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PDBsum entry 3i2s
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References listed in PDB file
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Key reference
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Title
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Single-Atom imino substitutions at a9 and a10 reveal distinct effects on the fold and function of the hairpin ribozyme catalytic core.
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Authors
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R.C.Spitale,
R.Volpini,
M.V.Mungillo,
J.Krucinska,
G.Cristalli,
J.E.Wedekind.
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Ref.
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Biochemistry, 2009,
48,
7777-7779.
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PubMed id
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Abstract
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The hairpin ribozyme cleaves a phosphodiester bond within a cognate substrate.
Structural and biochemical data indicate the conserved A9 and A10 bases reside
close to the scissile bond but make distinct contributions to catalysis. To
investigate these residues, we replaced the imino moiety of each base with
N1-deazaadenosine. This single-atom change resulted in an 8-fold loss in k(obs)
for A9 and displacement of the base from the active site; no effects were
observed for A10. We propose that the imino moiety of A9 promotes a key
water-mediated contact that favors transition-state formation, which suggests an
enhanced chemical repertoire for RNA.
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Headers
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