Proteins specified by herpes simplex virus. 8. Characterization and composition of multiple capsid forms of subtypes 1 and 2.

Two classes of herpesvirus capsids, designated A and B, were isolated from the nuclei of human cells infected with herpes simplex virus (HSV). A and B capsids share in common four structural proteins, i.e., no. 5, 19, 23, and 24. B capsids contain 7.7 to 9.7 times more deoxyribonucleic acid than A capsids; moreover, they contain proteins no. 21 and 22a in addition. All of the proteins contained in the capsid except no. 22a are present in the enveloped nucleocapsids (virions) in approximately the same molar ratios. The capsid proteins of HSV-1 cannot be differentiated from their HSV-2 counterparts with respect to electrophoretic mobility. A third class of capsids, designated C capsids, was isolated from virions contained in the cytoplasm of infected cells by the same procedure used to obtain A and B capsids. The C capsids contain all of the proteins present in A capsids plus proteins 1 to 3 and 21.