[Grouping of influenza A virus NP proteins]

A comparative study of influenza A virus NP proteins was carried out using peptide mapping. Thirty-five strains of all main serotypes of human and animal viruses were tested. The greatest diversity was found in NP proteins of human influenza viruses belonging to different serotypes, while within serotypes the variability is less pronounced. Four main groups of NP proteins were distinguished and designated NP0, NP1, NP2, and NP3. The NP0 group includes proteins of viruses of HON1 serotype, NP proteins of all avian viruses with the exception of A/shearwater/Australia/1/71 (Hav6Nav5), NP proteins of A/horse/Prague/56 (Heq1Neq1), A/swine/Iowa/1/30 (Hsw1N1), and A/whale/Pacific/76 (HONav2). The NP1 group comprises NP proteins of viruses of HIN1 serotype (with the exception of A/California/78), A/Singapore/57 (H2N2) and NP protein of A/New Jersey/76 (Hsw1N2) virus. The NP2 group includes NP proteins of H3N2 virus serotype and NP protein of A/California/78 (H1N1) virus. NP proteins of A/horse/Miami/63 (Heq2Neq2) and A/shearwater/Australia/1/71 viruses comprise NP3 group.