CONSTRUCTION OF FLOCCULANT BREWERS-YEAST BY CHROMOSOMAL INTEGRATION OF THE YEAST FLOCCULATION GENE FLO1

Yeast flocculation gene FLO1, located on chromosome I of Saccharomyces cerevisiae, has been cloned previously16. However, it has recently be en found that the gene was an in-frame deletion derivative of the chro mosomal intact FLO1 gene19. When introduced into non-flocculent indust rial strains, including brewer's yeast, the latter gene, FLO1L, contai ning an open reading frame of 4,611 bp, conferred stronger flocculatio n than the former gene, FLO1S, containing an open reading frame of 2,5 86. By chromosomal integration of the ADH1-controlled FLO1L gene, ''ge ne therapy'' of the flocculation behaviour of the parent non-flocculen t brewer's yeast was successfully achieved.