Please use this identifier to cite or link to this item:
http://hdl.handle.net/2289/3620
Title: | Free energy of twisted semiflexible polymers |
Authors: | Sinha, Supurna |
Issue Date: | Jun-2008 |
Publisher: | American Physical Society |
Citation: | Physical Review E, 2008, Vol.77, 061903 |
Abstract: | We investigate the role of fluctuations in single-molecule measurements of torque-link (t-lk) curves. For semiflexible polymers of finite persistence length (i.e., polymers with contour length L comparable to the persistence length LP), the torque versus link curve in the constant-torque (isotorque) ensemble is distinct from the one in the constant-link (isolink) ensemble. Thus, one encounters the conceptually interesting issue of a “free energy of transition†in switching ensembles while making torque-link measurements. We predict the dependence on the semiflexibility parameter beta=L/LP of this extra contribution to the free energy, which shows up as an area in the torque-link plane. This can be tested against future torque-link experiments with single biopolymers. We bring out the inequivalence of torque-link curves for a stiff polymer and present explicit analytical expressions for the distinct torque-link relations in the two ensembles and the free-energy difference in switching ensembles in this context. The predictions of our work can be tested against single-molecule experiments on torsionally constrained biopolymers. |
Description: | Open Access |
URI: | http://hdl.handle.net/2289/3620 |
ISSN: | E-ISSN: 1550-2376 P-ISSN: 1539-3755 |
Alternative Location: | http://dx.doi.org/10.1103/PhysRevE.77.061903 http://arxiv.org/abs/0805.2458 |
Copyright: | 2008 The American Physical Society |
Appears in Collections: | Research Papers (TP) |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
2008 PRE V77 061903.pdf | Open Access | 86.21 kB | Adobe PDF | View/Open |
Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.