Programming Multistationarity in Chemical Replication Networks

Abstract

Systems Chemistry generates platforms for studying the emergence of function in networks operating far from equilibrium. In this area, we have previously used experiments and simulations towards characterization and manipulation of small peptide‐based networks, driven by reversible self‐replication processes, that exhibit bistability. We now show how coupling two such networks, each exhibiting bistability, yields new dynamic systems that reach multiple (up to four) steady states. Furthermore, we demonstrate how such multistationarity, rarely analyzed before, can be systematically programmed and tuned. Our results suggest that the key to mimic biological complexification lies not only in the applied network size, the number of molecules involved, or even in the emergence of elaborate structures, but also in the network nature and topology.

Self-Reproduction and Darwinian Evolution in Autocatalytic Chemical Reaction Systems

“…Furthermore, higher-order autocatalysis has also been observed in systems using DNA [ 46 ] (Note: while higher-order growth and frequency-dependent selection of DNA sequences was shown in [ 46 ] using a theoretical model of autocatalytic templates based on ligation reactions, the experimental demonstration uses a highly evolved enzyme to enhance the reaction speeds and is not autocatalytic.) or peptide template-ligation systems [ 47 ]. Generally speaking, in reaction networks comprised of multiple catalyzed reaction steps, higher-order autocatalytic reaction dynamics could appear.…”

Entropic analysis of bistability and the general evolution criterion

“…(8), and the exchange entropy per unit volume, due to the volumetric open flow Eqs. (16)(17)(18)(19), is 27 1 RV…”

“…Y may stand for A, X or B, respectively, depending on the input/output flow configuration, Eqs. (16)(17)(18)(19), of the model.…”

“…Such dynamical properties are believed to be at the core of the proper functioning of biochemical reaction networks and of living systems. Bistable behavior has been demonstrated and explored in depth in biochemical and in chemical networks [11][12][13][14][15][16][17][18] . The great interest in bistability and switching is due, in large part, to the conviction that systems exhibiting multistability, bifurcations play a key role in the function of living systems 19 .…”

“…The E E E i correspond to subsets, or combinations, of several of the unidirectional reactions in Eqs. (3,4,(16)(17)(18)(19). Some of these EFMs may involve the coupling of the pseudoreaction fluxes with the chemical transformations, and may not necessarily include simultaneously both the forward and reverse steps of a specific chemical reaction.…”