Neuraminidase (H7N9) (NA)

Neuraminidase (NA) is a critical surface glycoprotein of the H7N9 influenza virus, an avian-origin strain that has caused significant human morbidity and mortality since its emergence in 2013 [1, 15]. As a glycosyl hydrolase (EC 3.2.1.18), NA functions by cleaving terminal sialic acid residues from host cell receptors and nascent viral particles, a process essential for the release of progeny virions from infected cells and their subsequent spread through the respiratory tract [2, 12]. Beyond its role in viral egress, the N9 subtype of NA in H7N9 viruses possesses a unique hemadsorption (Hb) site that can also contribute to viral attachment by binding sialic acids, potentially enhancing viral fitness and transmissibility [15]. NA is the primary target for the class of antiviral drugs known as neuraminidase inhibitors (NAIs), including oseltamivir, zanamivir, and peramivir [11, 14]. However, the therapeutic utility of these drugs is increasingly challenged by the emergence of resistance-conferring mutations, most notably the R292K substitution, which significantly reduces drug susceptibility without compromising viral replication or virulence [1, 5, 11]. Monitoring these mutations is vital for clinical management, as H7N9 viruses can rapidly develop resistance during treatment [3, 11].

Other names

SialidaseNAN9 neuraminidaseExo-alpha-sialidase

Neuraminidase inhibitor