4ONT

Ternary host recognition complex of complement factor H, C3d, and sialic acid


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.172 
  • R-Value Observed: 0.175 

wwPDB Validation   3D Report Full Report



Literature

Structural basis for sialic acid-mediated self-recognition by complement factor H.

Blaum, B.S.Hannan, J.P.Herbert, A.P.Kavanagh, D.Uhrin, D.Stehle, T.

(2015) Nat Chem Biol 11: 77-82

  • DOI: 10.1038/nchembio.1696
  • Primary Citation of Related Structures:  
    4ONT

  • PubMed Abstract: 
  • The serum protein complement factor H (FH) ensures downregulation of the complement alternative pathway, a branch of innate immunity, upon interaction with specific glycans on host cell surfaces. Using ligand-based NMR, we screened a comprehensive set of ...

    The serum protein complement factor H (FH) ensures downregulation of the complement alternative pathway, a branch of innate immunity, upon interaction with specific glycans on host cell surfaces. Using ligand-based NMR, we screened a comprehensive set of sialylated glycans for binding to FH and solved the crystal structure of a ternary complex formed by the two C-terminal domains of FH, a sialylated trisaccharide and the complement C3b thioester-containing domain. Key residues in the sialic acid binding site are conserved from mice to men, and residues linked to atypical hemolytic uremic syndrome cluster within this binding site, suggesting a possible role for sialic acid as a host marker also in other mammals and a critical role in human renal complement homeostasis. Unexpectedly, the FH sialic acid binding site is structurally homologous to the binding sites of two evolutionarily unrelated proteins. The crystal structure also advances our understanding of bacterial immune evasion strategies.


    Organizational Affiliation

    1] Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany. [2] Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Complement factor H DEF129Homo sapiensMutation(s): 0 
Gene Names: CFHHFHF1HF2
Find proteins for P08603 (Homo sapiens)
Explore P08603 
Go to UniProtKB:  P08603
NIH Common Fund Data Resources
PHAROS:  P08603
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Complement C3d fragment ABC317Homo sapiensMutation(s): 1 
Gene Names: C3CPAMD1
Find proteins for P01024 (Homo sapiens)
Explore P01024 
Go to UniProtKB:  P01024
NIH Common Fund Data Resources
PHAROS:  P01024
Protein Feature View
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  • Reference Sequence
Oligosaccharides

Help

Entity ID: 3
MoleculeChainsChain Length2D Diagram Glycosylation3D Interactions
N-acetyl-alpha-neuraminic acid-(2-3)-beta-D-galactopyranose-(1-4)-beta-D-glucopyranose
G, H, I
3 N/A Oligosaccharides Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.172 
  • R-Value Observed: 0.175 
  • Space Group: P 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 75.459α = 112.5
b = 82.536β = 110.71
c = 85.752γ = 99.98
Software Package:
Software NamePurpose
DA+data collection
CCP4model building
REFMACrefinement
XDSdata reduction
XDSdata scaling
CCP4phasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-11-26
    Type: Initial release
  • Version 1.1: 2014-12-03
    Changes: Database references
  • Version 1.2: 2015-01-14
    Changes: Database references
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Database references, Derived calculations, Structure summary