Sigma-Aldrich Quality Level 200 assay ≥95% (gel filtration chromatography) form crystalline solid

A competitive and reversible inhibitor of esterase and protease activity. Forms a tight complex with and blocks the active site of target enzymes. Inhibits a number of different proteases, including chymotrypsin, coagulation factors involved in the pre-phase of blood clotting, kallikrein (K_d = 1 X 10^-7 M), plasmin (K_d = 2.3 X 10^-10 M), tissue and leukocyte proteinases, and trypsin (K_d = 5 X 10^-14 M). Does not inhibit Factor Xa or thrombin. Reported to be relatively acid and heat stable. Effectively inhibits target proteases at equimolar concentration. Useful as a serine proteinase inhibitor during purification of proteins and in studies of zymogen activation systems. Reported to suppress virus HA cleavage and limit reproduction of human and avian influenza viruses with a single arginine in the HA cleavage site.

A competitive and reversible inhibitor of esterases and proteases. Forms a tight complex with and blocks the active site of the enzymes. Inhibits a number of different proteases, including chymotrypsin, coagulation factors involved in the prephase of blood clotting, kallikrein (K_d = 1 x 10^-7 M), plasmin (K_d = 2.3 x 10^-10 M), tissue and leukocytic proteinases, and trypsin (K_d = 5 x 10^-14 M). Does not inhibit Factor Xa and thrombin. It is relatively acid- and heat-stable. Useful as a serine protease inhibitor during purification of proteins and in studies of zymogen activation systems. Reported to suppress virus HA cleavage and limit reproduction of human and avian influenza viruses with a single arginine in the HA cleavage site.

Effectively inhibits target proteases at equimolar concentration.

Note: 1 KIU = 0.025 antiplasmin units (APU) = 0.0016 trypsin inhibitor units (using porcine trypsin) = 0.0009756 trypsin inhibitor units (using bovine trypsin).

Kd = 1 x 10-7 M, 2.3 x 10-10 M, 5 x 10-14 M, against kallikrein, plasmin, and trypsin, respectively

Primary Target
chymotrypsin

Toxicity: Standard Handling (A)

One Kallikrein Inhibitory Unit (K.I.U.) is defined as the quantity of protease inhibitor that will inhibit two kallikrein units by 50% under optimal conditions. Note: 1 KIU = 0.025 antiplasmin units (APU) or 0.0031 trypsin inhibitor units.

Following reconstitution refrigerate (4°C). Stock solutions are stable for up to 3 months at 4°C.

Zhirnov, O.P., et al. 2011. Antiviral Res.92, 27.
Roberts, R.F., et al. 1998. Ann. Thorac. Surg.66, 225.
Azougagh Oualane, F., et al. 1992. Thromb. Res.68, 185.
Anderson, L.O., et al. 1986. Proc. Natl. Acad. Sci. USA83, 2979.
Kruithof, W.L., et al. 1986. Biochem. J.226, 631.
McKeehan, W.L., et al. 1986. J. Biol. Chem.261, 5378.
Fritz, H., and Wunderer, G. 1983. Arzneim. Forsch.33, 479.
Rijken, D.C., and Collen, D. 1981. J. Biol. Chem.256, 7035.
Kassell, B., et al. 1970. Methods Enzymol.19, 845.

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