A Familiar Protein-Ligand Interaction Revisited with Multiple Methods.

Area of Science:

• Biochemistry
• Structural Biology
• Biophysics

Background:

• Hen egg white lysozyme (HEWL) interaction with tri-N-acetyl glucosamine is a well-studied system.
• Biophysical methods are crucial for characterizing molecular interactions.

Purpose of the Study:

• To present experiments for detecting and quantifying HEWL-tri-N-acetyl glucosamine interaction.
• To demonstrate the robustness and consistency of common biophysical methods.

Main Methods:

• Thermal shift assay
• Fluorescence intensity
• Microscale thermophoresis
• Isothermal titration calorimetry
• Surface plasmon resonance

Main Results:

• Representative data from practical courses were analyzed.
• Confidence intervals for dissociation constants were calculated for each method.
• High consistency was observed between different methods for this simple system.

Conclusions:

• The presented biophysical methods are robust for quantifying molecular interactions.
• These protocols are suitable for teaching and troubleshooting in a core facility setting.
• Consistent results across multiple techniques validate the interaction characterization.