2ZLU

Horse methemoglobin high salt, pH 7.0 (88% relative humidity)

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.193 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history. 

Literature

Water-mediated variability in the structure of relaxed-state haemoglobin

Kaushal, P.S., Sankaranarayanan, R., Vijayan, M.

(2008) Acta Crystallogr.,Sect.F 64: 463-469

  • DOI: 10.1107/S1744309108013109
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    • The crystal structure of high-salt horse methaemoglobin has been determined at environmental relative humidities (r.h.) of 88, 79, 75 and 66%. The molecule is in the R state in the native and the r.h. 88% crystals. At r.h. 79%, the water content of t ...

    The crystal structure of high-salt horse methaemoglobin has been determined at environmental relative humidities (r.h.) of 88, 79, 75 and 66%. The molecule is in the R state in the native and the r.h. 88% crystals. At r.h. 79%, the water content of the crystal is reduced and the molecule appears to move towards the R2 state. The crystals undergo a water-mediated transformation involving a doubling of one of the unit-cell parameters and an increase in water content when the environmental humidity is further reduced to r.h. 75%. The water content is now similar to that in the native crystals and the molecules are in the R state. The crystal structure at r.h. 66% is similar, but not identical, to that at r.h. 75%, but the solvent content is substantially reduced and the molecules have a quaternary structure that is in between those corresponding to the R and R2 states. Thus, variation in hydration leads to variation in the quaternary structure. Furthermore, partial dehydration appears to shift the structure from the R state to the R2 state. This observation is in agreement with the earlier conclusion that the changes in protein structure that accompany partial dehydration are similar to those that occur during protein action.

    Related Citations: 
    • The structure of hemoglobin III: Direct determination of the molecular transform
      Perutz, M.F.
      (1954) Proc.R.Soc.Lond A Math.Phys.Sci. 225: 264
    • Structure of human methaemoglobin: The variation of a theme
      Biswal, B.K.,Vijayan, M.
      (2001) Curr.Sci. 81: 1100
    • Structures of human oxy- and deoxyhaemoglobin at different levels of humidity: variability in the T state
      Biswal, B.K.,Vijayan, M.
      (2002) Acta Crystallogr.,Sect.D 58: 1155
    • A new relaxed state in horse methemoglobin characterized by crystallographic studies
      Sankaranarayanan, R.,Biswal, B.K.,Vijayan, M.
      (2005) Proteins 60: 547
    • Discontinuous lattice changes in hemoglobin crystal
      Huxley, H.E.,Kendrew, J.C.
      (1953) Acta Crystallogr. 6: 76

    Organizational Affiliation: 

    Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Hemoglobin subunit alpha
A
141Equus caballusMutation(s): 0 
Gene Names: HBA
Find proteins for P01958 (Equus caballus)
Go to UniProtKB:  P01958
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Hemoglobin subunit beta
B
146Equus caballusMutation(s): 0 
Gene Names: HBB
Find proteins for P02062 (Equus caballus)
Go to Gene View: HBB
Go to UniProtKB:  P02062
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM
Download SDF File 
Download CCD File 
A, B
PROTOPORPHYRIN IX CONTAINING FE
HEME
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.193 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 108.184α = 90.00
b = 63.336β = 111.09
c = 54.409γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
REFMACrefinement
SCALEPACKdata scaling

Structure Validation

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View more in-depth experimental data

Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-06-24
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance