Synthesis of herpes simplex virus DNA in isolated chromatin

Herpes simplex virus DNA synthesis was studied in isolated chromatin (HSV chromatin) of African green monkey kidney (RC-37) cells after HSV type 1 infection. After optimizing the in vitro system, HSV chromatin was shown to synthesize both viral and cellular DNA at ratios identical with those seen in vivo. After 30 min of DNA synthesis in vitro, the DNA products were identical in size to the prelabeled parental DNA. More than 60% of the newly synthesized single-stranded DNA fragments sedimented with a sedimentation constant of greater than 10 S. HSV DNA polymerase was found to be responsible for the synthesis of 80% of all in vitro made viral and most likely also cellular DNA sequences.