Description General description Cathepsin K is a member of the papain superfamily of cysteine proteinases and plays an important role in osteoclast-mediated bone resorption and collagen degradation. It is primarily expressed by osteoclasts and recent studies also suggest its expression in fibroblasts. Irregularities in cathepsin K activity, either too high or too low, contribute to osteopenic disorders such as osteoporosis and pycnodysostosis. This recombinant enzyme contains a C-terminal His•Tag sequence. Cathepsin K is a member of the papain superfamily of cysteine proteinases and plays an important role in osteoclast-mediated bone resorption and collagen degradation. It is primarily expressed by osteoclasts. Recently reported to also be expressed in fibroblasts. Irregularities in activity contribute to osteopenic disorders such as osteoporosis and pycnodysostosis. Contains a C-terminal His•Tag. Note: 1 mU = 1 milliunit. Packaging 25 μg in Plastic ampoule Please refer to vial label for lot-specific concentration. Warning Toxicity: Standard Handling (A) Unit Definition One unit is defined as the amount of enzyme that will hydrolyze 0.4 µmol Z-FR-AMC per min at 37°C, pH 5.5. Physical form In 50 mM NaOAC, pH 5.5. The activation was stopped by addition of 10 mM MMTS, which can be removed under reducing conditions. Reconstitution Following initial thaw, aliquot and freeze (-70°C). Other Notes Delaisse, J.M., et al. 2003. Microsc. Res. Tech.61, 504. Dodds, R.A. 2003. Cell Biochem. Funct.21, 231. Everts, V., et al. 2003. Calcif. Tissue Int.73, 380. Hou, W.S., et al. 2003. Biol. Chem.384, 891.