Trapping and transport of charges in DNA by mobile discrete breathers

Abstract

Numerical simulation of trapping and transport of a charged particle (electron or hole) by mobile discrete breathes (mobile DB, MDB) in DNA molecule has been provided. Mobile DBs have been excited by disturbance of displacements or velocities of adjacent nucleotide pairs dislocated near one of fixed ends of the molecule. It is shown that effective forming of a stable quasi-particle “MDB + electron” occurs when a few of nucleotide pairs at the end of DNA are excited. Breathes may be excited by disturbances of displacements and velocities directed both to axis and from axis of the molecule. A wave function of an electron must be located initially in a region of disturbance of the molecule. It has been found that a metastable quasi-particle may be transported at a distance up to 200 of a rise per base pair. The mechanism of transport of a charged particle presented is not in need of an external electric field and may be considered as an alternative one to the polaronic mechanism.