Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Cyclic - C3  (3D View)
Global Stoichiometry: Hetero 6-mer - A3B3 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

 3D View: Structure | Electron Density

Global Symmetry: Cyclic - C3  (3D View)
Global Stoichiometry: Hetero 6-mer - A3B3 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 334.68 kDa 
• Atom Count: 23611 
• Residue Count: 2950 
• Unique protein chains: 2

4JUG

Crystal structure of 1918 pandemic influenza virus hemagglutinin mutant D225G

• DOI: 10.2210/pdb4JUG/pdb

• Classification: VIRAL PROTEIN
• Organism(s): Influenza A virus (A/South Carolina/1/1918(H1N1))
• Expression System: Trichoplusia ni
• Mutation(s): Yes 


• Deposited: 2013-03-24 Released: 2013-05-01 
• Deposition Author(s): Zhang, W., Shi, Y., Qi, J., Gao, F., Li, Q., Fan, Z., Yan, J., Gao, G.F.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.70 Å
• R-Value Free: 0.267 
• R-Value Work: 0.207 
• R-Value Observed: 0.210 

Literature

Molecular basis of the receptor binding specificity switch of the hemagglutinins from both the 1918 and 2009 pandemic influenza A viruses by a D225G substitution

Zhang, W., Shi, Y., Qi, J., Gao, F., Li, Q., Fan, Z., Yan, J., Gao, G.F.

(2013) J Virol 87: 5949-5958

• PubMed: 23514882 
• DOI: 10.1128/JVI.00545-13
• Primary Citation of Related Structures:  
  4JTV, 4JTX, 4JU0, 4JUG, 4JUH, 4JUJ


• PubMed Abstract: 
  

Influenza A virus uses sialic acids as cell entry receptors, and there are two main receptor forms, α2,6 linkage or α2,3 linkage to galactose, that determine virus host ranges (mammalian or avian). The receptor binding hemagglutinins (HAs) of both 1918 and 2009 pandemic H1N1 (18H1 and 09H1, respectively) influenza A viruses preferentially bind to the human α2,6 linkage receptor. A single D225G mutation in both H1s switches receptor binding specificity from α2,6 linkage binding to dual receptor binding. However, the molecular basis for this specificity switch is not fully understood. Here, we show via H1-ligand complex structures that the D225G substitution results in a loss of a salt bridge between amino acids D225 and K222, enabling the key residue Q226 to interact with the avian receptor, thereby obtaining dual receptor binding. This is further confirmed by a D225E mutant that retains human receptor binding specificity with the salt bridge intact.

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Organizational Affiliation: 

CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Hemagglutinin	A, C, E, G, I, K	324	Influenza A virus (A/South Carolina/1/1918(H1N1))	Mutation(s): 1  Gene Names: HA
Find proteins for Q9WFX3 (Influenza A virus (strain A/Brevig Mission/1/1918 H1N1)) Explore Q9WFX3  Go to UniProtKB:  Q9WFX3

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Hemagglutinin	B, D, F, H, J, L	170	Influenza A virus (A/South Carolina/1/1918(H1N1))	Mutation(s): 0  Gene Names: HA
Find proteins for Q9WFX3 (Influenza A virus (strain A/Brevig Mission/1/1918 H1N1)) Explore Q9WFX3  Go to UniProtKB:  Q9WFX3

Oligosaccharides

Help

Entity ID: 3
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	M, N, P, Q, R, T	2		N-Glycosylation

Entity ID: 4
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	O, S	3		N-Glycosylation

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.70 Å
• R-Value Free: 0.267 
• R-Value Work: 0.207 
• R-Value Observed: 0.210 
• Space Group: P 3

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 120.856	α = 90
b = 120.856	β = 90
c = 235.724	γ = 120

Software Package:

Software Name	Purpose
MAR345dtb	data collection
PHASER	phasing
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-03-24 
• Released Date: 2013-05-01 
Deposition Author(s): Zhang, W., Shi, Y., Qi, J., Gao, F., Li, Q., Fan, Z., Yan, J., Gao, G.F.

Revision History 

• Version 1.0: 2013-05-01
  Type: Initial release
  
• Version 1.1: 2013-08-07
  Changes: Database references
• Version 2.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Advisory, Atomic model, Data collection, Database references, Derived calculations, Structure summary