CHEMBL5736403

Enzyme Inhibition Assay: Assay buffer (50 mM Tris-HCl, 140 mM NaCl, 5 mM KCl, 1 mM CaCl2, 1 mM MgCl2, 0.01% Triton-X-100, pH 8.0;ATX solution: ATX (human His-tagged) stock solution (1.08 mg/mL in 20 mM bicine, pH 8.5, 0.15 M NaCl, 10% glycerol, 0.3% CHAPS, 0.02% NaN3), diluted to 1.4-2.5× final concentration in assay buffer;MR121 substrate solution: MR121 substrate stock solution (800 μM MR121 substrate in DMSO), diluted to 2-5× final concentration in assay buffer.Test compounds (10 mM stock in DMSO, 8 μL) were obtained in 384 well sample plates (Corning Costar #3655) and diluted with 8 μL DMSO. Row-wise serial dilutions were made by transferring 8 μL cpd solution to the next row up to row O. The compound and control solutions were mixed five times and 2 μL were transferred to 384 well assay plates (Corning Costar #3702). Then, 15 μL of 41.7 nM ATX solution was added (30 nM final concentration), mixed five times and then incubated for 15 minutes at 30° C. 10 μL of MR121 substrate solution was added (1 μM final concentration), mixed 30 times and then incubated for 15 minutes at 30° C.Fluorescence was then measured every 2 minutes for 1 hour (Perkin Elmer plate: vision multimode reader); light intensity: 2.5%; exp. time: 1.4 sec, Filter: Fluo_630/690 nm) and IC50 values were calculated from these readouts.