title: Characterization of human cytomegalovirus-induced DNA polymerase and the associated 3'-to-5', exonuclease.
abstract: A DNA polymerase activity induced by human cytomegalovirus (HCMV) was separated from host cell DNA polymerase and purified by phosphocellulose and DNA-cellulose column chromatography. The DNA polymerase activity was strongly inhibited by phosphonoacetic acid, aphidicolin, araATP, and N-ethylmaleimide, but it was resistant to 2',3'-dideoxyTTP. The sensitivity of HCMV-induced DNA polymerase to these reagents resembles that of host cell DNA polymerase alpha. However, HCMV-induced DNA polymerase activity was stimulated several fold by 100 mM ammonium sulfate, by which DNA polymerase alpha activity was strongly inhibited. Furthermore, it was found that a 3'-to-5' exonuclease activity was tightly associated with the HCMV-induced DNA polymerase. The exonuclease was also stimulated by ammonium sulfate, was inhibited by phosphoacetic acid, and it preferred single-stranded DNA as a substrate. The results suggest that the 3'-to-5' exonuclease may play a role in proofreading in the polymerization process as an integral part of the HCMV-induced DNA polymerase.
mesh_terms: D000645:Ammonium Sulfate / Q000494:pharmacology; D016590:Aphidicolin; D003587:Cytomegalovirus / Q000201:enzymology*; D004277:DNA, Single-Stranded / Q000378:metabolism; D004259:DNA-Directed DNA Polymerase / Q000302:isolation & purification / Q000378:metabolism*; D004224:Diterpenes / Q000494:pharmacology; D005033:Ethylmaleimide / Q000494:pharmacology; D043211:Exodeoxyribonuclease V; D005090:Exodeoxyribonucleases / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010746:Phosphonoacetic Acid / Q000494:pharmacology; D013379:Substrate Specificity; D001084:Vidarabine Phosphate / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D004277:DNA, Single-Stranded; D004224:Diterpenes; D001084:Vidarabine Phosphate; C000101:ara-ATP; D016590:Aphidicolin; D004259:DNA-Directed DNA Polymerase; D005090:Exodeoxyribonucleases; D043211:Exodeoxyribonuclease V; D010746:Phosphonoacetic Acid; D005033:Ethylmaleimide; D000645:Ammonium Sulfate