title: Phosphorylation of acyclovir in vitro in activated Burkitt somatic cell hybrids.
abstract: Acyclovir [9-(2-hydroxyethoxymethyl)guanine] (ACV), a potent antiviral compound, was phosphorylated to the same extent by extracts from untreated and iododeoxyuridine-treated Epstein-Barr virus-containing latent D98/HR-1 somatic hybrid cells. ATP was the preferred phosphate donor over other nucleoside triphosphates. The cytosol extract from D98/HR-1 cells effected optimum phosphorylation of thymidine at pH 8.0, whereas ACV was phosphorylated equally well over a wide pH range. Electrophoretic analysis of thymidine kinase-, deoxycytidine kinase-, and ACV-phosphorylating activities from both untreated and iododeoxyuridine-treated cell extracts displayed identical properties. A small part (5 to 10%) of the loaded ACV-phosphorylating activity seemed to migrate with the deoxycytidine kinase activity from cytosol. dTTP and dCTP, at relatively high concentrations, partially inhibited ACV-phosphorylating activity. The results suggest that Epstein-Barr virus does not code for its own thymidine kinase and that phosphorylation of ACV in Epstein-Barr virus-producing cells is carried out by multiple or as yet unidentified ATP-dependent nonspecific cellular phosphotransferases.
mesh_terms: D000212:Acyclovir / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004854:Herpesvirus 4, Human; D006822:Hybrid Cells / Q000378:metabolism; D007065:Idoxuridine / Q000494:pharmacology; D007700:Kinetics; D010766:Phosphorylation; D013936:Thymidine / Q000378:metabolism
chemical_list: D007065:Idoxuridine; D013936:Thymidine; D000212:Acyclovir