Quantitative studies on the maturation process of herpes simplex virus type 1 in Vero cells

We examined the time course of viral DNA synthesis, the formation and envelopment of viral nucleocapsids, and the formation of infectious progeny virus in Vero cells infected with herpes simplex virus type 1 (HSV-1). The results showed that the formation of nucleocapsids coincided with the appearance of enveloped particles as well as of infectious progeny virus, although the synthesis of viral DNA took place approximately 2 h prior to the beginning of nucleocapsid formation. These results indicate that the rate-limiting step in the virogenesis of HSV-1-infected cells is the encapsidation of viral DNA and that the enveloped virus is formed immediately after the formation of nucleocapsids and is infectious without any further processing of virion constituents.