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Published on: October 25, 2017
Dynamics of loop formation in a semiflexible polymer
1Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India. poulose@ualberta.ca
Summary
This study models semiflexible polymer loop formation, finding loop closure times decrease for short chains but increase for longer ones, with a minimum time at intermediate lengths.
Area of Science:
- Polymer Physics
- Statistical Mechanics
- Biophysics
Background:
- Loop formation and opening are crucial in biological processes.
- Studies on flexible polymer loops are abundant, but semiflexible polymer loop dynamics are less explored.
- Previous work investigated semiflexible loop opening dynamics in the short chain limit.
Purpose of the Study:
- To investigate the loop formation dynamics of semiflexible polymer chains.
- To model loop formation as a diffusion-controlled reaction.
- To analyze the dependence of loop formation time on polymer chain length.
Main Methods:
- Utilized an approximate model for semiflexible polymers in the rod limit.
- Employed the Wilemski-Fixman closure approximation with a sink function.
- Performed a detailed multidimensional analysis to calculate closing times.
Main Results:
- Loop formation time decreases with contour length for short chains.
- For longer chains, loop formation time increases with length, following a power law.
- A minimum loop formation time was observed at intermediate chain lengths (Lm ≈ 2.2-2.4).
Conclusions:
- The study provides a theoretical framework for understanding semiflexible polymer loop formation.
- The findings reveal a non-monotonic dependence of loop formation time on chain length.
- This multidimensional analysis offers novel insights into a complex polymer dynamics process.
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