Influenza A virus Neuraminidase (subtype N2) (NA (N2))

The H9N2 influenza virus neuraminidase (NA) protein is a critical membrane-bound enzyme and surface glycoprotein involved in the final stages of the viral life cycle. Functioning as an exo-alpha-sialidase, it catalyzes the cleavage of terminal alpha-ketosidically linked sialic acids from host cell receptors and newly formed virions [UniProt: P03472]. This enzymatic activity is essential for releasing progeny viruses from the host cell surface, preventing their aggregation, and facilitating their spread through the respiratory mucus layer to uninfected cells [PubMed: 22230491]. In the context of H9N2—an avian influenza subtype with significant zoonotic and pandemic potential—the N2 neuraminidase is a primary target for antiviral intervention. Therapeutic agents known as neuraminidase inhibitors (NAIs), such as oseltamivir and zanamivir, competitively bind the enzyme's active site to halt viral egress and limit the severity of infection [NIH: StatPearls - Influenza Antivirals]. Monitoring structural changes in this protein is vital for identifying emerging drug-resistant strains, such as those carrying the R292K or E119V mutations, which can compromise standard treatment protocols [PubMed: 23671548].

Other names

NeuraminidaseSialidaseExo-alpha-sialidaseN2 neuraminidaseNAEC 3.2.1.18

Neuraminidase inhibitors (NAIs) function as competitive inhibitors that bind to the highly conserved active site of the neuraminidase enzyme, mimicking the transition state of sialic acid cleavage to prevent the release of progeny virions from infected host cells.