Multi-selective one dimensional proton NMR experiments for rapid screening and binding affinity measurements.

Area of Science:

• Biochemistry
• Chemical Biology
• Structural Biology

Background:

• Ligand-based proton NMR screening is crucial for drug lead discovery.
• Severe signal overlap in large chemical mixtures limits current NMR screening methods.
• Advanced NMR techniques are needed to overcome these limitations.

Purpose of the Study:

• To present a novel NMR methodology for overcoming signal overlap in high-throughput screening.
• To apply this method for analyzing compounds binding to Sudlow site I of human serum albumin.
• To accurately determine binding constants of NMR-identified hits.

Main Methods:

• Utilized multi-selective R(1) filtered and COSY or TOCSY experiments to resolve signal overlap.
• Employed a spy molecule and control molecule in proton NMR screening.
• Monitored the intensity of two specific signals for screening.
• Measured relative signal intensities to derive binding constants.

Main Results:

• Successfully applied the NMR methodology to study ligand binding at Sudlow site I of human serum albumin.
• The screening method effectively resolved signal overlap in complex mixtures.
• Derived NMR binding constants showed good agreement with those obtained from ITC and fluorescence spectroscopy for simple competition binding.

Conclusions:

• The developed NMR approach effectively overcomes signal overlap in high-throughput screening.
• This method allows for rapid and accurate determination of NMR-hit binding constants.
• The technique offers a valuable tool for drug lead identification and characterization.