ABSTRACT
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. Incorporation of both nucleosides into spontaneously and SV40 transformed cells was efficiently inhibited by the drug.
Subject(s)
Cell Transformation, Viral , Cytarabine/pharmacology , Cytomegalovirus/physiology , Pyrimidine Nucleosides/metabolism , Simplexvirus/physiology , Animals , Cell Line , Cricetinae , Deoxycytidine/metabolism , Deoxycytidine/pharmacology , Humans , Phosphorylation , Thymidine/metabolismABSTRACT
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.i.). In the presence of cytosine arabinoside, thymidine kinase synthesis was enhanced. This suggested that the late (post-replicative) viral function, which turns off thymidine kinase synthesis, was expressed in the infected CEF untreated with the drug. HSV type 1 laboratory strains Kupka and KOS were capable of inducing the synthesis of virus-specific DNA in CEF. But in CEF infected with fresh type 1 virus isolates replication of viral DNA was not observed.
Subject(s)
DNA, Viral/biosynthesis , Simplexvirus/metabolism , Thymidine Kinase/biosynthesis , Animals , Cell Line , Chick Embryo , Cytarabine/pharmacology , Cytopathogenic Effect, Viral , Enzyme Induction , Fibroblasts , Simplexvirus/enzymology , Simplexvirus/growth & developmentABSTRACT
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. Human sera containing high titres of CMV complement-fixing antibodies did not neutralize the enzyme from infected cells. It is concluded from these results that the increase of cytosol thymidinekinase activity in CMV-infected cells was due to an enhancement of cellular thymidine kinase.
Subject(s)
Cytomegalovirus/growth & development , Thymidine Kinase/metabolism , Antibodies, Viral , Cell Line , Cytomegalovirus Infections/immunology , Cytosol/enzymology , Hot Temperature , Humans , Hydrogen-Ion Concentration , Phosphotransferases/metabolism , Thymidine Kinase/immunologySubject(s)
Coliphages , Conjugation, Genetic , Embryo Implantation , Mutation , Coliphages/immunology , Escherichia coli/immunology , Female , Lysogeny , StreptomycinSubject(s)
Coliphages/metabolism , DNA, Viral , Recombination, Genetic , Adsorption , Ammonium Sulfate , Cell-Free System , Chemical Precipitation , Chromosomes, Bacterial , Coliphages/enzymology , DNA, Viral/isolation & purification , Endonucleases/metabolism , Escherichia coli/enzymology , Genes , Hot Temperature , In Vitro Techniques , Lysogeny , Micropore Filters , Phosphorus IsotopesSubject(s)
Chromosome Aberrations , Chromosomes, Bacterial , Chromosome Mapping , Coliphages , Escherichia coli , Kinetics , Lysogeny , Transduction, GeneticSubject(s)
Coliphages/isolation & purification , Bacteriolysis , Calcium Phosphates , Chromatography , Escherichia coli , MethodsABSTRACT
The gal-bio region was transduced from Escherichia coli B to K12 and lysogenized with lambda b2. By means of P1 transduction mapping, the lambda b2 prophage was shown to be inserted between gal and bio and to be circularly permuted in the same way as lambda b2+ in K12. Increased frequency of recombinations within the prophage was observed when the viral genes were mapped with respect to bio instead of to gal. The results are interpreted to indicate the existence of a region in lambda situated close to the b2 region and homologous with a lambda attachment site of E. coli B but not with that of E. coli K12.
