Biochem/physiol Actions Chymostatin is a strong inhibitor of many proteases, including chymotrypsin, papain, chymotrypsin-like serine proteinases, chymases, and lysosomal cysteine proteinases such as cathepsins A,B,C, B, H, and L. It weakly inhibits human leucocyte elastase. It is effective at a final concentration of 100 to 200 μg/ml (10 to 100 μM). Chymostatin is often included in protease inhibitor cocktails used with plant extracts.
Other Notes A mixture of A (major), B and C components. A: X=Leu; B: X=Val; C: X=Ile
chymostatin A MW = 607.7
chymostatin B MW = 593.7
chymostatin C MW = 607.7
Preparation Note Solubility testing in glacial acetic acid at 10 mg/ml yields a clear solution, which is usually colorless, but can be yellow in appearance. It is reportedly also soluble in DMSO; only slightly soluble in water and short-chain alcohols; insoluble in ethyl acetate, butyl acetate, ether, hexane, and petroleum ether. Stock solutions (10 mM) can be prepared in DMSO and are stable for months at -20 °C. Stock solutions can also be made in 0.1 M HCl. Dilute solutions (10-100 μM) are only stable for several hours, due to oxidation of the terminal aldehyde.