FIG. 1.

SDS-PAGE analysis of HSV-1 in vitro tegument release assay. wt (A) and UL13 mutant (B) viruses were detergent treated and incubated at 37°C for 30 min in the presence or absence of 1 mM ATP and/or 1 mM magnesium chloride. They were then fractionated via sucrose gradient centrifugation into pelleted (P) or released (R) material. These samples were analyzed by SDS-PAGE, and the gels were stained with Coomassie blue to visualize total protein. Note in both viruses the partitioning of the major capsid protein VP5 into the pelleted fraction and of the major glycoproteins (glyco) into the soluble fraction, demonstrating effective fractionation. The major tegument proteins were identified by MW, indicated on the right in kilodaltons. VP1/2 was detected only in the pelleted material. The amount of VP13/14 in the released fraction of both viruses was increased by incubation with ATP and Mg in combination but not individually.