Europhys. Lett.
Volume 47, Number 2, July 1999
Page(s) 171 - 174
Section Atomic and molecular physics
Published online 01 September 2002
DOI: 10.1209/epl/i1999-00368-1

Europhys. Lett, 47 (2), pp. 171-174 (1999)

Dynamics of taut DNA chains

F. Brochard-Wyart 1, A. Buguin 1 and P. G. de Gennes 2

1 Laboratoire PCC, Institut Curie
11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France
2 Collège de France - 11 place Marcellin Berthelot, 75005 Paris Cedex 05, France

(received 30 October 1998; accepted in final form 12 May 1999)

PACS. 36.20${\rm -r}$ - Macromolecules and polymer molecules.
PACS. 87.15${\rm -v}$ - Biomolecules: structure and physical properties.


We discuss the dynamics of stretched DNA chains, subjected to a tension force f, in a "taut'' regime where $\varphi=fl_{\rm p0}/k_{\rm B} T\gt 1$ ($l_{\rm p0}$ being the unperturbed persistence length). We deal with two variables: the local transverse displacements u, and the longitudinal position of a monomer $u_\parallel$. The variables u and $u_\parallel$ follow two distinct Rouse equations, with diffusion coefficients $D_\perp=f/\eta$ (where $\eta$ is the solvent viscosity) and $D_\parallel=4\varphi^{1/2}D_\perp$.

We apply these ideas to a discussion of various transient regimes.


Copyright EDP Sciences