Density differences between hybrid and nonhybrid particles in two adenovirus-simian virus 40 hybrid populations.

The adenovirus 7-simian virus 40 hybrid virus population E46(+) was subjected to fixed-angle equilibrium density gradient centrifugation in CsCl. A difference in buoyant density between the hybrid virion and its nonhybrid adenovirus 7 counterpart was noted, the hybrid virion possessing the lower buoyant density. This difference in buoyant density appeared to be accentuated in a population of adenovirus 2(+t7), a derivative of E46(+) in which the adenovirus 7-simian virus 40 genome had been transferred to an adenovirus 2 capsid.