Table 3.
Effects of heptapeptides (PACEI) on prolyl endopeptidase (PEP) activity.
| Peptide (1 mg/mL) | Sequence 1 | PEP Residual Activity (%) 2 |
|---|---|---|
| PACEI48L | Ac-RKWFHLW-NH2 | 61.4 ± 4.4 ** (a) |
| PACEI49L | Ac-RKWFLHW-NH2 | 46.8 ± 9.1 ** (b) |
| PACEI50L | Ac-RKWHFLW-NH2 | 6.4 ± 2.3 ** (c) |
| PACEI51L | Ac-RKWHLFW-NH2 | 71.6 ± 4.9 ** (a) |
| PACEI52L | Ac-RKWLFHW-NH2 | 65.9 ± 3.6 ** (a) |
| PACEI53L | Ac-RKWLHFW-NH2 | 71.5 ± 4.5 ** (a) |
1 All the peptides were acetylated at the N-terminus (Ac) and amidated at the C-terminus (NH2). 2 Data are expressed as the percentage of PEP residual activity with respect to a control without peptide (100%) and are the mean ± SD of three replicates. ** Significant inhibition with respect to control (p < 0.01) (Student’s t-test on absolute values of PEP activity). Data with the same letter do not differ at the 95% level of confidence (Tukey’s honestly significant difference (HSD) procedure).