Characterization of the hemagglutinin receptor specificity and neuraminidase substrate specificity of clinical isolates of human influenza A viruses

Couceiro, J. N. S. S.; Baum, Linda G.

doi:10.1590/s0074-02761994000400015

Cited by 12 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The general patterns of NA substrate preference of avian and seasonal influenza viruses are in agreement with previously published data [10,[27][28][29] . The similar sialic acid preference between HA and NA of the same group of viruses suggests that compatibility between HA and NA is important for optimal viral infection.…”

Section: ��supporting

confidence: 91%

Substrate specificity of avian influenza H5N1 neuraminidase

Onsirisakul

Nakakita

Boonarkart

et al. 2014

WJV

View full text Add to dashboard Cite

fluorescence Amplex Red assay. This method can identify the preference of α2,6-linked sialic acid or α2,3-linked sialic acid. Moreover, to avoid the bias of input virus, reverse genetic virus using NA gene from human isolated H5N1 were generated and used to compare with the seasonal influenza virus. Lastly, the substrate specificity profile was further confirmed by high-performance liquid chromatography (HPLC) analysis of the enzymatic product. RESULTS:The H5N1 NA showed higher activity on α2,3-linked sialic acid than α2,6-linked (P < 0.0001). To compare the NA activity between the H5N1 and seasonal influenza viruses, reverse genetic viruses carrying the NA of H5N1 viruses and NA from a seasonal H3N2 virus was generated. In these reverse genetic viruses, the NA activity of the H5N1 showed markedly higher activity against α2,3-linked sialic acid than that of the H3N2 virus, whereas the activities on α2,6-linkage were comparable. Interestingly, NA from an H5N1 human isolate that was previously shown to have heamagglutinin (HA) with dual specificity showed reduced activity on α2,3-linkage. To confirm the substrate specificity profile, HPLC analytic of enzymatic product was performed. Similar to Amplex red assay, H5N1 virus showed abundant preference on α2,3-linked sialic acid. CONCLUSION:H5N1 virus maintains the avian specific NA and NA changes may be needed to accompany changes in HA receptor preference for the viral adaptation to humans. Key words: H5N1 avian influenza virus; Neuraminidase; Sialic acid; Adaptation; Substrate preference Core tip: We analyzed neuraminidase (NA) substrate specificity of avian influenza H5N1 strains from humans and birds using a modified fluorescence assay, and the substrate specificity profile was further confirmed by Abstract AIM: To characterise neuraminidase (NA) substrate specificity of avian influenza H5N1 strains from humans and birds comparing to seasonal influenza virus. METHODS:Avian influenza H5N1 strains from humans and birds were recruited for characterising their NA substrate specificity by using a modified commercial

show abstract

Section: ��supporting

confidence: 91%

Substrate specificity of avian influenza H5N1 neuraminidase

Onsirisakul

Nakakita

Boonarkart

et al. 2014

WJV

View full text Add to dashboard Cite

show abstract

“…Concerning the releasing effect, NA which mediates the process also has a substrate preference. It was demonstrated that NA of human and swine influenza viruses have a preferential specificity for α2,3-SA although they cleave both linked sialylated glycans [43] , [44] . Therefore, we assume that the sialic acids in respiratory mucus secretions may exert an effect on influenza virus transmission.…”

Section: Discussionmentioning

confidence: 99%

A Beneficiary Role for Neuraminidase in Influenza Virus Penetration through the Respiratory Mucus

et al. 2014

View full text Add to dashboard Cite

Swine influenza virus (SIV) has a strong tropism for pig respiratory mucosa, which consists of a mucus layer, epithelium, basement membrane and lamina propria. Sialic acids present on the epithelial surface have long been considered to be determinants of influenza virus tropism. However, mucus which is also rich in sialic acids may serve as the first barrier of selection. It was investigated how influenza virus interacts with the mucus to infect epithelial cells. Two techniques were applied to track SIV H1N1 in porcine mucus. The microscopic diffusion of SIV particles in the mucus was analyzed by single particle tracking (SPT), and the macroscopic penetration of SIV through mucus was studied by a virus in-capsule-mucus penetration system, followed by visualizing the translocation of the virions with time by immunofluorescence staining. Furthermore, the effects of neuraminidase on SIV getting through or binding to the mucus were studied by using zanamivir, a neuraminidase inhibitor (NAI), and Arthrobacter ureafaciens neuraminidase. The distribution of the diffusion coefficient shows that 70% of SIV particles were entrapped, while the rest diffused freely in the mucus. Additionally, SIV penetrated the porcine mucus with time, reaching a depth of 65 µm at 30 min post virus addition, 2 fold of that at 2 min. Both the microscopic diffusion and macroscopic penetration were largely diminished by NAI, while were clearly increased by the effect of exogenous neuraminidase. Moreover, the exogenous neuraminidase sufficiently prevented the binding of SIV to mucus which was reversely enhanced by effect of NAI. These findings clearly show that the neuraminidase helps SIV move through the mucus, which is important for the virus to reach and infect epithelial cells and eventually become shed into the lumen of the respiratory tract.

show abstract

“…Influenza A viruses of the H1N1 subtype and influenza B viruses have a longer history of circulation among humans than H3N2 viruses. Accordingly, the NAs of these viruses were found to have the same dual substrate specificity as N2-NA of recent human H3N2 isolates [21,22].…”

Section: Studies On Naturally Occurring Virus Isolates: Substrate Spementioning

confidence: 90%

Functional balance between haemagglutinin and neuraminidase in influenza virus infections

Wagner

Matrosovich

Klenk

2002

Reviews in Medical Virology

548

460

View full text Add to dashboard Cite

Influenza A and B viruses carry two surface glycoproteins, the haemagglutinin (HA) and the neuraminidase (NA). Both proteins have been found to recognise the same host cell molecule, sialic acid. HA binds to sialic acid-containing receptors on target cells to initiate virus infection, whereas NA cleaves sialic acids from cellular receptors and extracellular inhibitors to facilitate progeny virus release and to promote the spread of the infection to neighbouring cells. Numerous studies performed recently have revealed that an optimal interplay between these receptor-binding and receptor-destroying activities of the surface glycoproteins is required for efficient virus replication. An existing balance between the antagonistic HA and NA functions of individual viruses can be disturbed by various events, such as reassortment, virus transmission to a new host, or therapeutic inhibition of neuraminidase. The resulting decrease in the viral replicative fitness is usually overcome by restoration of the functional balance due to compensatory mutations in HA, NA or both proteins.

show abstract

Characterization of the hemagglutinin receptor specificity and neuraminidase substrate specificity of clinical isolates of human influenza A viruses

Cited by 12 publications

References 0 publications

Substrate specificity of avian influenza H5N1 neuraminidase

Substrate specificity of avian influenza H5N1 neuraminidase

A Beneficiary Role for Neuraminidase in Influenza Virus Penetration through the Respiratory Mucus

Functional balance between haemagglutinin and neuraminidase in influenza virus infections

Contact Info

Product

Resources

About