Table of Contents
What is the function of neuraminidase?
Neuraminidase cleaves the sialic acid molecule, thereby freeing the virus to infect other cells in the host organism.
What is the role of neuraminidase in influenza?
Influenza A viruses generally mediate binding to cell surface sialic acid receptors via the hemagglutinin (HA) glycoprotein, with the neuraminidase (NA) glycoprotein being responsible for cleaving the receptor to allow virus release.
What is the structure of hemagglutinin?
Hemagglutinin consists of a globular head and a stem. The globular head consists of three chains, Chains A, C, and E. The stem of the protein consists of three chains as well, Chains B, D, and F.
What is neuraminidase made of?
Neuraminidase is an exosialidase (EC 3.2. 1.18) which cleaves α-ketosidic linkage between the sialic (N-acetylneuraminic) acid and an adjacent sugar residue [1]. The amino acid sequence of NA is coded by the 6th RNA segment.
What type of enzyme is neuraminidase?
glycoside hydrolase enzymes
Neuraminidase (Sialidase) enzymes are glycoside hydrolase enzymes that cleave (cut) the glycosidic linkages of neuraminic acids. Neuraminidase enzymes are a large family, found in a range of organisms.
What is the function of hemagglutinin and neuraminidase?
Hemagglutinin-neuraminidase (HN) protein, which is responsible for virus attachment, interacts with the fusion protein in a virus type-specific manner to induce efficient membrane fusion.
What is the meaning of neuraminidase?
Definition of neuraminidase : a hydrolytic enzyme that occurs on the surface of the pneumococcus, influenza-causing viruses, and some paramyxoviruses as an antigen and that splits mucoproteins by breaking a glucoside link.
What type of protein is neuraminidase?
How many amino acids are in neuraminidase?
The RNA segment contains 1,557 virus-specific nucleotides, and the protein encoded by the longest open reading frame has a total of 466 amino acids with a molecular weight of 51,721.
What are the two groups of neuraminidase?
Nine subtypes of influenza A NA are divided into two phylogenic groups. The first group consists of the neuraminidases of N1, N4, N5 and N8 subtypes, and the second one consists of N2, N3, N6 N7 and N9 subtypes [3]. The enzyme of the influenza C virus does not belong to the neuraminidase group.
What is the substrate specificity of N2 neuraminidase?
The N2 neuraminidase of human influenza virus has acquired a substrate specificity complementary to the hemagglutinin receptor specificity. Virol. 1991;180:10–15.
Is the enzyme of influenza C virus a neuraminidase?
The enzyme of the influenza C virus does not belong to the neuraminidase group. It promotes the O-deacetylation of the N-acetyl-9-O-acetylneuraminic acid, i.e. it belongs to the esterase family and will not be considered in this review.
Are neuraminidase inhibitors antivirals?
In addition, data on neuraminidase inhibitors (as antivirals) are provided, along with considerations on the mechanisms of resistance of modern influenza viruses to those antivirals. The influenza virus is an enveloped (-)RNA containing a virus with a segmented genome, and its genetic material is coded by eight RNA-segments.