Isotope effect analyses provide evidence for an altered transition state for RNA 2′-O-transphosphorylation catalyzed by Zn2+

Abstract

Solvent D₂O and ¹⁸O kinetic isotope effects on RNA 2′-O-transphosphorylation catalyzed by Zn²⁺ demonstrate an altered transition state relative to specific base catalysis. A recent model from DFT calculations involving inner sphere coordination to the non-bridging and leaving group oxygens is consistent with the data.