1ZCR

Crystal structure of human Transthyretin with bound iodide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.203 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The effect of iodide and chloride on transthyretin structure and stability

Hornberg, A.Hultdin, U.W.Olofsson, A.Sauer-Eriksson, A.E.

(2005) Biochemistry 44: 9290-9299

  • DOI: 10.1021/bi050249z
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Transthyretin amyloid formation occurs through a process of tetramer destabilization and partial unfolding. Small molecules, including the natural ligand thyroxine, stabilize the tetrameric form of the protein, and serve as inhibitors of amyloid form ...

    Transthyretin amyloid formation occurs through a process of tetramer destabilization and partial unfolding. Small molecules, including the natural ligand thyroxine, stabilize the tetrameric form of the protein, and serve as inhibitors of amyloid formation. Crucial for TTR's ligand-binding properties are its three halogen-binding sites situated at the hormone-binding channel. In this study, we have performed a structural characterization of the binding of two halides, iodide and chloride, to TTR. Chlorides are known to shield charge repulsions at the tetrameric interface of TTR, which improve tetramer stability of the protein. Our study shows that iodides, like chlorides, provide tetramer stabilization in a concentration-dependent manner and at concentrations approximately 15-fold below that of chlorides. To elucidate binding sites of the halides, we took advantage of the anomalous scattering of iodide and used the single-wavelength anomalous dispersion (SAD) method to solve the iodide-bound TTR structure at 1.8 A resolution. The structure of chloride-bound TTR was determined at 1.9 A resolution using difference Fourier techniques. The refined structures showed iodides and chlorides bound at two of the three halogen-binding sites located at the hydrophobic channel. These sites therefore also function as halide-binding sites.


    Organizational Affiliation

    Umeå Centre for Molecular Pathogenesis, Umeå University, SE-901 87 Umeå, Sweden.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Transthyretin
A, B
128Homo sapiensGene Names: TTR (PALB)
Find proteins for P02766 (Homo sapiens)
Go to Gene View: TTR
Go to UniProtKB:  P02766
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
IOD
Query on IOD

Download SDF File 
Download CCD File 
A, B
IODIDE ION
I
XMBWDFGMSWQBCA-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.203 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 43.380α = 90.00
b = 86.260β = 90.00
c = 64.440γ = 90.00
Software Package:
Software NamePurpose
CNSphasing
REFMACrefinement
SCALEPACKdata scaling
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-07-12
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Advisory, Derived calculations, Version format compliance