193,00  excl. 19% VAT


4381-v 0.2 mg | 193.00 EUR

(2R)- 2- [Acetyl- (N- Methyl- L- Isoleucyl)- L- Isoleucyl- L- Threonyl- L- Leucyl]- 2- Methyloxirane

(M.W. 554.72) C28H50N4O7

Synthetic Product

Inhibitor for Proteasome

Potent and Selective Proteasome Inhibitor

Epoxomicin was originally isolated from the culture medium of an Actinomycetes strain based on its in vivo antitumor activity against murine B16 melanoma [J. Antibiot., 45, 1746 (1992)].

In 1999, L. Meng et al. reported that the potent inhibitory activity of epoxomicin specifically targets the proteasome. In contrast to peptide aldehyde proteasome inhibitors, epoxomicin does not inhibit nonproteasomal proteases such as calpain, papain, chymotrypsin, trypsin, and cathepsin B at concentrations of up to 50 µM [Proc. Natl. Acad. Sci. USA, 96, 10403 (1999)]. This specific activity of epoxomicin may be explained by the proposed inhibition mechanism based on the X-ray analysis data reported by M. Groll et al. [J. Am. Chem. Soc., 122, 1237 (2000)]. In addition, L. Meng et al. also reported that epoxomicin shows almost equal activity with Z-Leu-Leu-Leu-H [MG-132] in accumulation of p53 and ubiquitinated proteins in cultured cell, and its potency is much stronger than that of lactacystin. This fact implies that Epoxomicin is a cell-permeable strong inhibitor for proteasome.

The offered Epoxomicin is a chemically synthesized product manufactured by Peptide Institute, Inc. In the preliminary experiments in the laboratory from Peptide Institute, our epoxomicin showed approx. IC50 value of 9 nM against commercially available 20S proteasome. This IC50 value is similar to that of Z-Leu-Leu-Leu-H (aldehyde) (MG132), and the potency is approx. 100 fold stronger than that of Lactacystin.

Chemically synthesized Epoxomicin manufactured from Peptide Institute, Inc., having characteristics of cell-permeable, irreversible, potent, and specific inhibitory activity for proteasome, is now available in Europe through Peptanova GmbH. We can offer prompt delivery ex stock Sandhausen within 1-3 working days. This inhibitor is not manufactured under GMP and is for research and laboratory use only.


  1. L. Meng, R. Mohan, B.H.B. Kwok, M. Elofsson, N. Sin and C.M. Crews, Proc. Natl. Acad. Sci. USA, 96, 10403 (1999) (Proteasome Inhibitor & Antiinflammatory Activity)
  2. N. Sin, K.B. Kim, M. Elofsson, L. Meng, H. Auth, B.H.B. Kwok and C.M. Crews, Bioorg. Med. Chem. Lett., 9, 2283 (1999) (Proteasome Inhibitor)
  3. K.B. Kim, J. Myung, N. Sin and C.M. Crews, Bioorg. Med. Chem. Lett., 9, 3335 (1999) (Proteasome Inhibitor)

Links to publications that use our inhibitor Epoxomicin | code 4381-v:

  1. Proteasome properties of hemocytes differ between the whiteleg shrimp Penaeus vannamei and the brown shrimp Crangon crangon (Crustacea, Decapoda)