A novel amino acid substitution at the receptor-binding site on the hemagglutinin of H3N2 influenza A viruses isolated from 6 cases with acute encephalopathy during the 1997-1998 season in Tokyo

Arch Virol. 1999;144(1):147-55. doi: 10.1007/s007050050491.


We analyzed the hemagglutinin (HA) genes of influenza A viruses consisting of 6 strains isolated from cerebrospinal fluids of patients with encephalopathy and 3 isolates from throat washes of patients without central nervous system symptoms during the 1997-1998 season in Tokyo. Aligned 9 amino acid sequences showed 7 common substitutions compared with A/Wuhan/359/95 (vaccine strain used in the season in Japan), which were allocated to three different antigenic sites on the H3 HA molecule. It is noted that a novel substitution at the receptor-binding site (Tyr-137 to Phe) was found exclusively in the isolates from the patients with encephalopathy.

MeSH terms

  • Amino Acid Sequence
  • Amino Acid Substitution
  • Binding Sites / genetics
  • Brain Diseases / virology*
  • Child
  • Child, Preschool
  • Female
  • Hemagglutinin Glycoproteins, Influenza Virus / genetics*
  • Humans
  • Infant
  • Influenza A Virus, H3N2 Subtype*
  • Influenza A virus / genetics*
  • Influenza A virus / pathogenicity
  • Influenza, Human / physiopathology
  • Influenza, Human / virology*
  • Male
  • Molecular Sequence Data
  • Point Mutation*
  • Receptors, Virus / physiology
  • Virulence / genetics


  • Hemagglutinin Glycoproteins, Influenza Virus
  • Receptors, Virus

Associated data

  • GENBANK/AB013807
  • GENBANK/AB013809
  • GENBANK/AB013813
  • GENBANK/AB014060
  • GENBANK/AB014061
  • GENBANK/AB014062