Abstract
Two influenza A viruses whose hemagglutinin (HA) did not react with any of the reference antisera for the 13 recognized HA subtypes were isolated from mallard ducks in the USSR. Antigenic analysis by hemagglutination inhibition and double immunodiffusion tests showed that the HAs of these viruses are similar to each other but distinct from the HAs of other influenza A viruses. Nucleotide sequence analysis showed that these HA genes differ from each other by only 21 nucleotides. However, they differ from all other HA subtypes at the amino acid level by at least 31 % in HAI. Thus, we propose that the HAs of these viruses [A/Mallard/Gurjev/263/82 (H14N5) and A/Mallard/Gurjev/244/82 (H14N6)] belong to a previously unrecognized subtype, and are designated H14. Unlike any other HAs of influenza viruses, the H14 HAs contained lysine at the cleavage site between HA1 and HA2 instead of arginine. Experimental infection of domestic poultry and ferrets with A/Mallard/Gurjev/263/82 (H14N5) showed that the virus is avirulent for these animals. Based on comparative sequence analysis of different HA genes, it is suggested that differences of 30% or more at the amino acid level in HA1 constitute separate subtypes. Phylogenetic analysis of representatives of each HA subtype showed that H 14 is one of the most recently diverged lineages while H8 and H 12 branched off early during the evolution of the HA subtypes. These latter two subtypes (H8 and H12) have been isolated very infrequently in recent years, suggesting that these old subtypes may be disappearing from the influenza reservoirs in nature.
| Original language | English |
|---|---|
| Pages (from-to) | 759-767 |
| Number of pages | 9 |
| Journal | Virology |
| Volume | 179 |
| Issue number | 2 |
| DOIs | |
| State | Published - Dec 1990 |
Bibliographical note
Funding Information:We thank Albert Bean, John M. Freeman, Lili Wang, and Scott Krauss for excellent technical assistance; Clayton Naeve and the St. Jude Children’s Research Hospital Molecular Resource Center for preparation of oligonucleotides; Patricia Eddy and the St. Jude Children’s Research Hospital Molecular Biology Computer Facility for computer support; and David Swofford for PAUP software. This work was supported by Public Health Service Contract Al-52586 and Public Health Service Research Grants Al-08831, Al-29680, and Al-29599 from the National Institute of Allergy and Infectious Diseases; Cancer Center Support (CORE) Grant CA-21 765; and American Lebanese Syrian Associated Charities.
Funding
We thank Albert Bean, John M. Freeman, Lili Wang, and Scott Krauss for excellent technical assistance; Clayton Naeve and the St. Jude Children’s Research Hospital Molecular Resource Center for preparation of oligonucleotides; Patricia Eddy and the St. Jude Children’s Research Hospital Molecular Biology Computer Facility for computer support; and David Swofford for PAUP software. This work was supported by Public Health Service Contract Al-52586 and Public Health Service Research Grants Al-08831, Al-29680, and Al-29599 from the National Institute of Allergy and Infectious Diseases; Cancer Center Support (CORE) Grant CA-21 765; and American Lebanese Syrian Associated Charities.
| Funders | Funder number |
|---|---|
| Cancer Center Support | CA-21 765 |
| National Institute of Allergy and Infectious Diseases | R01AI008831 |
| U.S. Public Health Service | Al-29680, Al-08831, Al-52586, Al-29599 |
| American Lebanese Syrian Associated Charities |
ASJC Scopus subject areas
- Virology