strain. Ninety-two differential genes were found in the transcriptome of A9-MET4 compared to the A9 strain, of which 90 were upregulated, and two were downregulated. The results of RT-qPCR analyses confirmed that the expression of the HOMoserine requiring gene (HOM3) in the sulfate assimilation pathway and some fermentation-stress-related genes were upregulated in the transformants. The overexpression of the MET4 gene resulted in a significant increase in sulfite tolerance, the upregulation of fermentation-stress-related gene expression, and significant changes in the transcriptome profile of the S. uvarum strain.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Proteínas Fúngicas , Saccharomyces , Sulfitos , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Saccharomyces/genética , Saccharomyces/metabolismo , Sulfitos/metabolismo , Regulação para Cima
20.
PLoS Genet ; 17(11): e1009872, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34762651

RESUMO

Different species can find convergent solutions to adapt their genome to the same evolutionary constraints, although functional convergence promoted by chromosomal rearrangements in different species has not previously been found. In this work, we discovered that two domesticated yeast species, Saccharomyces cerevisiae, and Saccharomyces uvarum, acquired chromosomal rearrangements to convergently adapt to the presence of sulfite in fermentation environments. We found two new heterologous chromosomal translocations in fermentative strains of S. uvarum at the SSU1 locus, involved in sulfite resistance, an antimicrobial additive widely used in food production. These are convergent events that share similarities with other SSU1 locus chromosomal translocations previously described in domesticated S. cerevisiae strains. In S. uvarum, the newly described VIIXVI and XIXVI chromosomal translocations generate an overexpression of the SSU1 gene and confer increased sulfite resistance. This study highlights the relevance of chromosomal rearrangements to promote the adaptation of yeast to anthropic environments.


Assuntos
Adaptação Biológica/genética , Anti-Infecciosos/metabolismo , Fermentação , Conservantes de Alimentos/metabolismo , Saccharomyces cerevisiae/fisiologia , Saccharomyces/fisiologia , Sulfitos/metabolismo , Proteínas de Transporte de Ânions/genética , Cromossomos Fúngicos , Humanos , Filogenia , Regiões Promotoras Genéticas , Saccharomyces/genética , Saccharomyces/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Translocação Genética
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