3M9J

Crystal structure of human thioredoxin C69/73S double mutant, reduced form


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.1 Å
  • R-Value Free: 0.172 
  • R-Value Work: 0.144 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of human thioredoxin revealing an unraveled helix and exposed S-nitrosation site.

Weichsel, A.Kem, M.Montfort, W.R.

(2010) Protein Sci. 19: 1801-1806

  • DOI: 10.1002/pro.455
  • Primary Citation of Related Structures:  
  • Also Cited By: 4OO5, 4OO4

  • PubMed Abstract: 
  • Thioredoxins reduce disulfide bonds and other thiol modifications in all cells using a CXXC motif. Human thioredoxin 1 is unusual in that it codes for an additional three cysteines in its 105 amino acid sequence, each of which have been implicated in ...

    Thioredoxins reduce disulfide bonds and other thiol modifications in all cells using a CXXC motif. Human thioredoxin 1 is unusual in that it codes for an additional three cysteines in its 105 amino acid sequence, each of which have been implicated in other reductive activities. Cys 62 and Cys 69 are buried in the protein interior and lie at either end of a short helix (helix 3), and yet can disulfide link under oxidizing conditions. Cys 62 is readily S-nitrosated, giving rise to a SNO modification, which is also buried. Here, we present two crystal structures of the C69S/C73S mutant protein under oxidizing (1.5 A) and reducing (1.1 A) conditions. In the oxidized structure, helix 3 is unraveled and displays a new conformation that is stabilized by a series of new hydrogen bonds and a disulfide link with Cys 62 in a neighboring molecule. The new conformation provides an explanation for how a completely buried residue can participate in SNO exchange reactions.


    Related Citations: 
    • Crystal structures of reduced, oxidized, and mutated human thioredoxins: evidence for a regulatory homodimer.
      Weichsel, A.,Gasdaska, J.R.,Powis, G.,Montfort, W.R.
      (1996) Structure 4: 735
    • Buried S-nitrosocysteine revealed in crystal structures of human thioredoxin.
      Weichsel, A.,Brailey, J.L.,Montfort, W.R.
      (2007) Biochemistry 46: 1219


    Organizational Affiliation

    Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Thioredoxin
A, B
105Homo sapiensMutation(s): 2 
Gene Names: TXN (TRDX, TRX, TRX1)
Find proteins for P10599 (Homo sapiens)
Go to Gene View: TXN
Go to UniProtKB:  P10599
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.1 Å
  • R-Value Free: 0.172 
  • R-Value Work: 0.144 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 37.233α = 90.00
b = 46.207β = 93.25
c = 52.330γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data reduction
MOLREPphasing
XDSdata scaling
REFMACrefinement
DENZOdata reduction
PDB_EXTRACTdata extraction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-08-11
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2017-11-08
    Type: Refinement description