2uu9
STRUCTURE OF THE THERMUS THERMOPHILUS 30S RIBOSOMAL SUBUNIT COMPLEXED WITH A VALINE-ASL WITH CMO5U IN POSITION 34 BOUND TO AN MRNA WITH A GUG-CODON IN THE A-SITE AND PAROMOMYCIN.
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OverviewOverview
One of the most prevalent base modifications involved in decoding is, uridine 5-oxyacetic acid at the wobble position of tRNA. It has been known, for several decades that this modification enables a single tRNA to decode, all four codons in a degenerate codon box. We have determined structures, of an anticodon stem-loop of tRNA(Val) containing the modified uridine, with all four valine codons in the decoding site of the 30S ribosomal, subunit. An intramolecular hydrogen bond involving the modification helps, to prestructure the anticodon loop. We found unusual base pairs with the, three noncomplementary codon bases, including a G.U base pair in standard, Watson-Crick geometry, which presumably involves an enol form for the, uridine. These structures suggest how a modification in the uridine at the, wobble position can expand the decoding capability of a tRNA.
About this StructureAbout this Structure
2UU9 is a Protein complex structure of sequences from Thermus thermophilus with PAR, MG, ZN and K as ligands. Full crystallographic information is available from OCA.
ReferenceReference
Mechanism for expanding the decoding capacity of transfer RNAs by modification of uridines., Weixlbaumer A, Murphy FV 4th, Dziergowska A, Malkiewicz A, Vendeix FA, Agris PF, Ramakrishnan V, Nat Struct Mol Biol. 2007 Jun;14(6):498-502. Epub 2007 May 13. PMID:17496902
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