Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report

Global Symmetry: Cyclic - C3  (3D View)
Global Stoichiometry: Homo 3-mer - A3 

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

Macromolecule Content

• Total Structure Weight: 57.13 kDa 
• Atom Count: 3129 
• Modelled Residue Count: 379 
• Deposited Residue Count: 495 
• Unique protein chains: 2

1HTM

STRUCTURE OF INFLUENZA HAEMAGGLUTININ AT THE PH OF MEMBRANE FUSION

• PDB DOI: 10.2210/pdb1HTM/pdb

• Classification: VIRAL PROTEIN
• Organism(s): uncultured beta proteobacterium UMTRA-608
• Mutation(s): No 


• Deposited: 1994-11-02 Released: 1995-02-14 
• Deposition Author(s): Bullough, P.A., Hughson, F.M., Skehel, J.J., Wiley, D.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.291 
• R-Value Work: 0.222 
• R-Value Observed: 0.222 

Literature

Structure of influenza haemagglutinin at the pH of membrane fusion.

Bullough, P.A., Hughson, F.M., Skehel, J.J., Wiley, D.C.

(1994) Nature 371: 37-43

• PubMed: 8072525 
• DOI: 10.1038/371037a0
• Primary Citation of Related Structures:  
  1HTM


• PubMed Abstract: 
  

Low pH induces a conformational change in the influenza virus haemagglutinin, which then mediates fusion of the viral and host cell membranes. The three-dimensional structure of a fragment of the haemagglutinin in this conformation reveals a major refolding of the secondary and tertiary structure of the molecule. The apolar fusion peptide moves at least 100 A to one tip of the molecule. At the other end a helical segment unfolds, a subdomain relocates reversing the chain direction, and part of the structure becomes disordered.

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Related Citations: 

• Crystals of a Fragment of Influenza Haemagglutinin in the Low Ph Induced Conformation
  Bullough, P.A., Hughson, F.M., Treharne, A.C., Ruigrok, R.W.H., Skehel, J.J., Wiley, D.C.
  (1994) J Mol Biol 236: 1262

• Refinement of the Influenza Virus Hemagglutinin by Simulated Annealing
  Weis, W.I., Brunger, A.T., Skehel, J.J., Wiley, D.C.
  (1990) J Mol Biol 212: 737

• Studies on the Structure of the Influenza Virus Haemagglutinin at the Ph of Membrane Fusion
  Ruigrok, R.W.H., Aitken, A., Calder, L.J., Martin, S.R., Skehel, J.J., Wharton, S.A., Weis, W., Wiley, D.C.
  (1988) J Gen Virol 69: 2785

• Analyses of the Antigenicity of Influenza Haemagglutinin at the Ph Optimum for Virus-Mediated Membrane Fusion
  Daniels, R.S., Douglas, A.R., Skehel, J.J.
  (1983) J Gen Virol 64: 1264

• Changes in the Conformation of Influenza Virus Hemagglutinin at the Ph Optimum of Virus-Mediated Membrane Fusion
  Skehel, J.J., Bayley, P.M., Brown, E.B., Martin, S.R., Waterfield, M.D., White, J.M., Wilson, I.A., Wiley, D.C.
  (1982) Proc Natl Acad Sci U S A 79: 93

• Structure of the Haemagglutinin Membrane Glycoprotein of Influenza Virus at 3 Angstroms Resolution
  Wilson, I.A., Skehel, J.J., Wiley, D.C.
  (1981) Nature 289: 366

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
HEMAGGLUTININ HA1 CHAIN	A, C, E	27	uncultured beta proteobacterium UMTRA-608	Mutation(s): 0
UniProt
Find proteins for P03437 (Influenza A virus (strain A/Aichi/2/1968 H3N2)) Explore P03437  Go to UniProtKB:  P03437

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
HEMAGGLUTININ HA2 CHAIN	B, D, F	138	uncultured beta proteobacterium UMTRA-608	Mutation(s): 0
UniProt
Find proteins for P03437 (Influenza A virus (strain A/Aichi/2/1968 H3N2)) Explore P03437  Go to UniProtKB:  P03437

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.291 
• R-Value Work: 0.222 
• R-Value Observed: 0.222 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 168.7	α = 90
b = 231.7	β = 90
c = 53.8	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1994-11-02 
• Released Date: 1995-02-14 
Deposition Author(s): Bullough, P.A., Hughson, F.M., Skehel, J.J., Wiley, D.C.

Revision History  

• Version 1.0: 1995-02-14
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance