1O85

Radiation-reduced Tryparedoxin-I


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.195 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Tryparedoxins from Crithidia Fasciculata and Trypanosoma Brucei: Photoreduction of the Redox Disulfide Using Synchrotron Radiation and Evidence for a Conformational Switch Implicated in Function

Alphey, M.S.Gabrielsen, M.Micossi, E.Leonard, G.Mcsweeney, S.M.Ravelli, R.B.G.Tetaud, E.Fairlamb, A.H.Bond, C.S.Hunter, W.N.

(2003) J.Biol.Chem. 278: 25919

  • DOI: 10.1074/jbc.M301526200
  • Primary Citation of Related Structures:  1O73, 1O7U, 1O8W, 1O8X, 1OC8, 1OC9

  • PubMed Abstract: 
  • Tryparedoxin (TryX) is a member of the thioredoxin (TrX) fold family involved in the regulation of oxidative stress in parasitic trypanosomatids. Like TrX, TryX carries a characteristic Trp-Cys-Xaa-Xaa-Cys motif, which positions a redox-active disulf ...

    Tryparedoxin (TryX) is a member of the thioredoxin (TrX) fold family involved in the regulation of oxidative stress in parasitic trypanosomatids. Like TrX, TryX carries a characteristic Trp-Cys-Xaa-Xaa-Cys motif, which positions a redox-active disulfide underneath a tryptophan lid. We report the structure of a Crithidia fasciculata tryparedoxin isoform (CfTryX2) in two crystal forms and compare them with structures determined previously. Efforts to chemically generate crystals of reduced TryX1 were unsuccessful, and we carried out a novel experiment to break the redox-active disulfide, formed between Cys-40 and Cys-43, utilizing the intense x-radiation from a third generation synchrotron undulator beamline. A time course study of the S-S bond cleavage is reported with the structure of a TryX1 C43A mutant as the control. When freed from the constraints of a disulfide link to Cys-43, Cys-40 pivots to become slightly more solvent-accessible. In addition, we have determined the structure of Trypanosoma brucei TryX, which, influenced by the molecular packing in the crystal lattice, displays a significantly different orientation of the active site tryptophan lid. This structural change may be of functional significance when TryX interacts with tryparedoxin peroxidase, the final protein in the trypanothione-dependent peroxidase pathway. Comparisons with chloroplast TrX and its substrate fructose 1,6-bisphosphate phosphatase suggest that this movement may represent a general feature of redox regulation in the trypanothione and thioredoxin peroxidase pathways.


    Related Citations: 
    • The High Resolution Crystal Structure of Recombinant Crithidia Fasciculata Tryparedoxin-I
      Alphey, M.S.,Leonard, G.,Gourley, D.G.,Tetaud, E.,Fairlamb, A.H.,Hunter, W.N.
      (1999) J.Biol.Chem. 274: 25613


    Organizational Affiliation

    Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TRYPAREDOXIN
A
146Crithidia fasciculataGene Names: TryX (txnI)
Find proteins for O96438 (Crithidia fasciculata)
Go to UniProtKB:  O96438
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.195 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 38.060α = 90.00
b = 50.885β = 90.00
c = 70.703γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
REFMACrefinement
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-04-24
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance