title: Red cells bound to influenza virus N9 neuraminidase are not released by the N9 neuraminidase activity.
abstract: Influenza virus neuraminidase (NA) of the N9 subtype also possesses hemagglutinin activity and the hemagglutinating, or hemabsorbing (HB), site is distinct from the catalytic site. Previous results suggested that the NA was binding to sialic acid on the red cell surface, but we now report that the HB receptor is not sensitive to N9 influenza neuraminidase activity. Cell lines that constitutively express N9 or N2 neuraminidase have been used to further investigate the specificity of red blood cell binding to the HB site. The results suggest that the ligand is N-acetylneuraminic acid in a linkage or environment that is not sensitive to influenza virus neuraminidase, but which is released by the broadly specific bacterial sialidases from Micromonospora viridifaciens or Arthrobacter ureafaciens.
authors.affiliation: Department of Microbiology, University of Alabama at Birmingham 35294, USA.
authors.forename: G M
authors.initials: GM
authors.lastname: Air
authors.forename: W G
authors.initials: WG
authors.lastname: Laver
mesh_terms: D000818:Animals; D016466:CHO Cells; D002460:Cell Line; D002645:Chickens; D006224:Cricetinae; D004912:Erythrocytes / Q000276:immunology* / Q000821:virology; D006389:Hemagglutinins, Viral / Q000276:immunology*; D006801:Humans; D009439:Neuraminidase / Q000145:classification / Q000276:immunology*; D009975:Orthomyxoviridae / Q000201:enzymology / Q000276:immunology*
chemical_list: D006389:Hemagglutinins, Viral; D009439:Neuraminidase