Influenza A and B neuraminidase (NA) (NA)

Influenza A and B neuraminidase (NA) is a critical surface glycoprotein and enzyme found on the envelope of influenza viruses (StatPearls, 2023). Its primary biological function is to act as a sialidase, cleaving terminal sialic acid residues from glycoproteins and glycolipids on the host cell surface and the viral envelope (UniProt, 2024). This enzymatic activity is essential for the release of newly synthesized progeny virions from infected cells, preventing their aggregation and allowing the infection to spread throughout the respiratory tract (NIH, 2023). In the context of disease, NA plays a pivotal role in the pathogenesis of seasonal and pandemic influenza by facilitating viral dissemination and helping the virus penetrate the mucus layer of the airway (PubMed, 2022). Because of its conserved active site and essential role in the viral life cycle, NA is a primary target for antiviral therapy (CDC, 2023). Drugs known as neuraminidase inhibitors, such as oseltamivir and zanamivir, competitively bind to the enzyme's active site to block its activity, effectively halting viral replication and reducing the severity and duration of symptoms (PubChem, 2024).

Other names

SialidaseExo-alpha-sialidaseN-acetylneuraminate glycohydrolaseNAInfluenza virus neuraminidase

Neuraminidase inhibitors competitively bind to the active site of the enzyme, preventing the cleavage of terminal sialic acid residues on host cell surfaces and viral glycoproteins (StatPearls, 2023). This action traps newly formed virions on the surface of the infected cell and within respiratory secretions, thereby inhibiting the spread of the virus to uninfected cells (PubMed, 2022).