Search results for "cerevisiae"
showing 10 items of 760 documents
Mecanismos de percepción y de respuesta a bajas temperaturas en Saccharomyces cerevisiae
2014
A lo largo de los años, la levadura S. cerevisiae se ha convertido en organismo modelo tanto en la industria, como en el campo de la investigación básica, debido a sus características metabólicas y su fácil manipulación. Es conocido que, cuando la célula se enfrenta a una situación de estrés, debe modificar su fisiología para mantener la homeostasis celular. En el ámbito industrial, el aumento en la demanda de levaduras con características especiales, ha hecho patente la necesidad de nuevas cepas que se adecuen a los requerimientos y necesidades del consumidor. En esta línea, las estrategias de mejora y selección de cepas industriales se ven limitadas por el escaso conocimiento que disponem…
Improvement of xylose fermentation of Saccharomyces cerevisiae
2012
The increasing need of oil and the negative impacts of fossil fuels on climate change have motivated the research towards environmental friendly alternatives to diminish the use of fossil resources. Until today, bioethanol production and use has increased worldwide. The raw materials used today compete with food industry and conquently, the ethanol production from lignocellulose has been developed intensively. However, to make the processes economically competitive, also pentoses in lignocellulose should be fermented at high rate. Saccharomyces cerevisiae, alias baker’s yeast has an excellent ethanol production capacity but it can not naturally utilize xylose. Several xylose-utilizing S. ce…
Caracterización de los componentes genéticos y ambientales implicados en el envejecimiento de las levaduras vínicas
2012
La mayor parte de la fermentación vínica discurre cuando las células de la levadura Saccharomyces cerevisiae han dejado de dividirse. Así pues, la viabilidad en fase estacionaria, llamada longevidad cronológica (LC), es esencial para que la vinificación se lleve a buen término. En este trabajo de tesis doctoral, se han caracterizado diversos componentes ambientales y genéticos que influyen en la longevidad cronológica de las levaduras vínicas. En cuanto a los componentes ambientales, el incremento de la acidez y la temperatura del medio promueven el envejecimiento. Los polifenoles resveratrol y quercetina y los compuestos de dos carbonos que se producen durante la fermentación, afectan de m…
Xrn1 influence on gene transcription results from the combination of general effects on elongating RNA pol II and gene-specific chromatin configurati…
2020
mRNA homoeostasis is favoured by crosstalk between transcription and degradation machineries. Both the Ccr4-Not and the Xrn1-decaysome complexes have been described to influence transcription. While Ccr4-Not has been shown to directly stimulate transcription elongation, the information available on how Xrn1 influences transcription is scarce and contradictory. In this study we have addressed this issue by mapping RNA polymerase II (RNA pol II) at high resolution, using CRAC and BioGRO-seq techniques in Saccharomyces cerevisiae. We found significant effects of Xrn1 perturbation on RNA pol II profiles across the genome. RNA pol II profiles at 5ʹ exhibited significant alterations that were com…
A new set of DNA macrochips for the yeast Saccharomyces cerevisiae: features and uses
2004
The yeast Saccharomyces cerevisiae has been widely used for the implementation of DNA chip technologies. For this reason and due to the extensive use of this organism for basic and applied studies, yeast DNA chips are being used by many laboratories for expression or genomic analyses. While membrane arrays (macroarrays) offer several advantages, for many laboratories they are not affordable. Here we report that a cluster of four Spanish molecular-biology yeast laboratories, with relatively small budgets, have developed a complete set of probes for the genome of S. cerevisiae. These have been used to produce a new type of macroarray on a nylon surface. The macroarrays have been evaluated and…
Exclusion of Saccharomyces kudriavzevii from a wine model system mediated by Saccharomyces cerevisiae.
