Search results
Results from the WOW.Com Content Network
The serotype of IAV is determined by the HA and neuraminidase (NA) proteins expressed on its surface. [12] Neuraminidase has 11 known subtypes; hence, influenza viruses are named according to the combinations of HA and NA proteins expressed (e.g., H1N1 and H5N2). [7] Structure of influenza, showing neuraminidase marked as NA and hemagglutinin ...
Influenza A viruses are further classified, based on the viral surface proteins hemagglutinin (HA or H) and neuraminidase (NA or N). 18 HA subtypes (or serotypes) and 11 NA subtypes of influenza A virus have been isolated in nature. Among these, the HA subtype 1-16 and NA subtype 1-9 are found in wild waterfowl and shorebirds and the HA ...
Two viral proteins; hemagglutinin (HA) and neuraminidase (NA), are inserted into the envelope and are exposed as spikes on the surface of the virion. Both proteins are antigenic; a host's immune system can react to them and produce antibodies in response. The M2 protein forms an ion channel in the envelope and is responsible for uncoating the ...
Viral neuraminidase cleaves terminal sialic acid residues from glycan structures on the surface of the infected cell. This promotes the release of progeny viruses and the spread of the virus from the host cell to uninfected surrounding cells. Neuraminidase also cleaves sialic acid residues from viral proteins, preventing aggregation of viruses.
Hemagglutinins are small proteins that extend from the surface of the virus membrane as spikes that are 135 Angstroms (Å) in length and 30-50 Å in diameter. [19] Each spike is composed of three identical monomer subunits, making the protein a homotrimer.
Figure 3 showed the structure of an influenza virus. The hemagglutinin (HA) surface proteins feature the influenza virus. The HA antigens of seasonal virus strains are the target for the influenza vaccines to trigger an immune response in the human body. During the manufacturing process, the virus’ gene is first obtained.
The envelope comprises a lipid bilayer membrane incorporating HA and NA (or HEF [26]) proteins extending outward from its exterior surface. HA and HEF [26] proteins have a distinct "head" and "stalk" structure. M2 proteins form proton channels through the viral envelope that are required for viral entry and exit. Influenza B viruses contain a ...
Examples of class II viral fusion proteins include the dengue virus E protein, and the west nile virus E protein. [5] [6] Class III: Structural conformation is a combination of features from Class I and Class II viral membrane fusion proteins. An example of a Class III viral fusion protein is the rabies virus glycoprotein, G. [6]