Comparison of Inhibitory Effects of Prolinal-Containing Peptide Derivatives on Prolyl Endopeptidases from Bovine Brain and Flavobacterium1

Abstract

The inhibitory effects of proline-containing peptides and their derivatives on prolyl endopeptidases from Flavobacterium meningosepticum and bovine brain were compared. Replacement of the carboxyl terminal proline in N-blocked peptides with prolinal resulted in remarkable decreases in Ki values for both prolyl endopeptidases. Further reduction of the prolinal to prolinol led to a decrease in their inhibitory effects. Z-Pro-, Z-Val-, and Suc-Pro-prolinals were similarly inhibitory for both the enzymes with Ki values of nM order. However, the inhibitory effects of Z-Pyr-prolinal and Boc-Pro-prolinal on these enzymes were significantly distinguished: they strongly inhibited the mammalian prolyl endopeptidase with Ki values of nM order, while the Ki values of these compounds for the microbial enzyme were only of microM order. These results suggest that there are some structural differences in the S2 and S3 subsites between the two enzymes, though their substrate specificities are apparently indistinguishable.

Active‐Site‐Directed Inhibitors of Prolyl Oligopeptidase Abolish Its Conformational Dynamics

“…Figure 3 A shows that highest amplitude motions were localized in the α/β-hydrolase domain. Afterwards, the effects of binding of the covalent active sitedirected inhibitors benzyloxycarbonyl-prolyl-prolinal (ZPP, Figure 1 C) [19] and KYP-2047 on POP conformational dynamics were examined. Extensive changes in the methyl-TROSY spectra of inhibited POP indicated large-scale conformational rearrangements upon inhibitor binding, which predominantly affected the α/β-hydrolase (Figures 3 B and S3).…”

Low molecular weight inhibitors of Prolyl Oligopeptidase: a review of compounds patented from 2003 to 2010

“…Peptidomimetic inhibitors are designed by systematic modification of the reference compound benzyloxycarbonylprolyl-prolinal (ZPP) (1, Table 2) [58]. This molecule acts as a transition state analogue, as shown by NMR [59] and X-ray [1] studies, and it was taken as a starting point in the ligand-based drug design for subsequent peptidomimetic inhibitors.…”

“…Proline, proline derivatives [58,60,[65][66][67][68][69] or natural a-amino acids, both neutral and charged, are fitted [70][71][72]. Moreover, a wide variety of cyclic or bicyclic scaffolds are compatible [73][74][75] while open chains can also be fitted.…”

“…ZPP (1, Table 2), a compound with potent inhibitory effect on mammalian POP, was discovered early on [58]. The aldehyde functionality was found to be required for correct binding.…”

Structure Activity Relationship of Inhibitors Specific for Prolyl Endopeptidase

“…3-Phenylpropiony/~Pro-pyrrolidine(15), 4-phenylbutyrylPro-pyrrolidine (17), 4-phenylbutyryl-Thiopro-thiazolidine (18), (i-naphthyl) acetyl-Pro-pyrrolidine (19) and (inaphthyl) acetyl-Thiopro-thiazolidine (20). These compounds were prepared from the respective N-blocked amino acids and the corresponding amines using DCC.…”