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Two Adhesive Sites Can Enhance the Knotting Probability of DNA.

ABSTRACT: Self-entanglement, or knotting, is entropically favored in long polymers. Relatively short polymers such as proteins can knot as well, but in this case the entanglement is mainly driven by fine-tuned, sequence-specific interactions. The relation between the sequence of a long polymer and its topological state is here investigated by means of a coarse-grained model of DNA. We demonstrate that the introduction of two adhesive regions along the sequence of a self-avoiding chain substantially increases the probability of forming a knot.

SUBMITTER: Najafi S

PROVIDER: S-EPMC4489926 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Two Adhesive Sites Can Enhance the Knotting Probability of DNA.

Najafi Saeed S Potestio Raffaello R

PloS one 20150702 7

Self-entanglement, or knotting, is entropically favored in long polymers. Relatively short polymers such as proteins can knot as well, but in this case the entanglement is mainly driven by fine-tuned, sequence-specific interactions. The relation between the sequence of a long polymer and its topological state is here investigated by means of a coarse-grained model of DNA. We demonstrate that the introduction of two adhesive regions along the sequence of a self-avoiding chain substantially increa ...[more]

PMID: 26136125

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