Proteinase K is a stable serine protease with broad substrate specificity. It degrades many proteins in the native state even in the presence of detergents (1% Triton or 0.5% SDS). Proteinase K was isolated from a fungus (Engyodontium album, formerlyTritirachium album) able to grow on keratin and the enzyme can digest native keratin (hair), hence, the name "Proteinase K". NZYTech Proteinase K is a highly stable enzyme with an optimum temperature of 37 ºC (activity range 20-60 ºC) and optimum pH of 8.0 (activity range 7.5-9.0).