The presence of two neuraminidases in an influenza virus.
The wild type influenza strain A/Aichi/2/68 (H3N2), when disrupted with SDS and electrophoresed on cellulose acetate paper, yielded two separate neuraminidases, NA(H+) and NA(H-). These enzymes after extraction were biologically active and possessed different specific activities. Enzyme NA(H+) possessed neuraminidase as well as hemagglutinin activities whereas enzyme NA(H-) demonstrated only neuraminidase activity. Similar results were obtained when the Aichi strain was treated with Tween-ether and the two enzymes were separated by affinity chromatography. Techniques used failed to separate the hemagglutinin activity from neuraminidase NA(H+). These results suggest that the dual activity present in enzyme NA(H+) may be characteristic of this protein. Both enzymes are antigenically different and are apparently present as distinct entities in the Aichi strain. Experiments showed that only enzyme NA(H-) of the Aichi strain was incorporated into the hybrid X-32 virus during genetic recombination.
D002846:Chromatography, Affinity; D004588:Electrophoresis, Cellulose Acetate; D000939:Epitopes; D006389:Hemagglutinins, Viral / Q000302:isolation & purification; D009980:Influenza A virus / Q000201:enzymology* / Q000276:immunology; D009439:Neuraminidase / Q000276:immunology / Q000302:isolation & purification*
D000939:Epitopes; D006389:Hemagglutinins, Viral; D009439:Neuraminidase