Liquid. In 500 mM NaCl, 25 mM Tris, pH 8.0. AVOID FREEZE/THAW CYCLES. Recombinant, human procathepsin K (amino acids 19-329) (GenBank target symbol = S79895, ACC No. P43235) expressed in E. coli with a methionine residue inserted at amino acid 18 to create a new N-terminal initiation site. Cathepsin K, a member of the papain superfamily of cysteine proteinases, plays an important role in osteoclast-mediated bone resorption and collagen degradation. Cathepsin K is synthesized as an inactive proenzyme that is converted to its mature, active form by proteolytic cleavage of the 99 amino acid propeptide domain. Inhibitors of cathepsin K include leupeptin (Cat. No. 108975) (IC50 = 70 nM), E-64 (Cat. No. 324890) (IC50 = 5 nM), and cystatin (Cat. No. 324891 or 324896). Requires activation prior to use. Activity: ≥1000 mU/mg protein. One unit is defined as the amount of enzyme that will hydrolyze 1 µmole benzyloxycarbonyl-phenylalanine-arginine-7-amido-4-methylcoumarin per min at 37°C, pH 5.5. Purity: ≥95% by SDS-PAGE. If the activated enzyme is not used immediately, it is recommended to add methyl methanthiosulfonate (1 mM final concentration MMTS). EC 3.4.22.38. Note: 1 mU = 1 milliunit. Ref.: McQueney, M., et al. 1997. J. Bio. Chem. 272, 13955. Bossard, M., et al. 1996. J. Biol. Chem. 271, 12517. Drake, F., et al. 1996. J. Biol. Chem. 271, 12511. Bromme, D. and Okamoto, K. 1995. Biol. Chem. Hoppe-Seyler 376, 379. Baron, R. 1989 Anat. Rec. 224, 317. Littlewood-Evans, A.J., et al. 1975. Cancer Res. 57, 5386. Nishimura, J.S. et al. 1975. Arch. Biochem. Biophys. 170, 461. |
