Untying of Complex Knots on Stretched Polymers in Elongational Fields

@article{Soh2018UntyingOC,
  title={Untying of Complex Knots on Stretched Polymers in Elongational Fields},
  author={Beatrice W. Soh and Alexander R. Klotz and Patrick S. Doyle},
  journal={Macromolecules},
  year={2018},
  url={https://api.semanticscholar.org/CorpusID:105021310}
}
Knotting is a prevalent phenomenon which occurs in long polymer chains. We perform Brownian dynamics simulations and single-molecule DNA experiments to investigate knot untying in elongational fields that is induced by the knot being convected off the chain. The change in knot size as the knot moves off the chain and unties causes a change in the effective Weissenberg number, which in turn leads to a change in chain extension. Large-scale chain conformational changes are observed in both… 
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Diffusion of knots in nanochannel-confined DNA molecules.

L Langevin dynamics simulations without hydrodynamic interactions are used to probe knot diffusion mechanisms and the time scales governing the evolution and the spontaneous untying of trefoil knots in nanochannel-confined DNA molecules in the extended de Gennes regime to suggest a combination of self-reptation and knot region breathing for the simulated parameters.

Conformational State Hopping of Knots in Tensioned Polymer Chains.

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A theoretical description of the topological disentanglement occurring when torus knots reach the ends of a semiflexible polymer under tension, which shows remarkable agreement between the simulations and the theoretical predictions of the model.

Topological Entanglement of Linear Catenanes: Knots and Threadings

We used molecular dynamics simulations to investigate the self-entanglements of the collapsed linear catenanes. We found two different types of topologically complex states. First, we observed…

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