Fluctuation Induced Homochirality

TL;DR

This paper introduces a novel mechanism for homochirality in biological systems, showing that stochastic fluctuations and recycling cross inhibition can induce homochirality without autocatalysis.

Contribution

It demonstrates that stochastic effects can lead to homochirality in a system where deterministic models predict symmetry, highlighting the role of fluctuations in chiral symmetry breaking.

Findings

Stochastic master equation predicts complete homochirality.

Fluctuations due to population discreteness are essential.

Recycling cross inhibition aids in symmetry breaking.

Abstract

We propose a new mechanism for the achievment of homochirality in life without any autocatalytic production process. Our model consists of a spontaneous production together with a recycling cross inhibition in a closed system. It is shown that although the rate equations for this system predict no chiral symmetry breaking, the stochastic master equation predicts complete homochirality. This is because the fluctuation induced by the discreteness of population numbers of participating molecules plays essential roles. This fluctuation conspires with the recyling cross inhibition to realize the homochirality.