Lucanthone and Its Derivative Hycanthone Inhibit Apurinic Endonuclease-1 (APE1) by Direct Protein Binding
Figure 8
APE1 binds directly with lucanthone and hycanthone with different affinities.
APE1 protein (100 µg) (ligand) was immobilized on carboxymethyl-5 (CM-5) chip by amine coupling according to manufacturer's instructions. Hycanthone (top figure) (analyte) and lucanthone (analyte) (lower figure) (analyte) at different concentrations (as shown as numbers representing µM values) were tested for binding to APE1 on BAICORE 2000 SPR measurement system available at SUNYSB proteomics core facility. The observed maximum response (RU) was determined by direct curve fitting of the obtained data assuming a 1∶1 interaction model. The third sub figure shows plot of r (RU/RUmax) versus Cfree. Binding studies were carried out 3 times and data presented are representative of those 3 separate experiments.