Structural polypeptides of antigenically distinct strains of influenza B virus.

Analyses of the polypeptide composition of influenza B viruses by 13 per cent SDS-polyacrylamide gel electrophoresis are reported. The viruses contained polypeptides of eight species ranging in molecular weight from 27,000 to 78,000. Four of them were glocypeptides and were selectively removed from the surface of the virion by Bromelain treatment. One of the blycopeptides was identified as viral neuraminidase. Three antigenically distinct strains of influenza virus, B/Lee/40, B/Massachusetts/1/71 and B/Hong Kong/5/72, showed an essentially identical electrophoretic picture, although strain-to-strain difference was observed in the migration rate of HA1 and HA2 polypeptides.