Liquid. In 50 mM sodium acetate buffer, 1 mM EDTA, pH 5.0. AVOID FREEZE/THAW CYCLES. Native cathepsin B from human liver, purified by affinity chromatography. The most investigated enzyme of all lysosomal cysteine proteases. Upregulation and secretion of cathepsin B have been shown to occur in many types of tumors and to correlate positively with their invasive and metastatic capabilities. Cathepsin B is shown to facilitate tumor invasion by dissolving extracellular barriers. Specific activity: ≥50 U/mg protein. One unit is defined as the amount of enzyme that will hydrolyze 1.0 µmol Z-RR-bNA per min at 40°C, pH 6.0 in the presence of DTT. Purity: >95% by SDS-PAGE. Prepared from tissue of individuals that have been shown by certified tests to be negative for HBsAg and for antibodies to HIV and HCV. pH optimum 3.5 - 6.0. EC 3.4.22.1, CAS 9047-22-7.

Merck Index: 14, 1905
Ref.: Kostoulas, G., et al. 1999. FEBS Lett. 455, 286. Berquim, I.M., and Sloane, B.F. 1996. Adv. Exp. Med. Biol. 389, 281. Keppler, D., et al. 1994. Biochim. Biophys. Acta. 1226, 117. Musil, D., et al. 1991. EMBO J. 10, 2321. Sloane B.F. 1990. Semin. Cancer Biol. 1, 137.