2ROX

TRANSTHYRETIN (ALSO CALLED PREALBUMIN) COMPLEX WITH THYROXINE (T4)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.170 

wwPDB Validation   3D Report Full Report


This is version 2.0 of the entry. See complete history


Literature

Structures of human transthyretin complexed with thyroxine at 2.0 A resolution and 3',5'-dinitro-N-acetyl-L-thyronine at 2.2 A resolution.

Wojtczak, A.Cody, V.Luft, J.R.Pangborn, W.

(1996) Acta Crystallogr D Biol Crystallogr 52: 758-765

  • DOI: https://doi.org/10.1107/S0907444996003046
  • Primary Citation of Related Structures:  
    2ROX, 2ROY

  • PubMed Abstract: 

    The molecular structures of two human transthyretin (hTTR, prealbumin) complexes, co-crystallized with thyroxine (3,5,3',5'-tetraiodo-L-thyronine; T(4)), and with 3',5'-dinitro-N-acetyl-LL-thyronine (DNNAT), were determined by X-ray diffraction methods. Crystals of both structures are orthorhombic, space group P2(1)2(1)2, and have two independent monomers in the asymmetric unit of the crystal lattice. These structures have been refined to 17.0% for 8-2.0 A resolution data for the T(4) complex (I), and to R = 18.4% for 8-2.2 A resolution data for the DNNAT structure (II). This report provides a detailed description of T(4) binding to wild-type hTTR at 2.0 A resolution, as well as DNNAT. In both structures, the two independent hormone-binding sites of the TTR tetramer are occupied by ligand. A 50% statistical disorder model was applied to account for the crystallographic twofold symmetry along the binding channel and the lack of such symmetry for the ligands. Results for the co-crystallized T(4) complex show that T(4) binds deep in the hormone-binding channel and displaces the bound water previously reported for T(4) soaked into a native transthyretin crystal [Blake & Oatley (1977). Nature (London), 268, 115-120]. DNNAT also binds deeper in the channel toward the tetramer center than T(4) with the nitro groups occupying the symmetrical innermost halogen pockets. The N-acetyl moiety does not form polar contacts with the protein side chains as it is oriented toward the center of the channel. The weak binding affinity of DNNAT results from the loss of hydrophobic interactions with the halogen binding pockets as observed in T(4) binding. These data suggest that the halogen-binding sites toward the tetramer center are of primary importance as they are occupied by analogues with weak affinity to TTR, and are therefore selected over the other halogen sites which contribute more strongly to the overall binding affinity.


  • Organizational Affiliation

    Hauptman-Woodward Medical Research Institute, Inc., Buffalo, NY 14203, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
TRANSTHYRETIN
A, B
127Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for P02766 (Homo sapiens)
Explore P02766 
Go to UniProtKB:  P02766
PHAROS:  P02766
GTEx:  ENSG00000118271 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP02766
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
T44 PDBBind:  2ROX IC50: 1.05e+4 (nM) from 1 assay(s)
BindingDB:  2ROX IC50: min: 2188, max: 1.05e+4 (nM) from 3 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Work: 0.170 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 43.41α = 90
b = 85.992β = 90
c = 65.552γ = 90
Software Package:
Software NamePurpose
PROLSQrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1997-04-21
    Type: Initial release
  • Version 1.1: 2008-03-25
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 2.0: 2023-11-15
    Changes: Atomic model, Data collection, Database references, Derived calculations, Other