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Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects
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Characterization of Inhibitor Binding Through Multiple Inhibitor Analysis: A Novel Local Fitting Method
Thomas V Riera1, Tim J Wigle2, Robert A Copeland3
1Epizyme, Inc., 4th Floor, 400 Technology Square, Cambridge, MA, 02139, USA. triera@epizyme.com.
Methods in Molecular Biology (Clifton, N.J.)
|June 19, 2016
Summary
Understanding how drug inhibitors bind is crucial for drug discovery. New methods analyzing multiple inhibitor experiments help classify novel compounds and characterize binding interactions for better drug development.
Area of Science:
- Biochemistry
- Pharmacology
- Drug Discovery
Background:
- Understanding inhibitor binding modes is critical in early drug discovery, influencing hit finding and prioritization.
- Multiple inhibitor experiments measure enzyme inhibition with two varied inhibitors to reveal compound interactions.
Purpose of the Study:
- To present a novel local curve fitting method for analyzing multiple inhibitor experimental data.
- To demonstrate the utility of IC50 replots for characterizing inhibitor binding interactions.
Main Methods:
- Utilizing simultaneous variation of two inhibitors to measure enzyme inhibition.
- Applying a new local curve fitting method with IC50 replots for data analysis.
- Adapting the Cheng and Prusoff method for analyzing inhibitor-inhibitor interactions.
Main Results:
- The IC50 replot method generates distinct patterns diagnostic of inhibitor interaction types (exclusive, independent, synergistic, antagonistic).
- This method aids in hit classification and characterization of novel inhibitors.
- Demonstrated application using histone methyltransferase EZH2 inhibition by EPZ-5687 and S-adenosylhomocysteine.
Conclusions:
- Multiple inhibitor experiments combined with IC50 replot analysis offer a robust approach to understanding inhibitor binding.
- This method is valuable for hit classification and characterizing novel drug candidates.
- The presented technique enhances drug discovery by providing insights into inhibitor-inhibitor relationships.
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