Lyophilized. Lyophilized from 2 mM sodium phosphate buffer, pH 6.5. Native cathepsin D from bovine spleen. Cathepsin D is a major lysosomal aspartyl proteinase widely distributed in many cell types. It exists in two forms, a single polypeptide chain of 46 kDa, and a two-polypeptide chain form consisting of an H-chain of 34 kDa and an L-chain of 12 kDa. Specific activity: ≥400 units/mg protein. One unit is defined as the amount of enzyme that will digest acid-denatured hemoglobin in 30 minutes, at 37°C, pH 3.3, releasing peptides soluble in TCA, as measured by an increase in absorbance of 0.5 at 280 nm. Purity: ≥98% by SDS-PAGE. EC 3.4.23.5, CAS 9025-26-7.

Ref.: Berchem, G., et al. 2002. Oncogene 21, 5951. Fortgens, P.H., et al. 1997. Immunopharmacology 36, 305. Takahashi, T., and Tang, J. 1981. Methods Enzymol. 80 (Pt. C), 565.