[pH-dependent hemolytic and neuraminidase activity of remantadine-sensitive and -resistant variants of influenza virus].

A comparative study of pH-dependence of hemolytic and neuraminidase activities of four remantadin-sensitive influenza A virus strains CAPV (classical avian plague virus) (H7N7), USSR/090/77 (H1N1), Ann Arbor (H2N2), and Texas (H3N2) and their remantadin-resistant variants was carried out. The original strains were shown to produce hemolysis in a narrow pH range (5.0 and 5.5) and to have maximal neuraminidase activity at the same pH values. In remantadin-resistant variants the optimal pH values for hemolytic and neuraminidase activities were higher by 0.5-1.0 than for the sensitive variants.