Related Experiment Video
Updated: May 12, 2026
06:45
Force Spectroscopy of Single Protein Molecules Using an Atomic Force Microscope
Published on: February 28, 2019
Direct force measurement of single DNA-peptide interactions using atomic force microscopy
Ji W Chung1, Dongjin Shin, June M Kwak
1Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
Journal of Molecular Recognition : JMR
|April 19, 2013
Summary
Engineered peptides can bind DNA sequences with high affinity and stability. This study measured DNA-peptide interactions at the single-molecule level, revealing strong, sequence-specific binding for potential nanostructure applications.
Area of Science:
- Biophysics
- Molecular Biology
- Nanotechnology
Background:
- Engineered peptides offer precise molecular recognition capabilities.
- Understanding DNA-peptide interactions is crucial for nanobiotechnology.
Purpose of the Study:
- To quantify the single-molecule interactions between a miniature engineered peptide (p007) and DNA.
- To characterize the binding affinity, rupture force, and unbinding kinetics of this DNA-peptide complex.
Main Methods:
- Atomic force microscopy (AFM) was employed for single-molecule force measurements.
- Kinetic analysis involved fitting rupture forces to pulling rates.
Main Results:
- The engineered peptide (p007) demonstrated specific recognition of the ATGAC DNA sequence with nanomolar affinity.
- An average rupture force of 42.1 pN was recorded, comparable to strong biological interactions.
- Analysis revealed a single energy barrier, suggesting stable binding, with a dissociation rate (koff) lower than similar systems.
Conclusions:
- The miniature engineered peptide exhibits strong, sequence-specific DNA binding.
- The observed stability suggests potential for p007 in creating robust DNA-protein hybrid nanostructures.
- This work advances the design of peptide-based DNA-binding agents for nanotechnology.
