Armand Despons - ESPCI Paris
ARN Seminar Thu Oct 31, 9h30 CET
Autocatalysis, the ability of a chemical system to make more of itself, is a crucial feature in metabolism and is speculated to have played a decisive role in the origin of life. Nevertheless, how autocatalytic systems behave far from equilibrium remains unexplored. In this work, we elaborate on recent advances regarding the stoichiometric characterization of autocatalytic networks, particularly their absence of mass-like conservation laws, to study how this topological feature influences their nonequilibrium behavior. Building upon the peculiar topology of autocatalytic networks, we derive a decomposition of the chemical fluxes, which highlights the existence of productive modes in their dynamics. These modes produce the autocatalysts in net excess and require the presence of external fuel/waste species to operate. Relying solely on topology, the fluxes decomposition holds under broad conditions and, in particular, do not require steady-state or elementary reactions. Additionally, we show that once externally controlled, the non-conservative forces brought by the external species do not act on these productive modes. This must be considered when one is interested in the thermodynamics of open autocatalytic networks. Specifically, we show that an additional term must be added to the semigrand free-energy. Finally, from the thermodynamical potential, we derive the thermodynamical cost associated with the production of autocatalysts.
References:
[1] Nonequilibrium properties of autocatalytic networks (2024), Armand Despons, PRE - in review, arxiv.org/abs/2404.03347
[2 Structural constraints limit the regime of optimal flux in autocatalytic reaction networks (2024) Despons, A., De Decker, Y. & Lacoste, D. Commun Phys 7, 224. doi.org/10.1038/s42005-024-01704-8
To attend the autocatalysis in reaction networks seminar (ARN seminar), or for more information, please visit: researchseminars.org/seminar/AutocatalysisRN