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bioRxiv · 10.1101/2024.10.02.616211

Cross-catalytic enhancement of peptides and RNA from a common prebiotic activated intermediate

Roy, R.·Sawant, A. A.·Rajamani, S.
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Abstract

Previous origin of life studies have demonstrated the presence of amino acids and nucleotides in the same prebiotic milieu. In this study, we set out to understand the interplay of amino acids with linear or cyclic nucleotides under prebiotically pertinent reaction conditions, especially for its implications for biomolecular evolution. We characterized the cross-catalytic effect of oligomerization, potentially stemming from the simultaneous presence of these two biochemically important monomers. Qualitative and quantitative analysis indicated the formation of longer AMP oligomers and peptides, with 8-10 fold increase in specific reaction scenarios, when compared to reactions that evaluated the monomer oligomerization in isolation. The reason behind such an increase in yield and length, in case of both the oligomers, was the formation of a reactive intermediate. This aminoacylated-AMP (AMP-aa) resulted from a condensation reaction between the nucleotide and the amino acid. We extended this to other amino acids with different R chain characteristics, to comprehend the properties required for the formation of AMP-aa under our reaction conditions. The nonenzymatic formation of these aminoacylated AMP, which in turn resulted in longer oligomers, indicates the plausibility of the emergence of initial steps involved in a primordial translation system.

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Roy, R., Sawant, A. A., Rajamani, S.. 2024-10-02. Cross-catalytic enhancement of peptides and RNA from a common prebiotic activated intermediate. https://doi.org/10.1101/2024.10.02.616211

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