A Highly Reactive Imidazolium-Bridged Dinucleotide Intermediate in Nonenzymatic RNA Primer Extension.

ABSTRACT: Because of its importance for the origin of life, the nonenzymatic copying of RNA templates has been the subject of intense study for several decades. Previous characterizations of template-directed primer extension using 5'-phosphoryl-2-methylimidazole-activated nucleotides (2-MeImpNs) as substrates have assumed a classical in-line nucleophilic substitution mechanism, in which the 3'-hydroxyl of the primer attacks the phosphate of the incoming monomer, displacing the 2-methylimidazole leaving group. However, we have found that the initial rate of primer extension depends on the pH and concentration at which the activated monomer is maintained prior to the primer extension reaction. These and other results suggest an alternative mechanism, in which two monomers react with each other to for

SUBMITTER: Walton T 

PROVIDER: S-EPMC6326528 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature