Search results for " Saccharomyces"
showing 10 items of 42 documents
A nanodosimetric model of radiation-induced clustered DNA damage yields
2010
International audience; We present a nanodosimetric model for predicting the yield of double strand breaks (DSBs) and non-DSB clustered damages induced in irradiated DNA. The model uses experimental ionization cluster size distributions measured in a gas model by an ion counting nanodosimeter or, alternatively, distributions simulated by a Monte Carlo track structure code developed to simulate the nanodosimeter. The model is based on a straightforward combinatorial approach translating ionizations, as measured or simulated in a sensitive gas volume, to lesions in a DNA segment of one-two helical turns considered equivalent to the sensitive volume of the nanodosimeter. The two model paramete…
Strategie microbiologiche per la produzione di vini base ad elevata acidità da racemi della cultivar Grillo per l’ottenimento di spumanti siciliani
Sempre maggiore è l’importanza che stanno acquisendo gli spumanti Italiani nel mondo, ed anche la produzione vitivinicola in Sicilia è aumentata nell’ultimo decennio. Gli spumanti di qualità, però, sono caratterizzati da un’elevata acidità che non sempre è raggiunta nei vini base e negli spumanti prodotti nelle aree con climi caldo-temperati come quello siciliano. A tale scopo, si sono svolte delle fermentazioni su un mosto di racemi di Grillo, per l’ottenimento del vino di base spumante, avviando numerose attività di natura microbiologica, molecolare, chimico-fisica e sensoriale. I lieviti utilizzati come starter nelle fermentazioni, sono stati isolati da uve racemi raccolte nelle vendemmi…
AcetyltransferaseSAS2and sirtuinSIR2,respectively, control flocculation and biofilm formation in wine yeast
2014
Cell-to-cell and cell-to-environment interactions of microorganisms are of substantial relevance for their biotechnological use. In the yeast Saccharomyces cerevisiae, flocculation can be an advantage to clarify final liquid products after fermentation, and biofilm formation may be relevant for the encapsulation of strains of interest. The adhesion properties of wine yeast strains can be modified by the genetic manipulation of transcriptional regulatory proteins, such as histone deacetylases, and acetylases. Sirtuin SIR2 is essential for the formation of mat structures, a kind of biofilm that requires the expression of cell-wall protein FLO11 as its deletion reduces FLO11 expression, and ad…
Utilizzo alternativo dei frutti di vecchie varietà di melo siciliane mediante trasformazione in sidro
2010
Use of fortified pied de cuve as an innovative method to start spontaneous alcoholic fermentation for red winemaking
2016
Background and Aims: Some wineries, in order to promote the growth of yeasts able to ferment grape musts, traditionally produce wines using the ‘pied de cuve’ method. The aim of the present work was to study the performance of fortified pied de cuve (FPdC) prepared by addition of wine. Method and Results: Two FPdCs were prepared with the addition of wine at 1.5 and 3% (v/v) of ethanol to the musts and allowed to spontaneously ferment. The FPdCs were then added to fresh bulk musts in order to accelerate the spontaneous alcoholic fermentation (AF). Interestingly, several Saccharomyces cerevisiae strains isolated during the pied de cuve preparation were detected at the highest concentration th…
Chromatin modifiers and recombination factors promote a telomere fold-back structure, that is lost during replicative senescence.
2020
Telomeres have the ability to adopt a lariat conformation and hence, engage in long and short distance intra-chromosome interactions. Budding yeast telomeres were proposed to fold back into subtelomeric regions, but a robust assay to quantitatively characterize this structure has been lacking. Therefore, it is not well understood how the interactions between telomeres and non-telomeric regions are established and regulated. We employ a telomere chromosome conformation capture (Telo-3C) approach to directly analyze telomere folding and its maintenance in S. cerevisiae. We identify the histone modifiers Sir2, Sin3 and Set2 as critical regulators for telomere folding, which suggests that a dis…
Enological Repercussions of Non-Saccharomyces Species
2019
The bulk of the sugar fermentation in grape juice, in order to produce wine is carried out by yeasts of the genus Saccharomyces, mainly S. cerevisiae. However, S. cerevisiae is not the only wine yeast, as spontaneous grape juice fermentation involves a complex succession of growth and death of different yeasts [1,2], and each of them contribute to the organoleptic properties of the final product. Saccharomyces are not usually found in the epiphytic yeasts present on the surface of grapes, where Hanseniaspora, Candida, Pichia, and Hansenula are dominant [3]. However, Saccharomyces imposes itself due to its higher tolerance to the stressful conditions of fermentation, due to its resistance to…
Investigation of yeast community of “Grillo” grapes and musts from Marsala wine production area.
2009
The oenological interest in the autochthonous yeast applications has increased since they represents an important supplement to wine quality (Martinez et al. 1989; Moreno et al. 1991). Yeast populations harboured onto the surface of berries and in musts of “Grillo” grape variety were isolated and analyzed. In order to obtain a first blastomycetic mapping of Marsala wine production area, eight vineyards were chosen on the basis of different climatic and agronomic parameters, including altitude, exposure,vineyard age, grape biotype, grape cultivation system, vegetative vigour, pruning, green pruning, yield per plant, phytosanity state, irrigation and closeness to wood areas. Analysis of blast…
Ricerca di lieviti autoctoni per migliorare il profilo aromatico delle birre artigianali
2019
In corso d’opera un’analisi di matrici appartenenti a diverse nicchie ecologiche con l’obiettivo di individuare lieviti dalle caratteristiche tecnologiche e qualitative ottimali
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 …