Leupeptin hemisulfate (103476-89-7) is a reversible inhibitor of trypsin-like proteases and cysteine proteases. Inhibits trypsin, plasmin, papain and cathepsin B, H and L.1-3 Blocks various apoptotic pathways in T cells.4 Commonly used in cell lysis buffers to protect proteins from degradation. Typical working concentration is 1µM (0.5 µg/ml).
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2) Barrett et al. (1981), Cathepsin B, Cathepsin H and Cathepsin L; Methods Enzymol., Pt C, 80 535
3) Knight et al. (1980), Human cathepsin B. Application of the substrate N-benzyloxycarbonyl-L-arginyl-L-arginine 2-naphthylamide to a study of the inhibition by leupeptin; Biochem. J., 189 447
4) Sarin et al. (1995), A protease-dependent TCR-induced death pathway in mature lymphocytes; J. Immunol., 154 5806