Catalytic Metal Ion-Substrate Coordination during Nonenzymatic RNA Primer Extension.

ABSTRACT: Nonenzymatic template-directed RNA copying requires catalysis by divalent metal ions. The primer extension reaction involves the attack of the primer 3'-hydroxyl on the adjacent phosphate of a 5'-5'-imidazolium-bridged dinucleotide substrate. However, the nature of the interaction of the catalytic metal ion with the reaction center remains unclear. To explore the coordination of the catalytic metal ion with the imidazolium-bridged dinucleotide substrate, we examined catalysis by oxophilic and thiophilic metal ions with both diastereomers of phosphorothioate-modified substrates. We show that Mg²⁺ and Cd²⁺ exhibit opposite preferences for the two phosphorothioate substrate diastereomers, indicating a stereospecific interaction of the divalent cation with one of the nonb

SUBMITTER: Fang Z 

PROVIDER: S-EPMC11027144 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature