Application

Cathepsin B from bovine spleen has been used in cleavage assay before high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis. It has also been used in the enzyme inhibition assays with protease inhibitors RfIP1 and ruthenium metalloarenes.

Biochem/physiol Actions

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.

Cathepsin B displays an endopeptidase and peptidyl dipeptidase activities. It may be associated with the pathophysiology of tumors. Cathepsin B is also regarded as a prominent protease in Leishmaniasis. It is overactivated in muscular dystrophy, pulmonary emphysema, and bone resorption.

General description

Cathepsin B is a lysosomal enzyme that comprises a light chain (Lys1–Arg49) and a heavy chain (Val50–Thr253). It belongs to cysteine family C1.

Packaging

10, 25, 100 units in serum bottle

Physical form

Lyophilized powder containing sodium phosphate, sodium chloride and ~6% EDTA as stabilizer.

Unit Definition

One unit will hydrolyze 1 µmole of Z-lysine p-nitrophenyl ester per min at pH 5.0 at 25 °C.