A potent, cell-permeable, and reversible proteasome inhibitor. Inhibits the chymotrypsin-like activity of the pituitary multicatalytic proteinase complex (MPC; K_i = 460 nM). Does not inhibit the peptidyl-glutamyl peptide hydrolyzing activity of MPC even at concentrations of 200 µM. Also blocks the decay of IκB-α and IκB-β proteins in exponentially growing WEHI 231 cells.

Cell permeable: yes

Primary Target
MPC

Product does not compete with ATP.

Reversible: yes

Target K_i: 460 nM against the pituitary multicatalytic proteinase complex (MPC)

Toxicity: Standard Handling (A)

Z-Leu-Leu-Phe-CHO

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months.

Schauer, S.L., et al. 1998. J. Immunol. 160, 4398.
Orlowski, M., et al. 1997. Biochemistry 36, 13946.
Orlowski, M., et al. 1993. Biochemistry 32, 1563.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany