Patent ID: 7820801
Filing Date: 2010-10-26
Classification: C11D,C12N

Abstract:
1. A method for producing solid proteinase K which is insoluble in water, the method comprising tile steps of: adding to an aqueous solution of proteinase K ammonium sulfate in an amount of 0.1 to 0.2 M per 5 minutes up to a final amount of 1.5 to 2 M after 1 hour, thereby precipitating the proteinase K as a solid, resuspending the solid proteinase K in a buffer comprising Tris and calcium acetate, isolating the solid proteinase K, washing the solid proteinase K with an aqueous buffer or water to yield solid proteinase K and a supernatant, and measuring proteinase K activity in the supernatant, wherein the washing step is repeated until no proteinase K activity is measurably detected in the supernatant.