Mutation detail:
| Mutation site | H274Y |
| Virus | Influenzavirus A H1N1 |
Mutation level  |
Amino acid Level |
| Gene/protein/region type | NA |
| Gene ID | 23308118 |
| Country | Oceania, South East Asia and South Africa |
| Mutation type |
nonsynonymous mutation |
| Genotype/subtype/clade | - |
| Sample |
Human |
| Variants | - |
| Viral reference sequence | CY033624.1 |
| Drug/antibody/vaccine | oseltamivir |
| Transmissibility |
- |
| Transmission mechanism | - |
| Pathogenicity |
- |
| Pathogenicity mechanism | - |
| Immune escape mutation | - |
| Immune escape mechanism | - |
| RT-PCR primers probes | - |
Protein detail:
| Protein name | Neuraminidase |
| Uniprot protein ID | C3W6G3 |
| Protein length | 469 amino acids |
| Protein description | The NA assembles as a tetramer of four identical polypeptides and, when embedded in the envelope of the virus, accounts for approximately 10-20% of the total glycoproteins on the virion surface, with about 40-50 NA spikes and 300-400 HA spikes on an average sized virion of 120 nm. The four monomers, each of approximately 470 amino acids, fold into four distinct structural domains: the cytoplasmic tail, the transmembrane region, the stalk, and the catalytic head. The NA catalyzes the removal of terminal sialic acid residues from viral and cellular glycoconjugates. Cleaves off the terminal sialic acids on the glycosylated HA during virus budding to facilitate virus release. Additionally helps virus spread through the circulation by further removing sialic acids from the cell surface. These cleavages prevent self-aggregation and ensure the efficient spread of the progeny virus from cell to cell. Otherwise, infection would be limited to one round of replication. Described as a receptor-destroying enzyme because it cleaves a terminal sialic acid from the cellular receptors. May facilitate viral invasion of the upper airways by cleaving the sialic acid moities on the mucin of the airway epithelial cells. |
Literature information:
| Pubmed ID | 19501261 |
| Clinical information | No |
| Disease | - |
| Published year | 2009 |
| Journal | Antiviral Research |
| Title | Emergence and spread of oseltamivir-resistant A(H1N1) influenza viruses in Oceania, South East Asia and South Africa |
| Author | Aeron C Hurt,Joanne Ernest,Yi-Mo Deng,Pina Iannello,Terry G Besselaar |
| Evidence | As well as the H274Y mutation in the NA conferring oseltamivir resistance, the majority of mutant viruses (87%) collected in Australia after July 2008 also contained two amino acid differences in the HA gene (N187S and G189N) compared to H274Y viruses circulating in the Northern Hemisphere or Australia prior to that time |