ArticlePLoS pathogens2014
A single amino acid in the stalk region of the H1N1pdm influenza virus HA protein affects viral fusion, stability and infectivity.
Article in PLoS pathogens, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 103 papers.
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Who cites it
103 citing papers in PubMed, 156 citations in OpenAlex.
- Nasal shedding of vaccine viruses after immunization with a Russian-backbone live attenuated influenza vaccine in India.Influenza and other respiratory viruses · 2023Trial
- Immunogenicity and Viral Shedding of Russian-Backbone, Seasonal, Trivalent, Live, Attenuated Influenza Vaccine in a Phase II, Randomized, Placebo-Controlled Trial Among Preschool-Aged Children in Urban Bangladesh.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2019Trial
- Effect of a Russian-backbone live-attenuated influenza vaccine with an updated pandemic H1N1 strain on shedding and immunogenicity among children in The Gambia: an open-label, observational, phase 4 study.The Lancet. Respiratory medicine · 2019Trial
- Efficacy of a Russian-backbone live attenuated influenza vaccine among children in Senegal: a randomised, double-blind, placebo-controlled trial.The Lancet. Global health · 2016Trial
- HA thermostability mutations S84F, G167N, and D168N potentiate H9N2 virus transmission in a warming environment.Emerging microbes & infections · 2026Article
- New determinant of influenza hemagglutinin cleavability identified through random mutagenesis for acid-stabilizing mutations.Microbiology spectrum · 2026Article
- Pathogenicity and immune response of turkey A(H1N2) influenza virus of swine-origin on turkeys and mice.Veterinary research · 2026Article
- Identification of thermostability-enhancing mutations in H9N2 avian influenza virus hemagglutinin.Journal of virology · 2026Article
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- Structural vaccinology expedites rational design of next-generation vaccines for influenza and respiratory syncytial virus.Virologica Sinica · 2026Review
- Advances and prospects of mucosal vaccination in the prevention and control of avian influenza.Frontiers in immunology · 2026Review
- Resistance Mutations to Broadly Neutralizing Antibodies Destabilize Hemagglutinin and Attenuate H1N1 Influenza Virus.Viruses · 2025Article
- Host switching mutations in H5N1 influenza hemagglutinin suppress site-specific activation dynamics.Nature communications · 2025Article
- Host Switching Mutations in H5N1 Influenza Hemagglutinin Suppress Site-specific Activation Dynamics.bioRxiv : the preprint server for biology · 2025Article
- Review
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- Use of equine H3N8 hemagglutinin as a broadly protective influenza vaccine immunogen.NPJ vaccines · 2024Article
- An Optimised Live Attenuated Influenza Vaccine Ferret Efficacy Model Successfully Translates H1N1 Clinical Data.Vaccines · 2024Article
- Engineering a cleaved, prefusion-stabilized influenza B virus hemagglutinin by identification and locking of all six pH switches.PNAS nexus · 2024Article
- Molecular Markers and Mechanisms of Influenza A Virus Cross-Species Transmission and New Host Adaptation.Viruses · 2024Review
43 more citing papers are in PubMed but not listed here.
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Authors and funding
3 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The 2009 H1N1 pandemic (H1N1pdm) viruses have evolved to contain an E47K substitution in the HA2 subunit of the stalk region of the hemagglutinin (HA) protein. The biological significance of this single amino acid change was investigated by comparing A/California/7/2009 (HA2-E47) with a later strain, A/Brisbane/10/2010 (HA2-K47). The E47K change was found to reduce the threshold pH for membrane fusion from 5.4 to 5.0. An inter-monomer salt bridge between K47 in HA2 and E21 in HA1, a neighboring highly conserved residue, which stabilized the trimer structure, was found to be responsible for the reduced threshold pH for fusion. The higher structural and acid stability of the HA trimer caused by the E47K change also conferred higher viral thermal stability and infectivity in ferrets, suggesting a fitness advantage for the E47K evolutionary change in humans. Our study indicated that the pH of HA fusion activation is an important factor for influenza virus replication and host adaptation. The identification of this genetic signature in the HA stalk region that influences vaccine virus thermal stability also has significant implications for influenza vaccine production.
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