Modeling molecular motors

TLDR

Molecular motors convert chemical energy into mechanical work, and their collective behavior in large ensembles is of interest. The study aims to develop simple models for isothermal motors operating at small scales in asymmetric environments. The authors present a generic Onsager‑like linear description differing from Carnot engines and explicit single‑motor models highlighting time‑scale and spatial‑activity effects. They report dynamical phase transitions analogous to paramagnetic‑ferromagnetic and liquid‑vapor transitions.

Abstract

The authors present general considerations and simple models for the operation of isothermal motors at small scales, in asymmetric environments. Their work is inspired by recent observations on the behavior of molecular motors in the biological realm, where chemical energy is converted into mechanical energy. A generic Onsager-like description of the linear (close to equilibrium) regime is presented, which exhibits structural differences from the usual Carnot engines. Turning to more explicit models for a single motor, the authors show the importance of the time scales involved and of the spatial dependence of the motor's chemical activity. Considering the situation in which a large collection of such motors operates together. The authors exhibit new features among which are dynamical phase transitions formally similar to paramagnetic-ferromagnetic and liquid-vapor transitions.