Crystal Structure of the C-Ala domain from Aquifex aeolicus alanyl-tRNA synthetase

Experimental Data Snapshot

  • Resolution: 1.85 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.184 
  • R-Value Observed: 0.186 

wwPDB Validation   3D Report Full Report

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The C-Ala domain brings together editing and aminoacylation functions on one tRNA.

Guo, M.Chong, Y.E.Beebe, K.Shapiro, R.Yang, X.L.Schimmel, P.

(2009) Science 325: 744-747

  • DOI: https://doi.org/10.1126/science.1174343
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Protein synthesis involves the accurate attachment of amino acids to their matching transfer RNA (tRNA) molecules. Mistranslating the amino acids serine or glycine for alanine is prevented by the function of independent but collaborative aminoacylation and editing domains of alanyl-tRNA synthetases (AlaRSs). We show that the C-Ala domain plays a key role in AlaRS function. The C-Ala domain is universally tethered to the editing domain both in AlaRS and in many homologous free-standing editing proteins. Crystal structure and functional analyses showed that C-Ala forms an ancient single-stranded nucleic acid binding motif that promotes cooperative binding of both aminoacylation and editing domains to tRNA(Ala). In addition, C-Ala may have played an essential role in the evolution of AlaRSs by coupling aminoacylation to editing to prevent mistranslation.

  • Organizational Affiliation

    The Skaggs Institute for Chemical Biology and the Department of Molecular Biology, The Scripps Research Institute, BCC-379, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Alanyl-tRNA synthetase
A, B
111Aquifex aeolicusMutation(s): 0 
Gene Names: alaS
Find proteins for O67323 (Aquifex aeolicus (strain VF5))
Explore O67323 
Go to UniProtKB:  O67323
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO67323
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 1.85 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.184 
  • R-Value Observed: 0.186 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 50.74α = 90
b = 54.506β = 90
c = 66.256γ = 90
Software Package:
Software NamePurpose
Blu-Icedata collection
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2009-10-06
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2024-02-21
    Changes: Data collection, Database references