Description_x000D_ General description_x000D_ Cathepsin B is encoded by the gene CTSB and is located in the human chromosome at 8p23.1. Cathepsin B is a lysosomal proteolytic enzyme of cysteine protease family. It is present in all mammalian cells. It is essential for the intracellular protein turnover._x000D_ Application_x000D_ Cathepsin B from human placenta has been used in the in vitro digestion of modified myelin oligodendrocyte glycoprotein (MOG). It has also been used in determining the effect of cysteine protease inhibitors._x000D_ Cathepsin B is a lysosomal cysteine proteinase which hydrolyzes proteins with a broad specificity for peptide bonds. Cathepsin B may be a useful tool in Alzheimer’s research, as it may have a role in the natural defense against the disease . Cathepsin B may be used to cleave procaspase 1 and procaspase 11, and to induce apoptosis in digitonin-permeabilized cells._x000D_ Packaging_x000D_ 2, 10 units in serum bottle_x000D_ Biochem/physiol Actions_x000D_ Cathepsin B preferentially cleaves at the caboxyl side of Arg-Arg bonds in small molecule substrates. Cathepsin B has been shown to degrade β-amyloid precursor protein into harmless fragments . Cathepsin B inhibition has been shown to limit bone metastasis in breast cancer ._x000D_ Cathepsin B has been found to cleave procaspase 1 and procaspase 11 and to induce apoptosis in digitonin-permeabilized cells. Translocation of cathepsin B from the cytoplasm to the nucleus contributes to bile salt induced apoptosis of rat hepatocytes. Levels of cathepsin B in PC12 cells significantly decrease 12 to 24 hours after apoptosis is induced._x000D_ Unit Definition_x000D_ One unit will liberate 1 nanomole of 7-amino-4-methylcoumarin from Z-Arg-Arg 7-amido-4-methylcoumarin per min at pH 6.0 at 40 °C._x000D_ Physical form_x000D_ Lyophilized powder containing phosphate buffer salts_x000D_ Preparation Note_x000D_ Dissolves in water at 1 mg/mL concentration, yieliding a clear solution.