MIXED LACTIC-ACID ALCOHOLIC FERMENTATION BY SACCHAROMYES CEREVISIAE EXPRESSING THE LACTOBACILLUS-CASEI L(-LDH())

We describe the construction of a Saccharomyces cerevisiae strain expr essing the gene encoding the L(+)-lactate dehydrogenase [L(+)-LDH)] fr om Lactobacillus casei. The recombinant strain is able to perform a mi xed lactic acid-alcoholic fermenation. Yeast cells expressing the L(+) -LDH gene from the yeast alcohol dehydrogenase (ADH1) promoter on a mu lticopy plasmid simultaneously convert glucose to both ethanol and lac tate, with up to 20% of the glucose transformed into L(+)-lactate. Suc h strains mag be used in every field where both biological acidificati on and alcoholic fermentation are required.