Substrate specificity for catalysis of phosphodiester cleavage by a dinuclear Zn(ii) complex

Abstract

The 2.4 kcal mol⁻¹ greater stabilization of the transition state for cleavage of the minimal substrate HpPNP compared to the nucleoside substrate UpPNP by the efficient dinuclear metal ion catalyst Zn₂(L₂O) provides evidence that access to the cationic core of Zn₂(L₂O) is sterically blocked for the bulkier nucleoside substrates, a flaw that will need to be dealt with in later generations of metal ion catalysts of RNA cleavage.