Small peptide inhibitors of acetyl-peptide hydrolase having an uncommon mechanism of inhibition and a stable bent conformation.
Acyl peptide hydrolase (APEH) catalyzes the removal of acetyl-amino acids from the N-terminus of peptides and cytoplasmic proteins. Due to the role played in several diseases, and to the growing interest around N-terminal acetylation, studies on APEH structure, function, and inhibition are attracting an ever increasing attention. We have therefore screened a random tetrapeptide library, N-capped with selected groups, and identified a trifluoroacetylated tetrapeptide (CF(3)-lmph) which inhibits the enzyme with a K(i) of 24.0 ± 0.8 μM. The inhibitor is selective for APEH, shows an uncommon uncompetitive mechanism of inhibition, and in solution adopts a stable bent conformation. CF(3)-lmph efficiently crosses cell membranes, blocking the cytoplasmic activity of APEH; however, it triggers a mild pro-apoptotic effect as compared to other competitive and noncompetitive inhibitors. The unusual inhibition mechanism and the stable structure make the new compound a novel tool to investigate enzyme functions and a useful scaffold to develop more potent inhibitors.
Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, 80134, Napoli, Italy.
A
A
Sandomenico
A
A
Russo
G
G
Palmieri
P
P
Bergamo
M
M
Gogliettino
L
L
Falcigno
M
M
Ruvo
D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D002463:Cell Membrane Permeability; D002942:Circular Dichroism; D006801:Humans; D056004:Molecular Dynamics Simulation; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D010447:Peptide Hydrolases / Q000737:chemistry*; D019151:Peptide Library; D011480:Protease Inhibitors / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D011487:Protein Conformation; D013329:Structure-Activity Relationship
D009842:Oligopeptides; D019151:Peptide Library; D011480:Protease Inhibitors; D010447:Peptide Hydrolases; C038220:acylaminoacyl-peptidase