title: Coprecipitation of topoisomerase activity with simian virus 40 nucleoprotein complexes by divalent cations.
abstract: Simian virus 40 (SV40) nucleoprotein complexes extracted from nuclei of infected monkey cells (CV1) were precipitated with Ca2+, Mg2+, and Mn2+ divalent cations. Most of the viral chromatin but only a fraction of the proteins in the crude nuclear extracts were recovered after precipitation with 10 mM MgCl2. At this optimal concentration, DNA topoisomerase activity (nicking closing enzyme) coprecipitated with the SV40 nucleoprotein complexes.
authors.affiliation: Département de Biologie moléculaire, Institut Pasteur, 75724 Paris Cedex 15, France.
authors.forename: C
authors.initials: C
authors.lastname: Hamelin
authors.forename: M
authors.initials: M
authors.lastname: Yaniv
mesh_terms: D000818:Animals; D001671:Biochemistry / Q000379:methods*; D002118:Calcium / Q000737:chemistry; D002122:Calcium Chloride / Q000494:pharmacology; D002412:Cations; D002467:Cell Nucleus / Q000378:metabolism / