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arXiv · 1606.07221

Packaging stiff polymers in small containers: A molecular dynamics study

D. C. Rapaport
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Abstract

The question of how stiff polymers are able to pack into small containers is particularly relevant to the study of DNA packaging in viruses. A reduced version of the problem based on coarse-grained representations of the main components of the system -- the DNA polymer and the spherical viral capsid -- has been studied by molecular dynamics simulation. The results, involving longer polymers than in earlier work, show that as polymers become more rigid there is an increasing tendency to self-organize as spools that wrap from the inside out, rather than the inverse direction seen previously. In the final state, a substantial part of the polymer is packed into one or more coaxial spools, concentrically layered with different orientations, a form of packaging achievable without twisting the polymer.

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D. C. Rapaport. 2016-06-23. Packaging stiff polymers in small containers: A molecular dynamics study. https://doi.org/10.1103/physreve.94.030401

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