Fig. 2

Growth curves of the mutants and the WT virus. The growth curve of the mutants was assayed in BHK-21 (A) and U87 cells (B). Viruses were infected in cell monolayers at a MOI of 0.01. Culture supernatants were collected from infected cells at 12 h intervals and were used for the estimation of viral titers in cells. The data are given as means SD from three individual experiments and were tested for significance using a two-way ANOVA with multiple comparison tests. * represents a significant difference between WT and D389H (*, P<0.05;**, P<0.01; ***, P<0.001), ε, between WT and D389S (ε, P<0.05; εε, P<0.01; εεε, P<0.001), δ, between WT and D389G (δ, P<0.05; δδ, P<0.01; δδδ, P<0.001)