| Assay Method Information | |
| | Inhibition Assay |
| Description: | The initial screen was designed to look at the effect of potential inhibitors on APE1 repair kinetics. The approach can be used as a high throughput screen by choosing a specific timepoint to monitor. The screen utilizes a molecular beacon with a tetrahydrofuran (THF) abasic site within the stem region of a DNA hairpin that has a fluorophore on the 5′-terminus and a quencher on the 3′-terminus (FIG. 2a ). Compounds that had good inhibitory activity in this screen were then retested using a gel based assay to directly measure DNA excision as a function of inhibitor concentration. An example of the molecular beacon screen and the excision assay are shown in FIGS. 2b,c and 2d , respectively.Evidence that Inhibitor Binds Directly to APE1 Evidence that the inhibitors directly bound to APE1 was established using isothermal titration calorimetry (ITC). This method provides thermodynamic information on the binding affinity, stoichiometry and the thermodynamic parameters, i.e., ΔG, ΔH and TΔS. In addition to the studies on the binding of the inhibitor to APE1, it was also confirmed that the inhibitor did not block enzymatic activity by binding to the DNA. |
| Affinity data for this assay | |
|---|---|
| If you find an error in this entry please send us an E-mail | |