Neuraminidase (Influenza A virus H1N1 pdm09) (NA)

Neuraminidase (NA) is a major surface glycoprotein and essential enzyme of the influenza A virus, specifically the H1N1 pandemic 2009 (pdm09) strain. It functions as a sialidase, catalyzing the cleavage of terminal sialic acid residues from host cell receptors and viral glycoproteins. This activity is critical for the release of newly formed virions from the surface of infected cells and facilitates the movement of the virus through the respiratory tract mucus to reach new target cells. As a primary therapeutic target, NA is inhibited by drugs such as oseltamivir and zanamivir, which block the active site to prevent viral dissemination. The emergence of resistance-conferring mutations, most notably the H275Y substitution, remains a significant challenge in the clinical management of infections caused by this strain (Source: UniProt C3W5S7; CDC). Monitoring viral load and enzymatic activity is essential for assessing treatment efficacy. The protein's structure consists of a head, stalk, transmembrane domain, and cytoplasmic tail, with the head containing the catalytic site. NA also plays a role in preventing the aggregation of viral particles. Its high variability between strains necessitates constant surveillance for seasonal and pandemic preparedness. Overall, NA remains a cornerstone of anti-influenza drug development and public health monitoring.

Other names

SialidaseN1 neuraminidaseH1N1pdm09 NAExo-alpha-sialidaseNeuraminidase of influenza Apdm09-like strain

Neuraminidase inhibitors competitively bind to the highly conserved active site of the neuraminidase enzyme, mimicking the transition state of sialic acid cleavage. This prevents the enzyme from removing terminal sialic acid residues from host cell receptors and viral glycoproteins, which traps progeny virions on the cell surface and within respiratory mucus, thereby halting the spread of infection to adjacent cells (Source: PubMed PMID: 22132187; StatPearls).