2010
This study investigated the competition and potential hybrid generation between the species Saccharomyces cerevisiae and S. kudriavzevii in a wine-model environment. Our main goal was to understand why S. kudriavzevii has not been found in wine fermentations whilst their hybrids are present. Auxotrophic mutants (Ura(-) and Lys(-)) were used to favour the selection of hybrids and to specifically differentiate the two species in mixed fermentations carried out at different temperatures (17 °C, 24 °C and 31 °C). Both yeasts showed a reduction in their maximum specific growth rates in mixed fermentations, indicating a clear antagonistic effect between the two microorganisms. Temperature played …
Cytotoksyczność wybranych metaloftalocyjanin wobec mikroorganizmów
2015
Dokonano przeglądu literatury w zakresie cytotoksyczności metaloftalocyjanin wobec mikroorganizmów. W pracy zwrócono uwagę przede wszystkim na właściwości fotosensybilizacyjne ftalocyjanin oraz metaloftalocyjanin, które mogą być wykorzystane w terapii fotodynamicznej (PDT) oraz w fotodynamicznej terapii skierowanej przeciwko mikroorganizmom (PACT). Wykazano, że metalo-ftalocyjaniny bez podstawników, jak i kompleksy z podstawnikami aksjalnymi i/lub peryferyjnymi (t.j. pirydyna, grupy sulfonowe lub aminowe), a także ftalocyjaniny kationowe mogą być skuteczne w zwalczaniu bakterii (S. aureus E. coli), grzybów (np. S. cerevisiae) oraz wirusów (HSV). Działanie tych związków zależy głównie od moż…
Molecular and Macromolecular Changes in Bottle-Aged White Wines Reflect Oxidative Evolution–Impact of Must Clarification and Bottle Closure
2018
This article is part of the Research Topic "The Chemistry of Wine Ageing" Adresse de correspondance: Institut Universitaire de la Vigne et du Vin, Dijon, France PMCID: PMC5897750; International audience; Chardonnay wines from Burgundy, obtained from musts with three levels of clarification (Low, Medium and High) during two consecutive vintages (2009 and 2010) and for two kinds of closures (screw caps and synthetic coextruded closures) were analyzed chemically and sensorially. Three bottles per turbidity level were opened in 2015 in order to assess the intensity of the reductive and/or oxidative aromas (REDOX sensory scores) by a trained sensory panel. The chemical analyses consisted in poly…
Purīnu šķērsbarošanās mākslīgās maizes rauga Saccharomyces cerevisiae sabiedrībās
2020
Maizes raugs Saccharomyces cerevisiae ir vienkāršs eikariotisku šūnu modeļorganisms ar ko iespējams pētīt procesus gan molekulārā, gan populāciju līmenī. Izmantojot maizes raugu ir iespējams modelēt dažādu eikariotisku organismu populāciju konkurenci ierobežotu resursu apstākļos. Tas savukārt attiecas uz praktiskiem biotehnoloģiskiem pielietojumiem pārtikas rūpniecībā, medicīnā un ekoloģiskiem pētījumiem. Mikroorganismu kokultivācijā notiek divu vai vairāku organismu kultivēšana izolēta vidē. Tas ir metode bioloģiskas sabiedrības un organismu konkurences pētīšanai laboratorijas apstākļos. Izmantojot maizes raugu Saccharomyces cerevisiae kā modeļorganismu var pētīt atsevišķu organismu mutual…
Utilizzo del pied de cuve fortificato per la fermentazione spontanea di vini rossi di qualità
2018
La fermentazione spontanea è un processo biologico incontrollato durante il quale molti lieviti e/o batteri potrebbero aumentare rapidamente in concentrazioni tali incidere negativamente sulla qualità del prodotto finale. A tal proposito, al fine di ottimizzare la crescita di lieviti con buone attitudini enologiche, si utilizza il metodo “pied de cuve”. Questa tecnica enologica è in grado di realizzare in una determinata massa di mosto dal volume ridotto, una fermentazione alcolica con un ceppo di lievito opportunamente inoculato o con ceppi di lieviti indigeni, naturalmente presenti nel mosto. Al fine di valorizzazione ed aumentare la diffusione di pratiche enologiche basate su un ridotto …