Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 11829.38 
• Atom Count: 976 
• Residue Count: 105 
• Unique protein chains: 1

2HSH

Crystal structure of C73S mutant of human thioredoxin-1 oxidized with H2O2

• DOI: 10.2210/pdb2HSH/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): 1 


• Deposited: 2006-07-21 Released: 2006-12-05 
• Deposition Author(s): Weichsel, A., Montfort, W.R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.35 Å
• R-Value Free: 0.168 
• R-Value Work: 0.123 

Literature

Buried s-nitrosocysteine revealed in crystal structures of human thioredoxin.

Weichsel, A., Brailey, J.L., Montfort, W.R.

(2007) Biochemistry 46: 1219-1227

• PubMed: 17260951 
• DOI: 10.1021/bi061878r
• Primary Citation of Related Structures:  
  2IIY, 2IFQ, 2HXK
• Also Cited By: 3M9K, 3M9J


• PubMed Abstract: 
  

We have determined the 1.65 A crystal structure of human thioredoxin-1 after treatment with S-nitrosoglutathione, providing a high-resolution view of this important protein modification and mechanistic insight into protein transnitrosation. Thioredoxin-1 appears to play an intermediary role in cellular S-nitrosylation and is important in numerous biological and pathobiological activities. S-Nitroso modifications of cysteines 62 and 69 are clearly visible in the structure and display planar cis geometries, whereas cysteines 32, 35, and 73 form intra- and intermolecular disulfide bonds. Surprisingly, the Cys 62 nitroso group is completely buried and pointing to the protein interior yet is the most readily formed at neutral pH. The Cys 69 nitroso group is also protected but requires a higher pH for stable formation. The helix intervening between residues 62 and 69 shifts by approximately 0.5 A to accommodate the SNO groups. The crystallographic asymmetric unit contains three independent molecules of thioredoxin, providing three views of the nitrosated protein. The three molecules are in general agreement but display subtle differences, including both cis and trans conformers for Cys 69 SNO in molecule C, and greater disorder in the Cys 62-Cys 69 helix in molecule B. Possible mechanisms for protein transnitrosation with specific geometric requirements and charge stabilization of the nitroxyl disulfide reaction intermediate are discussed.

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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.
  (2006) Structure 4: 735




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Organizational Affiliation: 

Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, Arizona 85721, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Thioredoxin	A	105	Homo sapiens	Mutation(s): 1  Gene Names: TXN (TRDX, TRX, TRX1)
Find proteins for P10599 (Homo sapiens) Go to Gene View: TXN Go to UniProtKB:  P10599

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
PO4	A	PHOSPHATE ION O4 P NBIIXXVUZAFLBC-UHFFFAOYSA-K

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.35 Å
• R-Value Free: 0.168 
• R-Value Work: 0.123 
• Space Group: C 1 2 1

Unit Cell:

Length (Å)	Angle (°)
a = 66.166	α = 90.00
b = 26.375	β = 95.47
c = 51.100	γ = 90.00

Software Package:

Software Name	Purpose
REFMAC	refinement
CrystalClear	data scaling
CrystalClear	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-07-21 
• Released Date: 2006-12-05 
• Deposition Author(s): Weichsel, A., Montfort, W.R.

Revision History 

• Version 1.0: 2006-12-05
  Type: Initial release
• Version 1.1: 2008-05-01
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance