Hairpins in the conformations of a confined polymer
Journal article, 2018

If a semiflexible polymer confined to a narrow channel bends around by 180 degrees, the polymer is said to exhibit a hairpin. The equilibrium extension statistics of the confined polymer are well understood when hairpins are vanishingly rare or when they are plentiful. Here, we analyze the extension statistics in the intermediate situation via experiments with DNA coated by the protein RecA, which enhances the stiffness of the DNA molecule by approximately one order of magnitude. We find that the extension distribution is highly non-Gaussian, in good agreement with Monte-Carlo simulations of confined discrete wormlike chains. We develop a simple model that qualitatively explains the form of the extension distribution. The model shows that the tail of the distribution at short extensions is determined by conformations with one hairpin. (C) 2018 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license


E. Werner

University of Gothenburg

A. Jain

University of Minnesota

A. Muralidhar

University of Minnesota

Karolin Frykholm

Chalmers, Biology and Biological Engineering, Chemical Biology

T. St Clere Smithe

University of Gothenburg

Joachim Fritzsche

Chalmers, Physics, Chemical Physics

Fredrik Westerlund

Chalmers, Biology and Biological Engineering, Chemical Biology

K. D. Dorfman

University of Minnesota

B. Mehlig

University of Gothenburg


1932-1058 (ISSN)

Vol. 12 2 024105

Areas of Advance

Nanoscience and Nanotechnology

Subject Categories

Physical Chemistry






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