Spontaneous Chiral Symmetry Breaking in a Random, Driven Chemical System

Abstract

Living systems have evolved to efficiently consume available energy sources using an elaborate cir-cuitry of chemical reactions, which are puzzlingly restricted to specific chiral configurations. While autocatalysis is known to induce such chiral symmetry breaking, whether this might also arise in a more general class of non-autocatalytic chemical networks—by mere virtue of energy source exploitation—is a sensible yet underappreciated possibility. In this work, we examine this question within a model of randomly-generated complex chemical networks and show that chiral symmetry breaking may occur spontaneously and generically by harnessing energy sources from external environmental drives. Key to this transition are intrinsic fluctuations of achiral-to-chiral reactions and tight matching of system configurations to the environmental drive which, together, amplify and sustain diverged enantiomer distributions. The results thus demonstrate a generic mechanism in which energetic drives may give rise to homochirality in an otherwise totally symmetrical environment.