Download MendeleyClass I Tyrosyl-tRNA Synthetase Has a Class II Mode or tRNA Recognition
Yaremchuk, A., Kriklivyi, I., Tukalo, M., Cusack, S.(2002) EMBO J 21: 3829
- PubMed: 12110594
- DOI: https://doi.org/10.1093/emboj/cdf373
- Primary Citation of Related Structures:
1H3E, 1H3F - PubMed Abstract:
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.
Organizational Affiliation:
European Molecular Biology Laboratory, Grenoble Outstation, c/o ILL, 156X, F-38042 Grenoble cedex 9, France.
