Leupeptin Hemisulfate (Microbial)

Leupeptin is a reversible competitive inhibitor of serine and thiol proteases that, competes with substrate for the active site of the enzyme. It has been reported to, inhibit calpain, cathepsin B and trypsin, for example. Leupeptin is often used for the inhibition of plasmin, trypsin, papain, kallikrein and cathepsin B. No inhibition found with pepsin, cathepsins A and D, elastase, renin or chymotrypsin. A typical working concentration is in the range of 10-100uM, Leupeptin has 3 tautomeric isomers which are separated by chromatography. Synonyms: Microbial Leupeptin, Acetyl-Leu-Leu-Arg-al, Leupeptin hemisulfate salt, N-Acetyl-L-leucyl-L-leucyl-L-argininal hemisulfate salt , CAS Number:, 103476-89-7, Molecular Formula: C20H38N6O41/2H2SO4, Molecular Weight (Sulfate Form) (Ac-Leu-Leu-Argininal): 426.55, Appearance: White powder, Optical Rotation: -80.0° ± 2°, Water: <5%, Specific Activity (Trypsin/TAME): ~1.2ug/ml, Solubility: Soluble in water, ethanol, acetic acid and DMF. Clear to v.slightly hazy solution at 50mg/mL in water. Storage and Stability: Lyophilized powder may be stored at -20°C. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Product is stable for 6 months after receipt at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.