Inhibition of Caspase 4 (unknown origin) using Ac-LEHD-AMC substrate assessed as residual activity at 10 uM incubated for 15 mins prior to substrate addition measured for 2 hrs
Fluorometric Enzymatic Assay: The inhibition of the activity of Caspase-1 to -10 by four different compounds (#53, #111, #123 & Z-DEVD-FMK used as a prodrug: z-D(OMe)E(OMe)VD(OMe)FMK (comparison control compound, SM Biochemicals LLC, Cat# SMFMK003)) and their respective IC50 values were determined using a fluorometric enzymatic assay (Active Recombinant Caspase Set IV (BioVision, Cat# K233-10-25) and Caspase Fluorometric Substrate Set II Plus (BioVision, Cat# K137-9-25)) on a Flexstation 3x (Molecular Devices). In brief, each compound was serially diluted for a final test concentration range of 0.1 nM to 3.3 uM (10-point titration). Each active recombinant Caspase (Active Recombinant Caspase Set IV (BioVision, Cat# K233-10-25)) was added to the respective wells of the 96-well High Efficiency plates (Molecular Devices, Cat#75-000-0005), followed by the addition of the diluted test compounds. DMSO (Final=1%) or Z-VAD-FMK (Caspase-Family Inhibitor, Z-VAD-FMK (BioVision, Cat#1010-100).
Inhibition of human recombinant N-terminal His-tagged DTT-activated caspase-4 expressed in Escherichia coli using Ac-LEVD-AMC as substrate preincubated for 30 mins followed by substrate addition by fluorescence assay