Evaluation of the expression of the FLO genes in two industrial brewing yeast strains .

Yeast flocculation is a natural event that led to get clear and stable products in brewing and another fermented products. However, when it is unsuccessful is necessary to employ filtration processes. The flocculin proteins, coded for family FLO genes, are responsible for the flocculation. In this study, we analyzed the transcriptome of two Saccharomyces pastorianus yeast strains. To get information about isoforms, molecular size and expression (in fpkm) of flocculins, we analyzed the genetic expression of FLO1, FLO5, FLO8, FLO9, FLO10 and FLO11 genes. Fermentations performed under standard conditions for lager beer kind and after two, and five fermentation days, samples taken and RNA purified. Our results showed differences at molecular size than previously reported. These ones could be responsible for the flocculation capacity of the strains. The structural analysis of the flocculins allows locating the difference in the domain between the brewing strains and the reference strains. [ABSTRACT FROM AUTHOR]