| Abstract | dc.description.abstract | The yeast Saccharomyces cerevisiae is the
main microorganism responsible for wine fermentation and
its development influences the quality of wine. A problem
affecting these types of fermentations, generating important
losses in this industry, are the slow or stuck fermentations
which may result from low nitrogen availability in
the must. Therefore, several studies have been directed
towards identifying genes involved in nitrogen metabolism
using high throughput strategies which include subjecting
the yeast to changes in the type or concentration of the
available nitrogen source. However, this type of approach
can also generate responses in the yeast that do not necessarily
alter the expression of genes related to nitrogen
metabolism. In this work, by using intraspecific hybridisation
of wild wine yeast strains we obtained genetically
and oenologically similar strains with differences in the
consumption of nitrogen sources. Using the same must, the
global expression patterns of these yeasts were compared
by microarrays, the analysis of which identified 276 genes
that varied in their expression between the strains analysed.
The functional analysis of the genes with a known function
indicates that some participate in nitrogen metabolism,
alcoholic fermentation, ion transport and transcriptional
regulation. Furthermore, differences were observed in the
expression of genes which have been partially associated to
nitrogen, as in the case of ZRT1 and ATO2. Interestingly,
many of the genes identified have no known function or
have not been previously associated to this phenotype. | es_CL |
