| abstract |
A YEAST WHICH HARBORS A MUTANT GLUTATHIONE SYNTHETASE HAVING ONE OR BOTH OF MUTATIONS SELECTED FROM THE GROUP CONSISTING OF A MUTATION TO REPLACE A THEREONINE RESIDUE AT THE POSITION 47 WITH AN ISOLEUCINE RESIDUE AND A MUTATION TO REPLACE A GLYCINE RESIDUE AT THE 387-POSITION WITH AN ASPARTIC ACID RESIDUE AND PRODUCES Y-GLUTAMYLCYSTEINE. THE YEAST IS CULTURED UNDER SUITABLE CONDITIONS, THE RESULTANT CULTURE OR FRACTIONATION PRODUCT THEREOF OR THE RESULTANT CULTURE OR FRACTIONATION PRODUCT THEREOF THAT HAD BEEN HEAT-TREATED IS MIXED WITH FOOD OR BEVERAGE MATERIALS AND PROCESS INTO FOODS OR BEVERAGE TO PRODUCE Y-GLUTAMYLCYSTEINE- OR CYSTEINE-CONTAINING FOODS OR BEVERAGE. |