A spatial model of autocatalytic reactions

TL;DR

This paper models autocatalytic reactions within a spatially bounded domain to mimic primitive protocells, revealing large, sustained spatio-temporal oscillations that could influence vesicle division and protocell reproduction.

Contribution

It introduces a stochastic spatial model of autocatalytic reactions showing novel spatio-temporal oscillations relevant to protocell dynamics.

Findings

Large sustained oscillations observed in reaction constituents

Oscillations are spatio-temporal, not just temporal

Potential role in vesicle division and protocell reproduction

Abstract

Biological cells with all of their surface structure and complex interior stripped away are essentially vesicles - membranes composed of lipid bilayers which form closed sacs. Vesicles are thought to be relevant as models of primitive protocells, and they could have provided the ideal environment for pre-biotic reactions to occur. In this paper, we investigate the stochastic dynamics of a set of autocatalytic reactions, within a spatially bounded domain, so as to mimic a primordial cell. The discreteness of the constituents of the autocatalytic reactions gives rise to large sustained oscillations, even when the number of constituents is quite large. These oscillations are spatio-temporal in nature, unlike those found in previous studies, which consisted only of temporal oscillations. We speculate that these oscillations may have a role in seeding membrane instabilities which lead to vesicle division. In this way synchronization could be achieved between protocell growth and the reproduction rate of the constituents (the protogenetic material) in simple protocells.