Proteins of herpesvirus type 2: I. Virion, nonvirion, and antigenic polypeptides in infected cells.

Purified herpesvirus type 2 (HSV-2 (G)) virions were prepared by two cycles of centrifugation on dextran T-10 gradients from cytoplasmic extracts of infected human epidermoid carcinoma (HEp-2) cells. The purity of the preparation was assessed by electron microscopy and by an analysis of the ratio of infectivity to trichloroacetic acid-precipitable counts. The extent of purification by the latter criterion was at least 240-fold with respect to host proteins. Sodium dodecyl sulfate-acrylamide-gel electrophoresis of the proteins from these virion preparations revealed the existence of a minimum of 24 proteins. Forty-seven viral proteins were identified in HSV-2 (G) infected HEp-2 cells by using one or more of the following criteria: (i) an increased rate of synthesis following infection; (ii) precipitation by antisera specific for viral antigens; and (iii) variations in their electrophoretic mobilities or rates of synthesis following infection with different strains of HSV-2. Twenty-four of these viral proteins have electrophoretic mobilities similar to those of the proteins prepared from purified virions. The remaining 23 viral proteins were classified as nonstructural proteins. The 47 viral proteins could be subclassified into four groups on the basis of their kinetics of synthesis, indicating regulation of the amounts of viral protein synthesized. The data are discussed in terms of their relevance to the molecular aspects of productive HSV-2 infection and to the identification of the viral antigens responsible for stimulating the production of neutralizing and complement-fixing antibodies.