[Role of carbohydrates in the manifestation of the hemagglutinating and neuraminidase activities of the influenza virus].

Suspensions of influenza virions (MRC-11, X-7, and A/PR8/34 strains) were treated with a mixture of glycosidases including alpha-D-mannosidase, alpha-L-fucosidase, beta-D-galactosidase, and beta-D-N--acetylglucosaminidase for the study of the influence of carbohydrate part of influenza virus surface glycoproteins on the hemagglutinating and neuraminidase activity. The availability of oligosaccharide chains for the effect of glycosidases was found to change in relation to the functional status of the glycoprotein molecule. When carbohydrate residues were cleaved from neuraminidase in virus particle, its enzymatic activity did not change, whereas the hemagglutinating activity of virions after treatment with glycosidases decreased more than 50-fold.