1G0B

CARBONMONOXY LIGANDED EQUINE HEMOGLOBIN PH 8.5


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Work: 0.178 
  • R-Value Observed: 0.178 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Re-refinement Note

This entry reflects an alternative modeling of the original data in: 

  • 2MHB

Literature

Interface sliding as illustrated by the multiple quaternary structures of liganded hemoglobin.

Mueser, T.C.Rogers, P.H.Arnone, A.

(2000) Biochemistry 39: 15353-15364

  • DOI: 10.1021/bi0012944
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Initial crystallographic studies suggested that fully liganded mammalian hemoglobin can adopt only a single quaternary structure, the quaternary R structure. However, more recent crystallographic studies revealed the existence of a second quaternary ...

    Initial crystallographic studies suggested that fully liganded mammalian hemoglobin can adopt only a single quaternary structure, the quaternary R structure. However, more recent crystallographic studies revealed the existence of a second quaternary structure for liganded hemoglobin, the quaternary R2 structure. Since these quaternary structures can be crystallized, both must be energetically accessible structures that coexist in solution. Unanswered questions include (i) the relative abundance of the R and R2 structures under various solution conditions and (ii) whether other quaternary structures are energetically accessible for the liganded alpha(2)beta(2) hemoglobin tetramer. Although crystallographic methods cannot directly answer the first question, they represent the most direct and most accurate approach to answering the second question. We now have determined and refined three different crystal structures of bovine carbonmonoxyhemoglobin. These structures provide clear evidence that the dimer-dimer interface of liganded hemoglobin has a wide range of energetically accessible structures that are related to each other by a simple sliding motion. The dimer-dimer interface acts as a "molecular slide bearing" that allows the two alpha beta dimers to slide back and forth without greatly altering the number or the nature of the intersubunit contacts. Since the general stereochemical features of this interface are not unusual, it is likely that interface sliding of the kind displayed by fully liganded hemoglobin plays important structural and functional roles in many other protein assemblies.


    Related Citations: 
    • The structure of horse methaemoglobin at 2-0 A resolution.
      Ladner, R.C., Heidner, E.J., Perutz, M.F.
      (1977) J Mol Biol 114: 385

    Organizational Affiliation

    Department of Biochemistry, College of Medicine, The University of Iowa, Iowa City, Iowa 52242, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
HEMOGLOBIN ALPHA CHAIN
A
141Equus caballusMutation(s): 0 
Gene Names: HBA
Find proteins for P01958 (Equus caballus)
Go to UniProtKB:  P01958

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
HEMOGLOBIN BETA CHAIN
B
146Equus caballusMutation(s): 0 
Gene Names: HBB
Find proteins for P02062 (Equus caballus)
Go to UniProtKB:  P02062
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM

Download CCD File 
A, B
PROTOPORPHYRIN IX CONTAINING FE
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
CMO
Query on CMO

Download CCD File 
A, B
CARBON MONOXIDE
C O
UGFAIRIUMAVXCW-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Work: 0.178 
  • R-Value Observed: 0.178 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 108.8α = 90
b = 63.2β = 110.7
c = 54.6γ = 90
Software Package:
Software NamePurpose
MERLOTphasing
PROLSQrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-12-27
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2011-08-10
    Changes: Other