Liquid. In 35 mM potassium phosphate, 35 mM Sodium acetate, 2 mM DTT, 2 mM EDTA, 50% ethylene glycol, pH 6.5. AVOID FREEZE/THAW CYCLES. Recombinant, human cathepsin S expressed in E. coli without a tag or fusion protein. A major lysosomal cysteine proteinase preferentially expressed in macrophages and microglia. Exhibits high specific activity. Specific activity: ≥30,000 mU/mg protein. One unit is defined as the amount of enzyme that will hydrolyze 1.0 µmol Z-VVR-AMC per min at 37°C, pH 6.5. Note: 1 mU = 1 milliunit. Purity: ≥90% by SDS-PAGE. EC 3.4.22.27. Note: 1 mU = 1 milliunit.

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