Neuraminidase protein of influenza B virus (NA (occasionally "IBV NA" for influenza B virus neuraminidase))

The **neuraminidase protein of influenza B virus** is one of two major surface glycoproteins on the influenza B virion, functioning as an enzyme that cleaves terminal sialic acid residues from host glycans[1][4][5]. Structurally, it exists as a homotetramer, with each subunit comprising a cytoplasmic tail, transmembrane domain, stalk, and a catalytic head forming a six-bladed beta-propeller structure[1][4][5]. This protein enables newly formed viral particles to be released from infected cells and also facilitates viral movement through the mucous layer of the host respiratory tract by destroying decoy sialic acid-containing receptors[1][4]. As a crucial part of the viral replication cycle, neuraminidase is a validated antiviral drug target, and several approved small-molecule inhibitors (neuraminidase inhibitors) directly block its enzymatic activity, preventing viral spread[3][5]. Resistance-conferring mutations in the enzyme have been observed and are monitored clinically[3].

Other names

NeuraminidaseSialidaseInfluenza B neuraminidaseNA protein (influenza B)

Competitive inhibition of the neuraminidase active site, preventing cleavage of sialic acids and thereby viral release from infected cells