Related Experiment Video

Updated: Jul 23, 2026

Quantitative Analyses of all Influenza Type A Viral Hemagglutinins and Neuraminidases using Universal Antibodies in Simple Slot Blot Assays
13:12

Quantitative Analyses of all Influenza Type A Viral Hemagglutinins and Neuraminidases using Universal Antibodies in Simple Slot Blot Assays

Published on: April 4, 2011

Three-dimensional structure of an antigenic mutant of the influenza virus haemagglutinin

M Knossow, R S Daniels, A R Douglas

    Nature
    |October 18, 1984
    PubMed

    Antigenic variation in the haemagglutinin (HA) glycoprotein of influenza virus is associated with recurrent epidemics of respiratory disease in man (for review see ref. 1). We have examined the size of structural changes necessary to alter the antigenicity of HA by determining the three-dimensional structure of the HA from an antigenic mutant containing a single amino acid substitution which was selected by growth of virus in the presence of monoclonal antibodies. Here we present evidence that the simple addition of an amino acid side chain which results in only minor local distortions of the structure of the HA is sufficient structural alteration for a virus to escape neutralization by a monoclonal antibody. Our results also demonstrate that single amino acid substitutions can cause only local changes in the HA structure, verifying the assumption made in several studies to locate antigenic sites on the HA and other molecules, and indicate that proposals of large conformational changes to account for variations in HA antigenicity are unnecessary in this case. The structure of the variant antigen has independently been successfully predicted (M. Karplus, personal communication).

    More Related Videos

    Generation of Escape Variants of Neutralizing Influenza Virus Monoclonal Antibodies07:55

    Generation of Escape Variants of Neutralizing Influenza Virus Monoclonal Antibodies

    Published on: August 29, 2017

    Subnanometer-Resolution Structural Determination of Hemagglutinin from Cryo-Electron Tomography of Influenza Viruses08:19

    Subnanometer-Resolution Structural Determination of Hemagglutinin from Cryo-Electron Tomography of Influenza Viruses

    Published on: November 7, 2025

    Related Concept Videos

    Viral Structure00:56

    Viral Structure

    Viruses are extraordinarily diverse in shape and size, but they all have several structural features in common. All viruses have a core that contains a DNA- or RNA-based genome. The core is surrounded by a protective coat of proteins called the capsid. The capsid is composed of subunits called capsomeres. The capsid and genome-containing core are together known as the nucleocapsid.
    Viral Mutations00:36

    Viral Mutations

    A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material for adaptive...
    Antibody Structure01:10

    Antibody Structure

    Overview
    Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
    The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
    Antibodies consist of four polypeptide chains: two identical heavy...
    Leaky Scanning02:28

    Leaky Scanning

    During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA.  Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
    Influenza01:27

    Influenza

    Influenza is an acute, highly communicable viral disease that affects the respiratory tract and is responsible for seasonal epidemics worldwide. Influenza A is the most prevalent type associated with widespread outbreaks and is subtyped based on two surface glycoproteins: hemagglutinin (H) and neuraminidase (N), as in H1N1. These glycoproteins are essential for viral infectivity, transmission, and immune recognition. Transmission occurs primarily through respiratory droplets and contaminated...
    Inhibitors Of Virion Release01:25

    Inhibitors Of Virion Release

    Viral replication and dissemination rely on efficient mechanisms for host cell entry, genome replication, assembly, and release. Influenza viruses, such as types A and B, are negative-sense single-stranded RNA viruses with a segmented genome, that depend on two critical surface glycoproteins to carry out these processes: hemagglutinin (HA) and neuraminidase (NA). HA initiates infection by binding to sialic acid residues on the surface of host epithelial cells, facilitating receptor-mediated...