https://doi.org/10.1140/epjb/e2013-40467-6
Regular Article
Nonlinear wave trains in three-strand α-helical protein models
1
Laboratory of Biophysics, Department of Physics, Faculty of
Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon
2
Condensed Matter Laboratory, Department of Physics, Faculty of
Science, University of Douala, P.O. Box 24157, Douala, Cameroon
3
Laboratory of Mechanics, Department of Physics, Faculty of
Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon
a
e-mail: conrad@aims.ac.za
Received: 8 May 2013
Received in final form: 26 June 2013
Published online: 9 September 2013
Realistic models of α-helix proteins are composed of three covalently-bonded strands, each of which is made of hydrogen-bonded peptide units. The modulational instability analysis of such complex molecular systems is carried out in this work. We show that the exciton-vibron coupling parameter contributes to the explosion and expansion of instability regions. The right choice of the modulational instability parameters leads to the formation of excitonic modulated pulse-like structures. It is argued that covalent bonds are compressed during the process of energy transport, while hydrogen bond oscillations display regular trains of breather-like objects. We also argue that the probable way of energy transport, from modulational instability, is through hydrogen bonds.
Key words: Statistical and Nonlinear Physics
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2013
