Simultaneous formation of peptides and RNA via prebiotic cross-catalytic enhancement

Abstract

Nucleoside triphosphates, cyclic monophosphates and amino acids are hypothesized to have been present together in the prebiotic milieu. Earlier studies have demonstrated the importance of their phosphorylation to result in oligomers. In this study, we characterized the cross-catalytic effect of oligomerization stemming from the simultaneous presence of nucleotide and amino acids, two biochemically important monomers, in a reaction mixture, and discuss its implications for biomolecular evolution. Intrinsically phosphorylated linear or cyclic nucleotides (ATP and cAMP, respectively), when mixed with glycine in a one-pot- reaction under prebiotically pertinent conditions, resulted in peptides and oligonucleotides.Mass spectrometry analysis indicated the formation of oligomers, with an increase in relative abundance observed in certain reaction scenarios when compared to reactions that involved only oligomerization of the individual monomer. The reason for this enhancement in case of both the oligomer types, was the formation of a reactive intermediate, an aminoacylated-AMP (AMP-aa). We extended this strategy to study amino acids with different side chains to comprehend the properties required for the formation of AMP-aa under our reaction conditions. The nonenzymatic formation of AMP-aa, which resulted in longer oligomers, indicates the plausibility of the emergence of initial steps involved in a primordial aminoacylation or single nucleotide translation system.