PMID: 16970398 , Related PDB ids: 2C1E, 2C2K, 2C2M, 2C2O, 2C2Z

Authors:

Ekici OD, Li ZZ, Campbell AJ, James KE, Asgian JL, Mikolajczyk J, Salvesen GS, Ganesan R, Jelakovic S, Grutter MG, Powers JC

Title:

Design, synthesis, and evaluation of aza-peptide Michael acceptors as selective and potent inhibitors of caspases-2, -3, -6, -7, -8, -9, and -10.

Journal:

J Med Chem. 2006 Sep 21;49(19):5728-49.

Abstract:

Aza-peptide Michael acceptors are a novel class of inhibitors that are potent and specific for caspases-2, -3, -6, -7, -8, -9, and -10. The second-order rate constants are in the order of 10(6) M(-1) s(-1). The aza-peptide Michael acceptor inhibitor 18t (Cbz-Asp-Glu-Val-AAsp-trans-CH=CH-CON(CH(2)-1-Naphth)(2) is the most potent compound and it inhibits caspase-3 with a k(2) value of 5620000 M(-1) s(-1). The inhibitor 18t is 13700, 190, 6.4, 594, 37500, and 173-fold more selective for caspase-3 over caspases-2, -6, -7, -8, -9, and -10, respectively. Aza-peptide Michael acceptors designed with caspase specific sequences are selective and do not show any cross reactivity with clan CA cysteine proteases such as papain, cathepsin B, and calpains. High-resolution crystal structures of caspase-3 and caspase-8 in complex with aza-peptide Michael acceptor inhibitors demonstrate the nucleophilic attack on C2 and provide insight into the selectivity and potency of the inhibitors with respect to the P1' moiety.