Hybridization and spore dissection of native wine yeasts for improvement of ethanol resistance and osmotolerance.

Global warming has a significant impact on different viticultural parameters, including grape maturation. An increment of photosynthetic activity generates a rapid accumulation of sugars in the berry, followed by a dehydration process which leads to a higher concentration of soluble solids. This effect is exacerbated by current viticultural practices which favor the harvest of very mature grapes to obtain wines with sweet tannins.

Mutagenesis, screening and isolation of Brettanomyces bruxellensis mutants with reduced 4-ethylphenol production.

The use of non-conventional yeast species to obtain interesting flavors and aromas has become a new trend in the fermented beverages industry. Among such species, Brettanomyces bruxellensis (B. bruxellensis) has been reported as capable of producing desirable or at least singular aromas in fermented beverages like beer and wine.

Construction of low-ethanol-wine yeasts through partial deletion of the Saccharomyces cerevisiae PDC2 gene.

We propose an alternative GMO based strategy to obtain Saccharomyces cerevisiae mutant strains with a slight reduction in their ability to produce ethanol, but with a moderate impact on the yeast metabolism. Through homologous recombination, two truncated Pdc2p proteins Pdc2pΔ344 and Pdc2pΔ519 were obtained and transformed into haploid and diploid lab yeast strains. In the pdc2Δ344 mutants the DNA-binding and transactivation site of the protein remain intact, whereas in pdc2Δ519 only the DNA-binding site is conserved.