Search results for "saccharomyces"

GC-MS as a tool to study the aromatic profiles of Candida zemplinina/ Saccharomyces cerevisiae mixed fermentation wines

2013

Regulated expression and phosphorylation of the 23-26-kDa ras protein in the sponge Geodia cydonium.

1990

We have cloned, sequenced and examined the sponge Geodia cydonium cDNA encoding a protein homologous to ras proteins. The sponge ras protein has a more conserved N-terminal region and a less conserved C-terminal region, especially in comparison to Dictyostelium discoideum; the similarity to human c-Ha-ras-1 and to Saccharomyces cerevisiae is less pronounced. The sponge ras cDNA comprises five TAG triplets; at the translational level these UAG termination codons are suppressed by a Gln-tRNA. The sponge ras protein was isolated and partially purified (23-26 kDa) and found to undergo phosphorylation at a threonine moiety, when dissociated cells were incubated in the presence of a homologous ag…

Ras-pathway has a dual role in yeast galactose metabolism

2007

AbstractIn the yeast Saccharomyces cerevisiae the genes involved in galactose metabolism (GAL1,7,10) are transcriptionally activated more than a 1000-fold in the presence of galactose as the sole carbon source in the culture media. In the present work, we monitored the activity of the GAL10 gene promoter in different Ras-cAMP genetic backgrounds. We demonstrate that overexpression of C-terminus of the nucleotide exchange factor Cdc25p stimulates GAL10 transcription in yeast strains carrying the contemporary deletion of both RAS genes. Moreover, the deletion of the chromosomal CDC25 gene provokes impaired growth on galactose based media in yeast strain lacking both RAS genes and adenylate cy…

Sch 9p kinase and the Gcn4p transcription factor regulate glycerol production during winemaking

2017

Grape juice fermentation is a harsh environment with many stressful conditions, and Saccharomyces cerevisiae adapts its metabolism in response to those environmental challenges. Many nutrient-sensing pathways control this feature. The Tor/Sch9p pathway promotes growth and protein synthesis when nutrients are plenty, while the transcription factor Gcn4p is required for the activation of amino acid biosynthetic pathways. We previously showed that Sch9p impact on longevity depends on the nitrogen/carbon ratio. When nitrogen is limiting, SCH9 deletion shortens chronological life span, which is the case under winemaking conditions. Its deletion also increases glycerol during fermentation, so the…

A Comparative Study of Different Methods of Yeast Strain Characterization

1992

Summary An extensive survey of different methods of yeast strain identification (classical microbiological tests, whole-cell protein electrophoresis, chromosomal patterns, DNA hybridization and mitochondrial DNA restriction analysis) has been carried out in order to differentiate, with industrial purposes, strains present in the Alicante wine ecosystem. Only chromosomal patterns and mitochondrial DNA (mtDNA) restriction analysis show differences between strains. Both techniques are very complex to be used in bio technological industries. For this reason, we have developed a new, simple, unexpensive and rapid method based on mtDNA restriction analysis.

A rapid and simple method for the preparation of yeast mitochondrial DNA

1990

Effect of α-factor on individual wall mannoproteins fromSaccharomyces cerevisiae acells

1985

Treatment of Saccharomyces cerevisiae a cells with α-factor partially inhibits mannosylation of the high Mr mannoproteins, although there is an increase in the total amount of these molecules present in the wall. They show a similar mobility in SDS-acrylamide gels to those from untreated mnn2 cells. No other significant effects on wall mannoproteins have been observed, except a decrease in the amount of the 29 kDa species.

Yeast dsRNA viruses: replication and killer phenotypes

1991

The cytoplasmic L-A dsRNA virus of Saccharomyces cerevisiae consists of a 4.5 kb dsRNA and the two gene products it encodes; the capsid (cap) and at least one copy of the capsid-polymerase (cap-pol) fusion protein. Virion cap-pol catalyses transcription of the plus (sense)-strand; this is extruded from the virus and serves as messenger for synthesis of cap and cap-pol. Nascent cap-pol binds to a specific domain in the plus strand to initiate encapsidation and then catalyses minus-strand synthesis to complete the replication cycle. Products of at least three host genes are required for replication, and virus copy number is kept at tolerable levels by the SKI antivirus system. S. cerevisiae k…

Basic phenotypic analysis of six novel yeast genes reveals two essential genes and one which affects the growth rate

1999

Phenotypic analysis was performed on six mutants of Saccharomyces cerevisiae deleted in one of the following open reading frames (ORFs), located on chromosome II: YBR254c, YBR255w, YBR257w, YBR258c, YBR259w and YBR266c. Disruption of the ORFs was carried out in the diploid strain FY1679 using the kanMX4 marker flanked by short sequences homologous to the target locus. Tetrad analysis following sporulation of the heterozygous disruptants showed that YBR254c and YBR257w are essential genes. YBR257w was later characterized and renamed POP4, its gene product being involved in 5.8S rRNA and tRNA processing (Chu et al., 1997). The tetrad analysis performed for the heterozygous disruptant for YBR2…

Molecular Characterization of a Chromosomal Rearrangement Involved in the Adaptive Evolution of Yeast Strains

2002

Wine yeast strains show a high level of chromosome length polymorphism. This polymorphism is mainly generated by illegitimate recombination mediated by Ty transposons or subtelomeric repeated sequences. We have found, however, that the SSU1-R allele, which confers sulfite resistance to yeast cells, is the product of a reciprocal translocation between chromosomes VIII and XVI due to unequal crossing-over mediated by microhomology between very short sequences on the 5' upstream regions of the SSU1 and ECM34 genes. We also show that this translocation is only present in wine yeast strains, suggesting that the use for millennia of sulfite as a preservative in wine production could have favored …