Atomic force microscopy with nanoscale cantilevers resolves different structural conformations of the DNA double...

Area of Science:

• Biophysics
• Molecular Biology
• Nanotechnology

Background:

• Biomolecular structure and flexibility are key to function.
• Visualizing dynamic DNA structures at the single-molecule level is challenging.

Purpose of the Study:

• To visualize distinct structural conformations of DNA double helix strands.
• To achieve this for single DNA molecules under near-physiological conditions.
• To reduce invasiveness and enhance spatial resolution in atomic force microscopy (AFM).

Main Methods:

• Utilizing atomic force microscopy (AFM) with enhanced spatial resolution.
• Developing a method to identify and track anomalous resonance behavior of nanoscale AFM cantilevers.
• Applying the technique to single DNA molecules under near-physiological conditions.

Main Results:

• Successfully visualized different structural conformations of the two polynucleotide strands in the DNA double helix.
• Demonstrated the ability to observe single DNA molecules in near-physiological conditions.
• Achieved reduced invasiveness and enhanced spatial resolution compared to previous AFM methods.

Conclusions:

• The developed AFM technique provides unprecedented visualization of DNA structural dynamics.
• This advancement offers new insights into the relationship between DNA structure, flexibility, and function.
• Enables detailed studies of DNA at the molecular level under biologically relevant conditions.