FIG. 6.

Analysis of the structures produced by BacΔIBDA-DEDLE5A. Sf9 cells were infected with BacΔIBDA-DEDLE5A for treatment with Freon 113 as described in Materials and Methods. After 18 h of centrifugation in a CsCl density of 1.30 at 35,000 rpm, the gradient were illuminated with white light and photographed (A). Material collected from the bands present in the gradients was negatively stained with 2% uranyl acetate. Large numbers of VLPs were observed in the lower band, whereas tubes were mainly observed in the upper band. The bar represents 0.2 μm. (B) SDS-PAGE analysis and Coomassie blue staining of purified IBDV and of the material present in the lower and upper bands. (C) Western blot analyses of purified virus and of the material present in the lower and in the upper bands with an anti-pVP2/VP2 antibody or with an anti-VP3 antibody. The relative molecular weights (in thousands), determined by reference to marker proteins, are indicated on the left.