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Abstract
Living systems are characterised by an ability to sustain chemical
reaction networks far-from-equilibrium. It is likely that life first arose
through a process of continual disruption of equilibrium states in recursive
reaction networks, driven by periodic environmental changes allowing the
emergence of a memory. Herein, we report the emergence of proto-enzymatic
function from recursive polymerisation reactions using amino acids and glycolic
acid over four wet-dry cycles. Reactions are kept out of equilibrium by
diluting products 9:1 in fresh starting solution at the end of each recursive
cycle, and the development of complex high molecular weight species is explored
using a new metric, the Mass Index, which allows the complexity of the system
to be explored as a function of cycle. This process is carried out on a range
of different mineral environments. We explore the hypothesis that disrupting
equilibrium via recursive cycling
imposes a selection pressure and subsequent boundary conditions on products,
which may otherwise be prone to uncontrolled combinatorial explosion. After
just four reaction cycles, product mixtures from recursive reactions exhibit
greater catalytic activity and truncation of product space towards higher
molecular weight species compared to non-recursive controls.
