1h3f: Difference between revisions

Bacterial tyrosyl-tRNA synthetases (TyrRS) possess a flexibly linked, C-terminal domain of approximately 80 residues, which has hitherto been, disordered in crystal structures of the enzyme. We have determined the, structure of Thermus thermophilus TyrRS at 2.0 A resolution in a crystal, form in which the C-terminal domain is ordered, and confirm that the fold, is similar to part of the C-terminal domain of ribosomal protein S4. We, have also determined the structure at 2.9 A resolution of the complex of, T.thermophilus TyrRS with cognate tRNA(tyr)(G Psi A). In this structure, the C-terminal domain binds between the characteristic long variable arm, of the tRNA and the anti-codon stem, thus recognizing the unique shape of, the tRNA. The anticodon bases have a novel conformation with A-36 stacked, on G-34, and both G-34 and Psi-35 are base-specifically recognized. The, tRNA binds across the two subunits of the dimeric enzyme and, remarkably, the mode of recognition of the class I TyrRS for its cognate tRNA, resembles that of a class II synthetase in being from the major groove, side of the acceptor stem.

1H3F is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with SO4 and TYB as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1H3F OCA].  

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