1GZX

oxy T state haemoglobin: oxygen bound at all four haems


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.195 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Crystal Structure of T State Haemoglobin with Oxygen Bound at All Four Haems.

Paoli, M.Liddington, R.Tame, J.Wilkinson, A.Dodson, G.

(1996) J Mol Biol 256: 775

  • DOI: 10.1006/jmbi.1996.0124
  • Primary Citation of Related Structures:  
    1GZX

  • PubMed Abstract: 
  • The cooperative binding of oxygen by haemoglobin results from restraints on ligand binding in the T state. The unfavourable interactions made by the ligands at the haems destabilise the T state and favour the high affinity R state. The T <==> R equilibrium leads, in the presence of a ligand, to a rapid increase in the R state population and therefore generates cooperative binding ...

    The cooperative binding of oxygen by haemoglobin results from restraints on ligand binding in the T state. The unfavourable interactions made by the ligands at the haems destabilise the T state and favour the high affinity R state. The T <==> R equilibrium leads, in the presence of a ligand, to a rapid increase in the R state population and therefore generates cooperative binding. There is now considerable understanding of this phenomenon, but the interactions that reduce ligand affinity in the T state have not yet been fully explored, owing to the difficulties in preparing T state haemoglobin crystals in which all the subunits are oxygenated. A protocol has been developed to oxygenate deoxy T state adult human haemoglobin (HbA) crystals in air at 4 C at all four haems without significant loss of crystalline order. The X-ray crystal structure, determined to 2.1 A spacing, shows significant changes in the alpha and beta haem pockets as well as changes at the alpha(1)beta(2) interface in the direction of the R quaternary structure. Most of the shifts and deviations from deoxy T state HbA are similar to, but larger than, those previously observed in the T state met and other partially liganded T state forms. They provide clear evidence of haem-haem interaction in the T state.


    Organizational Affiliation

    Department of Chemistry, University of York, Heslington, York, UK.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
HEMOGLOBIN ALPHA CHAINA, C141Homo sapiensMutation(s): 0 
Gene Names: HBA1HBA2
UniProt & NIH Common Fund Data Resources
Find proteins for P69905 (Homo sapiens)
Explore P69905 
Go to UniProtKB:  P69905
PHAROS:  P69905
Protein Feature View
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  • Reference Sequence
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Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
HEMOGLOBIN BETA CHAINB, D146Homo sapiensMutation(s): 0 
Gene Names: HBB
UniProt & NIH Common Fund Data Resources
Find proteins for P68871 (Homo sapiens)
Explore P68871 
Go to UniProtKB:  P68871
PHAROS:  P68871
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.199 
  • R-Value Observed: 0.195 
  • Space Group: P 21 21 2 A
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 97.05α = 90
b = 99.5β = 90
c = 66.11γ = 90
Software Package:
Software NamePurpose
PROLSQrefinement
MOSFLMdata reduction
ROTAVATAdata scaling
PROLSQphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2002-07-08
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2019-05-22
    Changes: Data collection, Other, Refinement description