5XKU

Crystal structure of hemagglutinin globular head from an H7N9 influenza virus in complex with a neutralizing antibody HNIgGA6


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.78 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.206 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural Insight into a Human Neutralizing Antibody against Influenza Virus H7N9

Chen, C.Liu, L.Xiao, Y.Cui, S.Wang, J.Jin, Q.

(2018) J. Virol. 92: --

  • DOI: 10.1128/JVI.01850-17

  • PubMed Abstract: 
  • Since its first emergence in East China in early 2013, many cases of avian influenza A H7N9 have been reported. The disease has extended to 22 provinces in mainland China and some surrounding areas. Strategies to combat viral infection are urgently n ...

    Since its first emergence in East China in early 2013, many cases of avian influenza A H7N9 have been reported. The disease has extended to 22 provinces in mainland China and some surrounding areas. Strategies to combat viral infection are urgently needed. We previously isolated a human monoclonal antibody, HNIgGA6, that neutralized H7N9 virus both in vitro and in vivo. In this study, we determined the crystal structure of viral hemagglutinin (HA) globular head bound to the Fab fragment of HNIgGA6. The crystal structure shows that the tip of the HNIgGA6 heavy-chain complementarity determining region 3 (HCDR3) directly interposes into the receptor binding site (RBS) and mimics, in many respects, the interaction of the sialic acid receptor. Three residues atY98, H183 and E190, that are critical to human cellular receptor binding, are also essential for HNIgGA6 recognition. At meanwhile, dual mutations at V186G and L226Q in RBS were able to disrupt viral HA1 binding with the antibody. Our study provides a better understanding of the mechanism for protective antibody recognition and sound foundation for the design of therapeutic drugs and vaccines against H7N9 influenza.ImportanceNeutralization by antibody is one of the most important mechanisms for a host to defend against viral infections. Human-originated antibody HNIgGA6 was generated in response to the natural infectious H7N9 virus and had potential use for suppression of H7N9 infection, with possible therapeutic implications. The crystal structure of HNIgGA6/HA1 complex provided new insight into the protective immune response to H7N9 virus in humans, as well as opinion for the development of effective H7N9 pandemic vaccines and antiviral molecules.


    Organizational Affiliation

    MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, P. R. China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Influenza a virus
A
328Influenza A virusGene Names: HA
Find proteins for R4NN21 (Influenza A virus)
Go to UniProtKB:  R4NN21
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
HNIgGA6 light chain
B
219N/A
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
HNIgGA6 heavy chain
C
233N/A
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

Download SDF File 
Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.78 Å
  • R-Value Free: 0.242 
  • R-Value Work: 0.206 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 70.983α = 90.00
b = 70.983β = 90.00
c = 283.728γ = 90.00
Software Package:
Software NamePurpose
PHENIXrefinement
HKL-2000data collection
Cootmodel building
XDSdata reduction
XDSdata scaling
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationCountryGrant Number
CAMS Innovation Fund for Medical Sciences (CIFMS)China2016-I2M-1-014

Revision History 

  • Version 1.0: 2017-11-29
    Type: Initial release
  • Version 1.1: 2017-12-20
    Type: Database references
  • Version 1.2: 2018-02-28
    Type: Database references