Related Experiment Video
Updated: Mar 1, 2026
11:55
Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
12.2K
Discriminating Residue Substitutions in a Single Protein Molecule Using a Sub-nanopore
Zhuxin Dong1, Eamonn Kennedy1, Mohammad Hokmabadi1
1Department of Electrical Engineering and ‡Departments of Electrical Engineering and Biological Science, University of Notre Dame , Notre Dame, Indiana 46556, United States.
ACS Nano
|May 25, 2017
Summary
Researchers used sub-nanopores to sequence proteins. They found that these tiny pores can detect differences in amino acid sequences by measuring volume changes, paving the way for single-molecule protein analysis.
Area of Science:
- Nanotechnology
- Biophysics
- Proteomics
Background:
- Sub-nanometer pores can be fabricated in inorganic membranes.
- Amino acid residues are approximately the size of these sub-nanopores.
Purpose of the Study:
- To explore the potential of sub-nanopores for sequencing proteins.
- To investigate protein translocation dynamics and residue discrimination within a sub-nanopore.
Main Methods:
- Atomic force microscopy was used to impel denatured histone proteins through a sub-nanopore.
- Measurements of force and electrical current blockade were recorded during translocation.
- Analysis of translocation kinetics and fluctuation patterns in force and current data.
Main Results:
- Sodium dodecyl sulfate (SDS) was cleaved from proteins during translocation, requiring a large force to retract.
- Protein translocation exhibited either frictionless sliding or slip-and-stick behavior.
- Fluctuation patterns in force and current correlated with residue spacing and occluded volume (0.1 nm³).
Conclusions:
- Sub-nanopores are sensitive enough to discriminate single amino acid substitutions in proteins.
- This technique allows for the analysis of protein sequences at the single-molecule level.
- The method holds promise for future protein sequencing applications.
