Modelling proton transfer in water molecule chains

TL;DR

This paper presents a simplified analytical and numerical model of proton transfer in water chains within biological channels, highlighting nonlinear structures that enable faster proton transport, with implications for biological systems.

Contribution

The study introduces a discrete 1D model capturing proton hopping and oscillations in water chains, revealing nonlinear solitary structures that enhance proton transport efficiency.

Findings

Identification of nonlinear solitary transport structures

Faster proton transport due to nonlinear effects

Implications for biological proton transfer mechanisms

Abstract

The process of protons transport in molecular water chains is of fundamental interest for many biological systems. Although many features of such systems can be analyzed using large-scale computational modeling, other features are better understood in terms of simplified model problems. Here we have tested, analytically and numerically, a model describing the classical proton hopping process in molecular water chains. In order to capture the main features of the proton hopping process in such molecular chains, we use a simplified model for our analysis. In particular, our discrete model describes a 1D chain of water molecules situated in an external protein channel structure, and each water molecule is allowed to oscillate around its equilibrium point in this system, while the protons are allowed to move along the line of neighboring oxygen atoms. The occurrence and properties of nonlinear solitary transport structures, allowing for much faster proton transport, are discussed, and the possible implications of these findings for biological systems are emphasized.