corner
corner

Phys. Rev. E 68, 061909 (2003) [14 pages]

Thermal denaturation of a helicoidal DNA model

Download: PDF (421 kB) Buy this article Export: BibTeX or EndNote (RIS)

Maria Barbi*
Laboratoire de Physique Théorique des Liquides, Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05, France

Stefano Lepri
Istituto Nazionale per la Fisica della Materia, UdR Firenze, via G. Sansone 1, 50019 Sesto Fiorentino, Italy

Michel Peyrard
Laboratoire de Physique, École Normale Supérieure de Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France

Nikos Theodorakopoulos§
Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, Vasileos Constantinou 48, Athens 11635, Greece

Received 17 July 2003; published 23 December 2003

We study the static and dynamical properties of DNA in the vicinity of its melting transition, i.e., the separation of the two strands upon heating. The investigation is based on a simple mechanical model which includes the helicoidal geometry of the molecule and allows an exact numerical evaluation of its thermodynamical properties. Dynamical simulations of long-enough molecular segments allow the study of the structure factors and of the properties of the denaturated regions. Simulations of finite chains display the hallmarks of a first order transition for sufficiently long-ranged stacking forces although a study of the model’s “universality class” strongly suggests the presence of an “underlying” continuous transition.

© 2003 The American Physical Society

URL:
http://link.aps.org/doi/10.1103/PhysRevE.68.061909
DOI:
10.1103/PhysRevE.68.061909
PACS:
87.15.Aa, 05.20.-y

*Electronic address: barbi@lptl.jussieu.fr

Electronic address: stefano.lepri@unifi.it

Electronic address: Michel.Peyrard@ens-lyon.fr

§Electronic address: nth@eie.gr