Selection for photocatalytic function through Darwinian evolution of synthetic self-replicators

Abstract

The onset of Darwinian evolution represents a key step in the transition of chemical systems into living ones. Furthermore, Darwinian evolution is a tremendously powerful engine of invention, but one that has remained underdeveloped in synthetic chemical systems. Here we show the emergence of Darwinian evolution in two systems of self-replicating molecules in which natural selection favours replicator mutants best capable of catalysing the production of the precursors required for their own replication. Selection occurs based on the ability of the mutants to activate a photocatalyst as a cofactor that produces singlet oxygen which, in turn, enhances the rate by which peptide-based dithiol building blocks are converted into disulfide-based replicator precursors. Selection is based on a functional trait (catalytic activity), opening up Darwinian evolution as a tool for catalyst development. This work functionally integrates self-replication with protometabolism and Darwinian evolution, marking a further advance in the de novo synthesis of life. (Figure presented.).