YEAST CELL WALL DISSOLVING ENZYME AND EXTRACTION OF YEAST CELL COMPONENT USING SAID ENZYME

摘要

PURPOSE:To efficiently produce a yeast cell dissolving enzyme having specific properties, by cultivating a strain belonging to the genus Rhizopus, separating a culture solution by centrifugation, freeze-drying the extracted solution and drying. CONSTITUTION:A strain belonging to the genus Rhizopus such as Rhizopus delemar JCM5565 is inoculated into a wheat bran which is sprinkled with water and denatured under heating by a conventional procedure and cultivated at about 20-40 deg.C culture temperature for about 2-8 days. The culture mixture is suspended in water, centrifuged and the supernatant liquid is directly freeze- dried in vacuum to give a yeast cell dissolving enzyme. The enzyme has the following properties. Disc electrophoresis: single peak. Molecular weight: 4,200+ or -400. Isoelectric point: pI7.7+ or -0.2. Stable pH: 3-8. Optimum action pH: 5. Optimum action temperature: 50 deg.C. Stability: having about 70% remaining activity treatment at 60 deg.C for 30min.