6HK2

Crystal structure of ferric R-state human methemoglobin bound to maleimide-deferoxamine bifunctional chelator (DFO)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.55 Å
  • R-Value Free: 0.212 
  • R-Value Work: 0.167 
  • R-Value Observed: 0.169 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.2 of the entry. See complete history


Literature

Biodistribution PET/CT Study of Hemoglobin-DFO-89Zr Complex in Healthy and Lung Tumor-Bearing Mice.

Kiraga, L.Cerutti, G.Braniewska, A.Strzemecki, D.Sas, Z.Boffi, A.Savino, C.Montemiglio, L.C.Turnham, D.Seaton, G.Bonamore, A.Clarkson, R.Dabkowski, A.M.Paisey, S.J.Taciak, B.Kucharzewska, P.Rygiel, T.P.Krol, M.

(2020) Int J Mol Sci 21

  • DOI: https://doi.org/10.3390/ijms21144991
  • Primary Citation of Related Structures:  
    6HK2

  • PubMed Abstract: 

    Proteins, as a major component of organisms, are considered the preferred biomaterials for drug delivery vehicles. Hemoglobin (Hb) has been recently rediscovered as a potential drug carrier, but its use for biomedical applications still lacks extensive investigation. To further explore the possibility of utilizing Hb as a potential tumor targeting drug carrier, we examined and compared the biodistribution of Hb in healthy and lung tumor-bearing mice, using for the first time 89 Zr labelled Hb in a positron emission tomography (PET) measurement. Hb displays a very high conjugation yield in its fast and selective reaction with the maleimide-deferoxamine (DFO) bifunctional chelator. The high-resolution X-ray structure of the Hb-DFO complex demonstrated that cysteine β93 is the sole attachment moiety to the αβ-protomer of Hb. The Hb-DFO complex shows quantitative uptake of 89 Zr in solution as determined by radiochromatography. Injection of 0.03 mg of Hb-DFO- 89 Zr complex in healthy mice indicates very high radioactivity in liver, followed by spleen and lungs, whereas a threefold increased dosage results in intensification of PET signal in kidneys and decreased signal in liver and spleen. No difference in biodistribution pattern is observed between naïve and tumor-bearing mice. Interestingly, the liver Hb uptake did not decrease upon clodronate-mediated macrophage depletion, indicating that other immune cells contribute to Hb clearance. This finding is of particular interest for rapidly developing clinical immunology and projects aiming to target, label or specifically deliver agents to immune cells.


  • Organizational Affiliation

    Department of Cancer Biology, Institute of Biology, Warsaw University of Life Sciences, 02-787 Warsaw, Poland.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Hemoglobin subunit alpha
A, C
141Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for P69905 (Homo sapiens)
Explore P69905 
Go to UniProtKB:  P69905
PHAROS:  P69905
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP69905
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Hemoglobin subunit beta
B, D
146Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for P68871 (Homo sapiens)
Explore P68871 
Go to UniProtKB:  P68871
PHAROS:  P68871
GTEx:  ENSG00000244734 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP68871
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM

Download Ideal Coordinates CCD File 
E [auth A],
H [auth B],
N [auth C],
Q [auth D]
PROTOPORPHYRIN IX CONTAINING FE
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
G7Z
Query on G7Z

Download Ideal Coordinates CCD File 
I [auth B],
R [auth D]
3-[2,5-bis(oxidanylidene)pyrrolidin-1-yl]-~{N}-methyl-propanamide
C8 H12 N2 O3
RCCJIJUHJOCJIV-UHFFFAOYSA-N
SO4
Query on SO4

Download Ideal Coordinates CCD File 
G [auth A]
J [auth B]
K [auth B]
L [auth B]
M [auth B]
G [auth A],
J [auth B],
K [auth B],
L [auth B],
M [auth B],
O [auth C],
P [auth C]
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
OXY
Query on OXY

Download Ideal Coordinates CCD File 
F [auth A]OXYGEN MOLECULE
O2
MYMOFIZGZYHOMD-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.55 Å
  • R-Value Free: 0.212 
  • R-Value Work: 0.167 
  • R-Value Observed: 0.169 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 54.807α = 90
b = 62.863β = 90
c = 153.594γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
XDSdata scaling
MOLREPphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
European CommissionItaly637295
European CommissionItaly312284

Revision History  (Full details and data files)

  • Version 1.0: 2019-09-18
    Type: Initial release
  • Version 1.1: 2020-07-29
    Changes: Database references, Derived calculations
  • Version 1.2: 2024-01-17
    Changes: Data collection, Database references, Refinement description