Proteinase K from Tritirachium album is a subtilisin-related serine protease. It is an endopeptidase with a very high specific activity and a broad spectrum of action. The enzyme is a 28.9 kDa protein expressed in Pichia Pastoris. It is widely used for digestion of proteins, including DNases and RNases during nucleic acid preparations without compromising the integrity of the isolated DNA or RNA. It is active in a wide range of reaction conditions.