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 ...
The genetic material of a virus is stored within a viral protein structure called the capsid. The capsid is a "shield" that protects the viral nucleic acids from getting degraded by host enzymes or other types of pesticides or pestilences. It also functions to attach the virion to its host, and enable the virion to penetrate the host cell membrane.
The M1 matrix protein and M2 proton channel share a segment, as do the non-structural protein (NS1) and the nuclear export protein (NEP). [1] For influenza A virus and influenza B virus, hemagglutinin (HA) and neuraminidase (NA) are encoded on one segment each, whereas influenza C virus and influenza D virus encode a hemagglutinin-esterase ...
This attachment is required for efficient transfer of flu virus genes into cells, a process that can be blocked by antibodies that bind to the hemagglutinin proteins. One genetic factor in distinguishing between human flu viruses and avian flu viruses is that avian influenza HA bind to alpha 2-3 sialic acid receptors while human influenza HA ...
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 ...
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.
A virus particle, also called a virion, consists of genes made from DNA or RNA which are surrounded by a protective coat of protein called a capsid. [23] The capsid is made of many smaller, identical protein molecules called capsomers. The arrangement of the capsomers can either be icosahedral (20-sided), helical, or more complex.
A viral envelope is the outermost layer of many types of viruses. [1] It protects the genetic material in their life cycle when traveling between host cells. Not all viruses have envelopes. A viral envelope protein or E protein is a protein in the envelope, which may be acquired by the capsid from an infected host cell.