当前位置： SCI文献检索 > JOURNAL OF VIROLOGY期刊下所有文献 > Role of Neuraminidase in Influenza A(H7N9) Virus Receptor Binding.

Role of Neuraminidase in Influenza A(H7N9) Virus Receptor Binding.

Abstract：

:Influenza A(H7N9) viruses have caused a large number of zoonotic infections since their emergence in 2013. They remain a public health concern due to the repeated high levels of infection with these viruses and their perceived pandemic potential. A major factor that determines influenza A virus fitness and therefore transmissibility is the interaction of the surface glycoproteins hemagglutinin (HA) and neuraminidase (NA) with the cell surface receptor sialic acid. Typically, the HA is responsible for binding to the sialic acid to allow virus internalization and the NA is a sialidase responsible for cleaving sialic acid to aid virus spread and release. N9 NA has previously been shown to have receptor binding properties mediated by a sialic acid binding site, termed the hemadsorption (Hb) site, which is discrete from the enzymatically active sialidase site. This study investigated the N9 NA from a zoonotic H7N9 virus strain in order to determine its possible role in virus receptor binding. We demonstrate that this N9 NA has an active Hb site which binds to sialic acid, which enhances overall virus binding to sialic acid receptor analogues. We also show that the N9 NA can also contribute to receptor binding due to unusual kinetic characteristics of the sialidase site which specifically enhance binding to human-like α2,6-linked sialic acid receptors.IMPORTANCE The interaction of influenza A virus glycoproteins with cell surface receptors is a major determinant of infectivity and therefore transmissibility. Understanding these interactions is important for understanding which factors are necessary to determine pandemic potential. 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. Previous studies showed that the NA proteins of the N9 subtype can bind sialic acid via a separate binding site distinct from the sialidase active site. This study demonstrates for purified protein and virus that the NA of the zoonotic H7N9 viruses has a binding capacity via both the secondary binding site and unusual kinetic properties of the sialidase site which promote receptor binding via this site and which enhance binding to human-like receptors. This could have implications for understanding human-to-human transmission of these viruses.

journal_name

J Virol

journal_title

Journal of virology

authors

Benton DJ,Wharton SA,Martin SR,McCauley JW

doi

10.1128/JVI.02293-16

subject

Has Abstract

pub_date

2017-05-12 00:00:00

issue

eissn

0022-538X

issn

1098-5514

pii

JVI.02293-16

journal_volume

pub_type

杂志文章

在线工具

Role of Neuraminidase in Influenza A(H7N9) Virus Receptor Binding.