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DNA Nanotubes as a Versatile Tool to Study Semiflexible Polymers
Published on: October 25, 2017
Disordered, stretched, and semiflexible biopolymers in two dimensions
1Department of Physics, Tamkang University, 151 Ying-chuan, Tamsui 25137, Taiwan, Republic of China. zzhou@mail.tku.edu.tw
Summary
We found that intrinsic sequence-dependent curvature in biopolymers can be simplified under no force but becomes complex under external force. The biopolymer
Area of Science:
- Biophysics
- Polymer Physics
- Soft Matter Physics
Background:
- Biopolymers exhibit intrinsic sequence-dependent curvature.
- Understanding polymer elasticity is crucial for biological processes.
Purpose of the Study:
- To investigate the effects of intrinsic sequence-dependent curvature in a two-dimensional semiflexible biopolymer.
- To determine the conditions under which such a system can be simplified or becomes complex.
Main Methods:
- Exact analytical treatment of a two-dimensional semiflexible biopolymer model.
- Analysis of systems with and without external forces.
- Investigation of sequence disorder effects under varying conditions.
Main Results:
- A system without external force is equivalent to a renormalized system with well-defined curvature and persistence length.
- This equivalence breaks down under external force, with disorder effects depending on averaging order, disorder degree, and boundary conditions.
- Short biopolymers may appear softer, while long polymers under strong force show disorder is immaterial for elasticity.
Conclusions:
- The behavior of intrinsically curved biopolymers is highly dependent on external forces.
- Sequence disorder significantly impacts polymer elasticity, with its effect varying based on experimental conditions.
- A simplified model is insufficient for describing complex biopolymer behavior under force.
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