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Title: Scaling regimes for wormlike chains confined to cylindrical surfaces under tension
We compute the free energy of confinement F for a wormlike chain (WLC), with persistence length lp, that is confined to the surface of a cylinder of radius R under an external tension f using a mean field variational approach. For long chains, we analytically determine the behavior of the chain in a variety of regimes, which are demarcated by the interplay of lp, the Odijk deflection length (ld = (R2lp)1/3), and the Pincus length (lf = kBT/f, with kBT being the thermal energy). The theory accurately reproduces the Odijk scaling for strongly confined chains at f = 0, with F ∼ Ll−1/3p R−2/3. For moderate values of f, the Odijk scaling is discernible only when lp   R for strongly confined chains. Confinement does not significantly alter the scaling of the mean extension for sufficiently high tension. The theory is used to estimate unwrapping forces for DNA from nucleosomes.  more » « less
Award ID(s):
2019745
PAR ID:
10512510
Author(s) / Creator(s):
;
Publisher / Repository:
The European Physical Journal E
Date Published:
Journal Name:
The European Physical Journal E
Volume:
47
Issue:
1
ISSN:
1292-8941
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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