EVALUATION OF THE USE OF PHASE-SPECIFIC GENE PROMOTERS FOR THE EXPRESSION OF ENOLOGICAL ENZYMES IN AN INDUSTRIAL WINE YEAST-STRAIN

Genes as POT1, HSP104 and SSA3, which are late expressed in laboratory culture conditions are expressed only during the first few days in mi crovinifications in wine yeast cells. This effect is probably due to t he different growth conditions and leads to useless levels of enzyme a ctivity for a reporter gene. However the ACT1 promoter, which is const itutively expressed in laboratory conditions, produces sufficient amou nts of enzyme activity in late fermentation phases.