https://doi.org/10.1140/epjb/e2010-00062-1
Modulational instability in the anharmonic Peyrard-Bishop model of DNA
1
Laboratory of Mechanics, Department
of Physics, Faculty of Science, University of Yaounde I, P.O. Box 812, Yaounde, Cameroon
2
The African Institute for Mathematical Sciences, 6-8 Melrose Rd, Muizenberg 7945, South Africa
3
Condensed Matter Laboratory, Department of Physics, Faculty of Science, University of Douala, P.O. Box 24157, Douala, Cameroon
Corresponding author: contab408@hotmail.com
Received:
15
May
2009
Revised:
21
September
2009
Published online:
23
February
2010
We report on the presence of modulational instability and the generation of soliton-like excitations in DNA nucleotides. Taking the Peyrard-Bishop-Dauxois model of DNA dynamics as an example, we show that the original difference equation for the DNA dynamics can be reduced to the Salerno equation. We derive the MI criterion in this case. The effect of the anharmonic stacking term on the domain of instability/stability is pointed out. Numerical simulations show the validity of the analytical approach with the generation of wave packets provided that the wave numbers fall in the instability domain. The impact of the anharmonic stacking interactions is investigated and these are found to give rise to a spectrum of behaviours which corroborates experimental facts.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2010
