Role of co-solutes in nonenzymatic RNA replication on prebiotic Earth
The widely accepted 'RNA World' hypothesis presumes that the fundamental roles of catalysis and information transfer were performed by RNA molecules during the origin and early evolution of life on the prebiotic Earth. Although studies from the last few decades were aimed at characterizing prebiotically relevant nonenzymatic polymerization and information transfer reactions of nucleic acids, a crucial aspect of the inherent complexity of the prebiotic environment has rarely been taken into the account thus far. Towards this, during my Ph.D., I analyzed the effect of pertinent co-solutes on the nonenzymatic RNA copying reactions. We observed that the presence of co-solutes adversely affected the fidelity of nonenzymatic copying reactions while using the activated monomers. When similar reactions were tried using nonactivated nucleotides (such as nucleoside 5'- monophosphates) under volcanic geothermal conditions, the formation of prebiotically relevant hybrid polymers
was suggested. In this talk, I would like to underline the importance of factoring in the prebiotic heterogeneity while studying relevant enzyme-free reactions. Our results suggest that it would have had direct implications for the efficient emergence and replication of functional nucleic acid sequences in a complex prebiotic milieu.