Three Bead Rotating Chain model shows universality in the stretching of proteins

TL;DR

This paper introduces a comprehensive protein model that captures backbone atom details and demonstrates that protein stretching behavior is universal across different structures, validated by Monte Carlo simulations matching experimental data.

Contribution

The study extends the Freely Rotating Chain model by including all key backbone atoms and shows universality in protein stretching behavior through simulation and experimental agreement.

Findings

Force extension plot is universal across proteins.

Model accurately reproduces experimental stretching data.

Universality does not depend on side chains or primary structure.

Abstract

We introduce a model of proteins in which all of the key atoms in the protein backbone are accounted for, thus extending the Freely Rotating Chain model. We use average bond lengths and average angles from the Protein Databank as input parameters, leaving the number of residues as a single variable. The model is used to study the stretching of proteins in the entropic regime. The results of our Monte Carlo simulations are found to agree well with experimental data, suggesting that the force extension plot is universal and does not depend on the side chains or primary structure of proteins.