[Density gradient and ultrastructure of bovine adenovirus type 1]

Isolated and purified were virions and hexones from the bovine adenovirus type 1. The infectious virions were of equilibrium density of 1.34 g/cm3, and the empty capsids--of 1.305 g/cm3. The virions had a facet length of 43.5 nm, their size being 82.7 nm (distance between opposite poles) to 74.0 nm (diameter of the virion). The fibers of the bovine adenovirus type 1 measured 26.0--28.0 nm. The virus was destroyed by 30 per cent formamide, yielding free hexones of 1.290 g/cm3 of equlibrium density. The hexones were 10.0-12.0 nm high, were thicker at their base, and possessed a central cavity. Beside single hexones groups of 9 hexones each were also found in the soluble components (being of a left and a right type according to the arrangement of the capsomeres in them). It was demonstrated serologically that the hexones possessed 2 antigen determinants which retained their antigenic activity even after the hexones degraded and lost their morphologic type.