3FOC

Tryptophanyl-tRNA synthetase from Giardia lamblia

3FOC の概要

• エントリーDOI: 10.2210/pdb3foc/pdb
• 分子名称: Tryptophanyl-tRNA synthetase, GLYCEROL, SULFATE ION, ... (4 entities in total)
• 機能のキーワード: structural genomics, tryptophanyl-trna synthetase, giardiasis, aminoacyl-trna synthetase, ligase, medical structural genomics of pathogenic protozoa, msgpp
• 由来する生物種: Giardia lamblia ATCC 50803
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 101727.67

構造登録者

Arakaki, T.L.,Merritt, E.A.,Medical Structural Genomics of Pathogenic Protozoa (MSGPP) (登録日: 2008-12-29, 公開日: 2009-01-13, 最終更新日: 2023-09-06)

主引用文献

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

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: 20438846
DOI: 10.1016/j.jsb.2010.04.010

実験手法

X-RAY DIFFRACTION (2.09 Å)