Effects of cytosine arabinoside on the incorporation of pyrimidine nucleosides into hamster cells transformed by herpes simplex type 1 and type 2 viruses and by human cytomegalovirus.

The incorporation of 3H-thymidine and 3H-deoxycytidine into acidoprecipitable fraction of hamster cells transformed by herpes simplex viruses type 1 and type 2 and of 3H-thymidine into hamster cells transformed by human cytomegalovirus was found to be resistant to the action of cytosine arabinoside. More 3H-thymidine was incorporated into these cells in the presence than in the absence of the drug. Similar stimulaton of 3H-thymidine uptake could be achieved by using unlabelled deoxycytidine instead of cytosine arabinoside.

Syntheses of virus-induced thymidine kinase and viral DNA in herpes simplex type 1 virus-infected chick embryo fibroblasts.

Herpes simplex virus type 1, strain Kupka, did not replicate in chick embryo fibroblasts (CEF), but the infection was followed by the development of cytopathic changes. This effect could be abolished by UV irradiation of the virus. Virus-induced thymidine kinase was synthesized in the infected cells reaching a maximum level at 24 hours post infection (p.

Thymidine-kinase in cytomegalovirus infected cells.

In human diploid fibroblast LEP cells infected with AD169 strain of human cytomegalovirus (CMV) a sharp increase of cytosol thymidine kinase activity was observed. The properties of the cytosol enzymes from infected and non-infected cells were compared. No significant differences between the enzymes from infected and control cells were observed in substrate specificity, pH dependence, thermostability and relative electrophoretic mobility.