3FOC
Tryptophanyl-tRNA synthetase from Giardia lamblia
Summary for 3FOC
| Entry DOI | 10.2210/pdb3foc/pdb |
| Descriptor | Tryptophanyl-tRNA synthetase, GLYCEROL, SULFATE ION, ... (4 entities in total) |
| Functional Keywords | structural genomics, tryptophanyl-trna synthetase, giardiasis, aminoacyl-trna synthetase, ligase, medical structural genomics of pathogenic protozoa, msgpp |
| Biological source | Giardia lamblia ATCC 50803 |
| Total number of polymer chains | 2 |
| Total formula weight | 101727.67 |
| Authors | Arakaki, T.L.,Merritt, E.A.,Medical Structural Genomics of Pathogenic Protozoa (MSGPP) (deposition date: 2008-12-29, release date: 2009-01-13, Last modification date: 2023-09-06) |
| Primary citation | Arakaki, T.L.,Carter, M.,Napuli, A.J.,Verlinde, C.L.,Fan, E.,Zucker, F.,Buckner, F.S.,Van Voorhis, W.C.,Hol, W.G.,Merritt, E.A. The structure of tryptophanyl-tRNA synthetase from Giardia lamblia reveals divergence from eukaryotic homologs. J.Struct.Biol., 171:238-243, 2010 Cited by PubMed Abstract: The 2.1A crystal structure of tryptophanyl-tRNA synthetase (TrpRS) from the diplomonad Giardia lamblia reveals that the N-terminus of this class I aminoacyl-tRNA synthetase forms a 16-residue alpha-helix. This helix replaces a beta-hairpin that is required by human TrpRS for normal activity and has been inferred to play a similar role in all eukaryotic TrpRS. The primary sequences of TrpRS homologs from several basal eukaryotes including Giardia lack a set of three residues observed to stabilize interactions with this beta-hairpin in the human TrpRS. Thus the present structure suggests that the activation reaction mechanism of TrpRS from the basal eukaryote G. lamblia differs from that of higher eukaryotes. Furthermore, the protein as observed in the crystal forms an (alpha(2))(2) homotetramer. The canonical dimer interface observed in all previous structures of tryptophanyl-tRNA synthetases is maintained, but in addition each N-terminal alpha-helix reciprocally interlocks with the equivalent helix from a second dimer to form a dimer of dimers. Although we have no evidence for tetramer formation in vivo, modeling indicates that the crystallographically observed tetrameric structure would be compatible with the tRNA binding mode used by dimeric TrpRS and TyrRS. PubMed: 20438846DOI: 10.1016/j.jsb.2010.04.010 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.09 Å) |
Structure validation
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