Reference

Inhibition of proteolytic activity of calcium activated neutral protease by leupeptin and antipain

Toyooka, Teruhiko; Shimizu, Teruo; Masaki, Tomoh (Res. Sect. Muscle Contraction, Tokyo Metrop. Inst. Med. Sci., Tokyo, Japan). Biochem. Biophys. Res. Commun., 82(2), 484-91 (English) 1978. CODEN: BBRCA9. ISSN: 0006-291X. DOCUMENT TYPE: Journal CA Section: 7 (Enzymes) The Ca2+-activated protease from bovine ventricular muscle requires mM concns. of Ca2+ for the activation of the proteolysis of troponin-T, troponin-I, and tropomyosin. Both leupeptin and antipain were effective for inhibition at nearly the same molar concn. as the protease. Lineweaver-Burk plots for both the protease alone and protease with leupeptin showed straight lines, and the mode of inhibition was noncompetitive. Natural actomyosin pretreated with this protease showed markedly reduced sensitivity to Ca2+. With the addn. of leupeptin to the pretreatment, however, the Ca2+ sensitivity was well preserved.In this study，54577-99-0 is also used. .