A versatile "multiple fishhooks" approach for the study of ligand-receptor interactions using single-molecule atomic...

Area of Science:

• Biophysics
• Materials Science
• Biochemistry

Background:

• Atomic force microscopy (AFM)-based single-molecule force spectroscopy is powerful for studying ligand-receptor interactions.
• Complex cantilever functionalization and data interpretation hinder widespread AFM application.

Purpose of the Study:

• To present a simplified experimental scheme for AFM single-molecule force spectroscopy.
• To improve the quality and quantity of single-molecule data by simplifying experimental procedures.

Main Methods:

• Developed a "multiple fishhooks" approach using a single polymer chain with multiple ligands.
• Utilized hyaluronan as a pH-tunable polymer backbone for the "multiple fishhooks" handle.
• Validated the strategy with the streptavidin-biotin system.

Main Results:

• Captured multiple single-bond rupture events in single force-extension curves.
• Enabled easy exclusion of non-single-molecule events and nonspecific interactions.
• Achieved results in good agreement with previously reported data for the streptavidin-biotin system.

Conclusions:

• The "multiple fishhooks" approach significantly simplifies AFM-based single-molecule force spectroscopy.
• This method enhances data quality and quantity, making it a versatile tool for studying complex ligand-receptor interactions.
• The use of hyaluronan and simplified labeling offers advantages over previous methods.