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PubMed · 12376595

Transition state stabilization by a catalytic RNA.

Peter B Rupert·Archna P Massey·Snorri Th Sigurdsson·Adrian R Ferré-D'Amaré
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Abstract

The hairpin ribozyme catalyzes sequence-specific cleavage of RNA through transesterification of the scissile phosphate. Vanadate has previously been used as a transition state mimic of protein enzymes that catalyze the same reaction. Comparison of the 2.2 angstrom resolution structure of a vanadate-hairpin ribozyme complex with structures of precursor and product complexes reveals a rigid active site that makes more hydrogen bonds to the transition state than to the precursor or product. Because of the paucity of RNA functional groups capable of general acid-base or electrostatic catalysis, transition state stabilization is likely to be an important catalytic strategy for ribozymes.

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Binding SitesCatalysisCrystallizationCrystallography, X-RayHydrogen BondingLigandsModels, MolecularNucleic Acid ConformationOxygenRNA, CatalyticVanadatesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Peter B Rupert, Archna P Massey, Snorri Th Sigurdsson, Adrian R Ferré-D'Amaré. 2002-10-10. Transition state stabilization by a catalytic RNA.. https://doi.org/10.1126/science.1076093

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