Fig. (6). Inhibitor Potency Titration Curves Five compounds were re-tested at titrating concentrations. The five compounds were: aurintricarboxylic acid (ATA), 8,8'-[carbonylbis(imino-3,1-phenylenecarbonylimino)]bis(1,3,5-naphthalene-trisulfonic acid) hexasodium salt (NF-023), 4-[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propoxy]phenoxyacetic acid (L-165,041), SCH-202676 hydrobromide or N-(2,3-diphenyl-1,2,4-thiadiazol-5-(2H)-ylidene)methanamine hydrobromide (SCH HBr), and 6-hydroxyl-DL-DOPA or 2,5-dihydroxy-DL-tyrosine (L-DOPA). A. Using the CP₂₃₄-Luc/ENLYFQC assay, NF-023 and ATA were tested from 0 – 0.2 mM and the other three compounds were tested from 0 – 1 mM. Data are the mean values, N = 3. Error bars are the standard deviation of the mean. B. Using the protein fusion cleavage assay, compounds were tested from 0 – 0.1 mM. Data are the average of N = 2.