Environmental control programs the emergence of distinct functional ensembles from unconstrained chemical reactions

Abstract

Many approaches to the origin of life focus on how the molecules found in biology might be made in the absence of biological processes, from the simplest plausible starting materials. Another approach could be to view the emergence of the chemistry of biology as process whereby the environment effectively directs “primordial soups” toward structure, function, and genetic systems over time. This does not require the molecules found in biology today to be made initially, and leads to the hypothesis that environment can direct chemical soups toward order, and eventually living systems. Herein, we show how unconstrained condensation reactions can be steered by changes in the reaction environment, such as order of reactant addition, and addition of salts or minerals. Using omics techniques to survey the resulting chemical ensembles we demonstrate there are distinct, significant, and reproducible differences between the product mixtures. Furthermore, we observe that these differences in composition have consequences, manifested in clearly different structural and functional properties. We demonstrate that simple variations in environmental parameters lead to differentiation of distinct chemical ensembles from both amino acid mixtures and a primordial soup model. We show that the synthetic complexity emerging from such unconstrained reactions is not as intractable as often suggested, when viewed through a chemically agnostic lens. An open approach to complexity can generate compositional, structural, and functional diversity from fixed sets of simple starting materials, suggesting that differentiation of chemical ensembles can occur in the wider environment without the need for biological machinery.

The Future of Origin of Life Research: Bridging Decades-Old Divisions

“…could then be varied. There are means to attempt such simulations in the laboratory today, where collecting vast amounts of data is possible [173]. This data can be analysed and incorporated into the computational models which then, in turn, can shed more light on what laboratory experiments should be attempted.…”

Emergence of Function and Selection from Recursively Programmed Polymerisation Reactions in Mineral Environments

“…In previous work, we had examined the ability of minerals and salts to influence the product distribution of similar uncontrolled condensation reactions. [18] Minerals and other solid substrates have been studied extensively for their ability to concentrate amino acids on their surface,c atalyse aqueous peptide polymerisation, [19,20] and enrich depsipeptides for peptide bonds. [21] Products were characterised in afunctional assay and by mass spectrometry at the end of each reaction cycle ( Figure 1).…”

Polyesters as a Model System for Building Primitive Biologies from Non-Biological Prebiotic Chemistry

“…It is unclear whether the earliest catalysts were composed exclusively of biomolecules, or what catalytic functions primitive polymers would need to accomplish. Though it is complicated to study the abiological emergence of functional polymers due to uncertainties about the relevant environmental conditions and reactant availability, various screening and dynamic combinatorial techniques [24,[93][94][95][96][97] may be useful to probe the properties of complex chemical systems. Nevertheless, understanding the potential contribution of the likely diversity of prebiotic organic chemistry on early Earth to contribute to life's emergence is a worthy enterprise.…”