Detection of Functional Ligand-Binding Events Using Synchrotron X-Ray Scattering

Abstract

Small-molecule ligands that change the structure of a protein are likely to affect its function, whereas those causing no structural change are less likely to be functional. Wide-angle x-ray scattering (WAXS) can be easily carried out on proteins and small molecules in solution in the absence of chemical tags or derivatives. The authors demonstrate that WAXS is a sensitive probe of ligand binding to proteins in solution and can distinguish between nonfunctional and productive binding. Furthermore, similar ligand-binding modes translate into similar scattering patterns. This approach has high potential as a novel, generic, low-throughput assay for functional ligand binding. ( Journal of Biomolecular Screening 2007:994-998)