Kink solitons in DNA

TL;DR

This paper explores the nonlinear dynamics of DNA, demonstrating the existence of kink and antikink solitons of sine-Gordon type, and proposes experimental methods to observe rotational wave speeds in DNA strands.

Contribution

It introduces a sine-Gordon model for DNA dynamics and suggests experimental approaches to measure rotational wave velocities in single and double stranded DNA.

Findings

Kink and antikink solitons can exist in DNA models.

Rotational wave speeds differ between single and double stranded DNA.

Velocity ratios relate to hydrogen and covalent bond interactions.

Abstract

We here examine the nonlinear dynamics of artificial homogeneous DNA chain relying on the plain-base rotator model. It is shown that such dynamics can exhibit kink and antikink solitons of sine-Gordon type. In that respect we propose possible experimental assays based on single molecule micromanipulation techniques. The aim of these experiments is to excite the rotational waves and to determine their speeds along excited DNA. We propose that these experiments should be conducted either for the case of double stranded (DS) or single stranded (SS) DNA. A key question is to compare the corresponding velocities of the rotational waves indicating which one is bigger. The ratio of these velocities appears to be related with the sign of the model parameter representing ratio of the hydrogen-bonding and the covalent-bonding interaction within the considered DNA chain.