Proteinase K (from Tritirachium album ) is a non-specific protease of the serine protease family. Proteinase K is used for the cleavage of proteins in nucleic acid preparations. It is mainly used in nucleic acid purification or for the removal of nucleases. Proteinase K is active under a wide range of reaction conditions, including elevated temperatures and presence of SDS. Directions for use Foreign activity: RNAse and DNAse not detectable Optimum temperature: +65 °C. Activity at +65 °C is ca. 12 x higher than at +25 °C. Over +65 °C, inactivation due to denaturation. Activators: Denaturating agents like SDS (0,5-1 %), urea. Inhibitors: Inhibition with Hg 2+ -ions, DFP, PMSF and phenol. Not inhibited by EDTA, sulfhydryl reagents and trypsin or chymotryps ininhibitors. Stability: pH 4.0-12.5. pH optimum: 8,0. Also stable even when denaturing agents, e.g. SDS and urea are present. Stabilisers: Ca 2+ -ions (1-5 mM) prevent autolysis. Proteinase K ≥30 mAnson U/mg, BioAnalysis Grade, lyophilized A non-specific endopeptidase with strong proteolytic activity for degrading proteins in biological samples. A quality product for molecular biology with a broad scope of application. Directions for use Working solution: 50 µg/ml Reaction buffer: 50 mM Tris-HCl; pH 7.5; 5 mM CaCl 2 ; 0.5 % SDS