Experimental Data Snapshot

  • Resolution: 2.6 Å
  • R-Value Work: 0.161 

wwPDB Validation 3D Report Full Report

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Structure of trypanothione reductase from Crithidia fasciculata at 2.6 A resolution; enzyme-NADP interactions at 2.8 A resolution.

Bailey, S.Fairlamb, A.H.Hunter, W.N.

(1994) Acta Crystallogr.,Sect.D 50: 139-154

  • DOI: 10.1107/S0907444993011898

  • PubMed Abstract: 
  • Trypanothione reductase is an FAD-dependent disulfide oxidoreductase which catalyses the reduction of trypanothione using NADPH as co-factor. The enzyme is unique to protozoan parasites from the genera Trypanosoma and Leishmania and is an important t ...

    Trypanothione reductase is an FAD-dependent disulfide oxidoreductase which catalyses the reduction of trypanothione using NADPH as co-factor. The enzyme is unique to protozoan parasites from the genera Trypanosoma and Leishmania and is an important target for the design of improved antitrypanocidal drugs. We present details of the structure of trypanothione reductase from Crithidia fasciculata solved by molecular replacement, using human glutathione reductase as a search model, and refined to an R factor of 16.1% with data between 8.0 and 2.6 A resolution. The model comprises two subunits (one containing 487 residues, the other 486), an FAD prosthetic group, plus 392 solvent molecules. The last four C-terminal residues are not seen in either subunit and the density is poor for the N-terminal residue of subunit B. The model has a root-mean-square deviation from ideality of 0.016 A for bond lengths and 3.2 degrees for bond angles. Each subunit was independently refined in the latter stages of the analysis but the subunits remain similar as indicated by the root-mean-square deviation of 0.35 A for C(alpha) atoms. Trypanothione reductase has 36% sequence identity with human glutathione reductase and the root-mean-square deviation between the 462 C(alpha) atoms in the secondary structural units common to the two proteins is 1.1 A. However, there are large differences in the loop regions and significant shifts in the orientation of the four domains within each subunit. Domain II, which binds the dinucleotide co-factor, and domain IV, which forms the interface between the two subunits, are both rotated by approximately 5 degrees with respect to domain I, which binds the FAD moiety, when compared with glutathione reductase. Crystals of trypanothione reductase have been soaked in the dinucleotide co-factor NADPH and N(1)-glutathionylspermidine disulfide substrate and the structure of the resulting complex determined at 2.8 A resolution. Strong density is observed for the adenosine end of the co-factor which forms many charged interactions with the protein though the density for the nicotinamide moiety is more diffuse. The mode of binding indicates that NADP is bound to the enzyme in a similar conformation to that observed with human glutathione reductase.

    Related Citations: 
    • Molecular Characterization of the Trypanothione Reductase Gene from Crithidia Fasciculata and Trypanosoma Brucei: Comparison with Other Flavo Protein Disulphide Oxidoreductases with Respect to Substrate Specificity and Catalytic Mechanism
      Aboagye-Kwarteng, T.,Smith, K.,Fairlamb, A.H.
      (1992) Mol.Microbiol. 6: 3039
    • Active Site of Trypanothione Reductase: A Target for Rational Drug Design
      Hunter, W.N.,Bailey, S.,Habash, J.,Harrop, S.J.,Helliwell, J.R.,Aboagye-Kwarteng, T.,Smith, K.,Fairlamb, A.H.
      (1992) J.Mol.Biol. 227: 322
    • Substrate Interactions between Trypanothione Reductase and N1-Glutathionyldisulphide at 2.8 Angstroms Resolution
      Bailey, S.,Smith, K.,Fairlamb, A.H.,Hunter, W.N.
      (1993) Eur.J.Biochem. 213: 67
    • Initiating a Crystallographic Study of Trypanothione Reductase
      Hunter, W.N.,Smith, K.,Derewenda, Z.,Harrop, S.J.,Habash, J.,Islam, M.S.,Helliwell, J.R.,Fairlamb, A.H.
      (1990) J.Mol.Biol. 216: 235

    Organizational Affiliation

    Department of Chemistry, University of Manchester, England.


Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
A, B
487Crithidia fasciculataMutation(s): 0 
Gene Names: TPR
Find proteins for P39040 (Crithidia fasciculata)
Go to Gene View: TPR
Go to UniProtKB:  P39040
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
Query on FAD

Download SDF File 
Download CCD File 
A, B
C27 H33 N9 O15 P2
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Resolution: 2.6 Å
  • R-Value Work: 0.161 
  • Space Group: P 41
Unit Cell:
Length (Å)Angle (°)
a = 128.800α = 90.00
b = 128.800β = 90.00
c = 92.500γ = 90.00
Software Package:
Software NamePurpose
X-PLORmodel building

Structure Validation

View Full Validation Report or Ramachandran Plots

Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1994-07-31
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance