3FOC

Tryptophanyl-tRNA synthetase from Giardia lamblia


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.09 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.200 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

The structure of tryptophanyl-tRNA synthetase from Giardia lamblia reveals divergence from eukaryotic homologs.

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.

(2010) J Struct Biol 171: 238-243

  • DOI: https://doi.org/10.1016/j.jsb.2010.04.010
  • Primary Citation of Related Structures:  
    3FOC

  • 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.


  • Organizational Affiliation

    Medical Structural Genomics of Pathogenic Protozoa, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Tryptophanyl-tRNA synthetase
A, B
451Giardia lamblia ATCC 50803Mutation(s): 0 
Gene Names: GL50803_3032
EC: 6.1.1.2
UniProt
Find proteins for A8B8N3 (Giardia intestinalis (strain ATCC 50803 / WB clone C6))
Explore A8B8N3 
Go to UniProtKB:  A8B8N3
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA8B8N3
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.09 Å
  • R-Value Free: 0.234 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.200 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 106.714α = 90
b = 140.147β = 90
c = 90.352γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
MOLREPphasing
REFMACrefinement
PDB_EXTRACTdata extraction
ADSCdata collection

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2009-01-13
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Version format compliance
  • Version 1.2: 2017-11-01
    Changes: Refinement description
  • Version 1.3: 2023-09-06
    Changes: Data collection, Database references, Derived calculations, Refinement description