Enhanced diffusion of molecular motors in the presence of adenosine triphosphate and external force

TL;DR

This paper presents a theoretical model showing that molecular motor diffusion can be enhanced by external force and ATP-related chemical reactions, with potential implications for biological motors like F1-ATPase.

Contribution

A simple stochastic model demonstrating diffusion peaks of molecular motors under force and ATP influence, providing insights into motor behavior and potential experimental observations.

Findings

Diffusion coefficient exhibits peaks as a function of external force.

Mechanism of diffusion enhancement linked to stochastic potential switching.

Discussion of observing this effect in biological rotary motors like F1-ATPase.

Abstract

The diffusion of a molecular motor in the presence of a constant external force is considered on the basis of a simple theoretical model. The motor is represented by a Brownian particle moving in a series of parabolic potentials placed periodically on a line, and the potential is switched stochastically from one parabola to another by a chemical reaction, which corresponds to the ATP hydrolysis or synthesis in motor proteins. It is found that the diffusion coefficient as a function of the force exhibits peaks. The mechanism of this diffusion enhancement and the possibility of observing it in F1-ATPase, a biological rotary motor, are discussed.