1n32
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Structure of the Thermus thermophilus 30S ribosomal subunit bound to codon and near-cognate transfer RNA anticodon stem-loop mismatched at the first codon position at the a site with paromomycin
OverviewOverview
A structural and mechanistic explanation for the selection of tRNAs by the, ribosome has been elusive. Here, we report crystal structures of the 30S, ribosomal subunit with codon and near-cognate tRNA anticodon stem loops, bound at the decoding center and compare affinities of equivalent, complexes in solution. In ribosomal interactions with near-cognate tRNA, deviation from Watson-Crick geometry results in uncompensated desolvation, of hydrogen-bonding partners at the codon-anticodon minor groove. As a, result, the transition to a closed form of the 30S induced by cognate tRNA, is unfavorable for near-cognate tRNA unless paromomycin induces part of, the rearrangement. We conclude that stabilization of a closed 30S, conformation is required for tRNA selection, and thereby structurally, rationalize much previous data on translational fidelity.
About this StructureAbout this Structure
1N32 is a Protein complex structure of sequences from Thermus thermophilus with PAR, MG and ZN as ligands. Full crystallographic information is available from OCA.
ReferenceReference
Selection of tRNA by the ribosome requires a transition from an open to a closed form., Ogle JM, Murphy FV, Tarry MJ, Ramakrishnan V, Cell. 2002 Nov 27;111(5):721-32. PMID:12464183
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