CHEMBL5738706

PREP Enzymatic Activity Assay: PREP enzymatic activity assay. To assay baseline prolyl endopeptidase (PREP) activity, 20 ng of recombinant human PREP (rhPREP) (R&S system, #4308-SE) or 20 ng of recombinant mouse PREP (rmPREP) (R&S system, #6339-SE) was incubated with 100 μM of Z-Gly-Pro-AMC peptide (BACHEM, #L-1145) in a PREP assay buffer (25 mM Tris, 250 mM NaCl, 10 mM DTT, pH 7.5) for 30 min at 37° C. protected from light in 96-well black plates (Nunc, #237108). To assay PREP activity inhibition by test compounds, test compounds were pre-incubated with the enzyme for 15 min at 37° C. before starting the reaction by substrate addition in 96-well black plates (Nunc, #237108). 7-Amino-4-Methylcoumarin (AMC) release was detected by measuring fluorescence at Ex/Em 380/460 nm using a Multifunction Microplate Reader (Synergy 4, Biotek). All measurements were carried out in triplicate. Val-boroPro, a non-specific prolyl peptidase inhibitor, was used as a positive control.