Structural evidence for a second sialic acid binding site in avian influenza virus neuraminidases.
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ABSTRACT:
SUBMITTER: Varghese JN
PROVIDER: S-EPMC23599 | biostudies-literature | 1997 Oct
REPOSITORIES: biostudies-literature
Publications
Structural evidence for a second sialic acid binding site in avian influenza virus neuraminidases.
Varghese J N JN Colman P M PM van Donkelaar A A Blick T J TJ Sahasrabudhe A A McKimm-Breschkin J L JL
Proceedings of the National Academy of Sciences of the United States of America 19971001 22
The x-ray structure of a complex of sialic acid (Neu5Ac) with neuraminidase N9 subtype from A/tern/Australia/G70C/75 influenza virus at 4 degrees C has revealed the location of a second Neu5Ac binding site on the surface of the enzyme. At 18 degrees C, only the enzyme active site contains bound Neu5Ac. Neu5Ac binds in the second site in the chair conformation in a similar way to which it binds to hemagglutinin. The residues that interact with Neu5Ac at this second site are mostly conserved in av ...[more]
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