Isotope effect analyses provide evidence for an altered transition state for RNA 2'-O-transphosphorylation catalyzed by Zn(2+).
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ABSTRACT:
SUBMITTER: Zhang S
PROVIDER: S-EPMC4916458 | biostudies-literature | 2016 Mar
REPOSITORIES: biostudies-literature
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Isotope effect analyses provide evidence for an altered transition state for RNA 2'-O-transphosphorylation catalyzed by Zn(2+).
Zhang Shuming S Gu Hong H Chen Haoyuan H Strong Emily E Ollie Edward W EW Kellerman Daniel D Liang Danni D Miyagi Masaru M Anderson Vernon E VE Piccirilli Joseph A JA York Darrin M DM Harris Michael E ME
Chemical communications (Cambridge, England) 20160301 24
Solvent D2O and (18)O kinetic isotope effects on RNA 2'-O-transphosphorylation catalyzed by Zn(2+) 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. ...[more]
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