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Synthetic Condensates and Cell-Like Architectures from Amphiphilic DNA Nanostructures

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Published on: May 31, 2024

DNA stretching and multivalent-cation-induced condensation.

Yevgeni Sh Mamasakhlisov¹, Brian A Todd, Artem V Badasyan

¹Department of Molecular Physics, Yerevan State University, 1 Al Manougian Str, Yerevan 375025, Armenia.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics

|November 13, 2009

Summary

This summary is machine-generated.

We developed a statistical model for polymer compaction under tension, explaining how DNA condenses with multivalent cations. This model predicts a first-order transition for long polymers and a broader transition for shorter or varied chains.

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Area of Science:

Statistical mechanics
Polymer physics
Biophysics

Background:

Measurements on stretched double-stranded DNA (dsDNA) in the presence of multivalent cations provide experimental motivation.
Semiflexible polymers exhibit complex behavior under tension and in solution.

Purpose of the Study:

To develop a statistical mechanical model for the compaction of insoluble semiflexible polymers under tension.
To determine the order of the extended-to-compact transition.
To interpret the magnitude and tension interval of polymer compaction.

Main Methods:

A mean-field approach is employed to model polymer behavior.
The model analyzes the transition from an extended to a compact state.
Statistical mechanics principles are applied to understand polymer condensation.

Main Results:

Compaction is a first-order transition for infinitely long homogeneous polymers, occurring at a specific tension.
For finite-length or heterogeneous polymers, the compaction transition occurs over an interval of tension.
The model provides interpretations for experimental results in terms of microscopic parameters.

Conclusions:

The developed statistical mechanical model accurately describes polymer compaction under tension.
The model elucidates the role of polymer length and heterogeneity in the compaction transition.
It offers a theoretical framework to link single-molecule experiments to fundamental polymer properties.