2R1H

met-Trout IV hemoglobin at pH 6.3


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.170 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural analysis of fish versus mammalian hemoglobins: Effect of the heme pocket environment on autooxidation and hemin loss.

Aranda, R.Cai, H.Worley, C.E.Levin, E.J.Li, R.Olson, J.S.Phillips Jr., G.N.Richards, M.P.

(2008) Proteins 75: 217-230

  • DOI: 10.1002/prot.22236
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The underlying stereochemical mechanisms for the dramatic differences in autooxidation and hemin loss rates of fish versus mammalian hemoglobins (Hb) have been examined by determining the crystal structures of perch, trout IV, and bovine Hb at high a ...

    The underlying stereochemical mechanisms for the dramatic differences in autooxidation and hemin loss rates of fish versus mammalian hemoglobins (Hb) have been examined by determining the crystal structures of perch, trout IV, and bovine Hb at high and low pH. The fish Hbs autooxidize and release hemin approximately 50- to 100-fold more rapidly than bovine Hb. Five specific amino acid replacements in the CD corner and along the E helix appear to cause the increased susceptibility of fish Hbs to oxidative degradation compared with mammalian Hbs. Ile is present at the E11 helical position in most fish Hb chains whereas a smaller Val residue is present in all mammalian alpha and beta chains. The larger IleE11 side chain sterically hinders bound O(2) and facilitates dissociation of the neutral superoxide radical, enhancing autooxidation. Lys(E10) is found in most mammalian Hb and forms favorable electrostatic and hydrogen bonding interactions with the heme-7-propionate. In contrast, Thr(E10) is present in most fish Hbs and is too short to stabilize bound heme, and causes increased rates of hemin dissociation. Especially high rates of hemin loss in perch Hb are also due to a lack of electrostatic interaction between His(CE3) and the heme-6 propionate in alpha subunits whereas this interaction does occur in trout IV and bovine Hb. There is also a larger gap for solvent entry into the heme crevice near beta CD3 in the perch Hb (approximately 8 A) compared with trout IV Hb (approximately 6 A) which in turn is significantly higher than that in bovine Hb (approximately 4 A) at low pH. The amino acids at CD4 and E14 differ between bovine and the fish Hbs and have the potential to modulate oxidative degradation by altering the orientation of the distal histidine and the stability of the E-helix. Generally rapid rates of lipid oxidation in fish muscle can be partly attributed to the fact that fish Hbs are highly susceptible to oxidative degradation.


    Organizational Affiliation

    Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Hemoglobin subunit alpha-4
A, C
143Oncorhynchus mykissMutation(s): 0 
Gene Names: hba4
Find proteins for P14527 (Oncorhynchus mykiss)
Go to UniProtKB:  P14527
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Hemoglobin subunit beta-4
B, D
147Oncorhynchus mykissMutation(s): 0 
Gene Names: hbb4
Find proteins for P02141 (Oncorhynchus mykiss)
Go to UniProtKB:  P02141
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDO
Query on EDO

Download SDF File 
Download CCD File 
B, C, D
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
HEM
Query on HEM

Download SDF File 
Download CCD File 
A, B, C, D
PROTOPORPHYRIN IX CONTAINING FE
HEME
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
ACE
Query on ACE
A, C
NON-POLYMERC2 H4 O

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.170 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 57.063α = 90.00
b = 62.998β = 92.20
c = 77.016γ = 90.00
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
HKL-2000data reduction
SCALEPACKdata scaling
HKL-2000data collection
MOLREPphasing
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-09-02
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance
  • Version 1.2: 2013-01-30
    Type: Database references, Structure summary