FIG. 7.

Sedimentation analysis of the VP5 hydrophobic point mutants. Vero cell monolayers (10⁷ cells) were infected with KOS, K5R, and the mutant viruses at a multiplicity of infection of 10 PFU/cell and labeled with ³⁵[S]methionine from 8 to 24 h postinfection. Nuclear extracts were prepared and layered onto 20 to 50% sucrose gradients. Following sedimentation, fractions were analyzed by SDS-PAGE (17% acrylamide). The autoradiographs obtained following exposure of the dried gels to X-ray film are shown in the figure. The direction of sedimentation was from right to left. The positions in the gradient where capsids sediment are indicated at the bottom of the panel for KOS and K5R. The positions of the capsid proteins are indicated on the right of each panel except for L75A, for which there was no evident cosedimentation of capsid proteins. Molecular size standards are shown in lane M and are 220, 97.4, 66, 46, 30, and 14.3 kDa.