1h3f
TYROSYL-TRNA SYNTHETASE FROM THERMUS THERMOPHILUS COMPLEXED WITH TYROSINOL
OverviewOverview
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.
About this StructureAbout this Structure
1H3F is a Single protein structure of sequence from Thermus thermophilus. Full crystallographic information is available from OCA.
ReferenceReference
Class I tyrosyl-tRNA synthetase has a class II mode of cognate tRNA recognition., Yaremchuk A, Kriklivyi I, Tukalo M, Cusack S, EMBO J. 2002 Jul 15;21(14):3829-40. PMID:12110594 Page seeded by OCA on Fri May 2 18:23:07 2008