Structure of influenza haemagglutinin at the pH of membrane fusion

Nature. 1994 Sep 1;371(6492):37-43. doi: 10.1038/371037a0.


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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Computer Graphics
  • Crystallography, X-Ray
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Hemagglutinins, Viral / chemistry*
  • Hemagglutinins, Viral / ultrastructure
  • Hydrogen-Ion Concentration
  • Membrane Fusion*
  • Molecular Sequence Data
  • Mutation
  • Orthomyxoviridae / chemistry
  • Orthomyxoviridae / ultrastructure
  • Peptide Fragments / chemistry
  • Protein Conformation
  • Protein Folding


  • Hemagglutinin Glycoproteins, Influenza Virus
  • Hemagglutinins, Viral
  • Peptide Fragments