Neuraminidase (Influenza A virus (H1N1)pdm09) (NA)

Influenza A(H1N1)pdm09 neuraminidase (NA) is a critical surface glycoprotein of the 2009 pandemic H1N1 influenza virus, playing a vital role in the viral life cycle (UniProt C3W5S3). As an exosialidase (EC 3.2.1.18), it catalyzes the cleavage of terminal sialic acid residues from host cell receptors and viral glycoproteins (PubMed: 20478092). This enzymatic activity is essential for the release of newly formed virions from the surface of infected cells, preventing their aggregation and facilitating their spread to uninfected cells (NIH: PMC4810786). Additionally, NA helps the virus penetrate the sialic acid-rich mucus of the respiratory tract to reach target epithelial cells (PubMed: 24501060). It is the primary target for the neuraminidase inhibitor (NAI) class of antiviral drugs, including oseltamivir, zanamivir, and peramivir (CDC). These drugs bind to the highly conserved active site of the enzyme, effectively halting viral replication and reducing the severity of the infection. However, the therapeutic utility of these drugs is threatened by the emergence of resistance mutations, such as the H274Y substitution, which significantly reduces drug binding affinity (PubMed: 21106910). Beyond its role as a drug target, NA is a key antigen for the host immune response and a critical component in the design of seasonal and pandemic influenza vaccines (NIH: PMC7120343).

Other names

SialidaseN1 neuraminidasepH1N1 neuraminidase2009 pandemic H1N1 neuraminidaseExosialidase

Competitive inhibition of the neuraminidase enzyme, which prevents the cleavage of sialic acid residues and blocks the release of progeny virions from infected host cells.