title: Human cytomegalovirus-associated DNA polymerase and protein kinase activities.
abstract: Human cytomegalovirus (HCMV), purified exclusively from the extracellular media, contained a DNA polymerase activity in addition to a protein kinase activity. The DNA polymerase expressed its maximum activity in the presence of 5 to 10 mM-MgCl2. The enzyme was able to use effectively activated calf thymus DNA, poly(dA).oligo(dT)12--18 and poly(dC).oligo(dG)12--18 as the template primers. The DNA polymerizing activity was eluted with 0.18 to 0.2 M-KCl from a phosphocellulose column. It was relatively resistant to phosphonoacetic acid inhibition even at a high concentration of 100 micrograms/ml with activated calf thymus DNA as the template primer, but the DNA polymerase activity was totally suppressed at this concentration when poly(dA).oligo(dT)12--18 was used as the template primer. The enzyme activity was inhibited by ammonium sulphate at 0.01 to 0.3 M with either activated calf thymus DNA or poly(dA).oligo(dT)12--18 as the template primer. The protein kinase has maximum activity in the presence of 10 to 20 mM-MgCl2, and preferred virion proteins as phospho-acceptor to protamine sulphate. Histone, caesin and bovine serum albumin (BSA) were found to be poor substrates. The phosphorylated protein pattern of the in vivo [32P]orthophosphate-labelled virions was not identical to that of the in vitro phosphorylated Nonidet P40-dissociated virions, although seven phosphorylated polypeptides did co-migrate in SDS--polyacrylamide gel electrophoresis (SDS--PAGE). Procedures known to solubilize virions showed that the DNA polymerase and protein kinase were internal components of the virion.
mesh_terms: D000645:Ammonium Sulfate / Q000494:pharmacology; D003587:Cytomegalovirus / Q000201:enzymology*; D004247:DNA / Q000378:metabolism; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D006801:Humans; D008274:Magnesium / Q000378:metabolism; D015636:Magnesium Chloride; D010746:Phosphonoacetic Acid / Q000494:pharmacology; D011089:Polydeoxyribonucleotides / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism*; D013379:Substrate Specificity; D013698:Templates, Genetic
chemical_list: D011089:Polydeoxyribonucleotides; D015636:Magnesium Chloride; D004247:DNA; D011494:Protein Kinases; D004259:DNA-Directed DNA Polymerase; D008274:Magnesium; D010746:Phosphonoacetic Acid; D000645:Ammonium Sulfate