Synonym: Acetyl-Leu-Leu-Arg-al, N-Acetyl-L-leucyl-L-leucyl-L-argininal hemisulfate salt
CAS Number: 103476-89-7
Linear Formula: C20H38N6O4 · 1/2H2SO4
Molecular Weight: 475.59
MDL Number: MFCD00037012
PubChem Substance ID: 24896328
Analysis Note
Leupeptin gives multiple peaks on HPLC due to equilibria among three forms in solution. Purity determined using three main peaks. Majority of contaminating peptide is racemized leupeptin.
Biochem/physiol Actions
Inhibitor of serine and cysteine proteases. Inhibits plasmin, trypsin, papain, calpain, and cathepsin B. Does not inhibit pepsin, cathepsins A and D, thrombin, or a-chymotrypsin. Effective concentration 10-100 µM. There have been numerous studies using leupeptin to protect against hearing loss caused by acoustic overstimulation or the ototoxic antibiotic gentamicin. (Loss of cochlear hair cells is believed to be mediated by calpain.)
Quality Level: PREMIUM
Biological Source: microbial
Assay: =90% (HPLC)
Solubility: H2O: soluble10 mM (Solutions are stable for a week at 4 °C. Stock solutions are stable up to 6 months at -20 °C.); H2O: soluble50 mg/mL
Storage Temp.: -20°C