[Protein variability of influenza A viruses].

Comparative studies of nonstructural (NS) protein, nucleoprotein protein (NP) and membrane protein (M) of some influenza virus strains were performed by peptide mapping. The greatest differences were found in peptide maps of NS and NP proteins of influenza viruses whereas tryptic 35S-methionine maps of membrane proteins were much less variable. No correlation between the oligopeptide composition of NP, M, and NS proteins and the natural host range of the influenza A viruses under study was found.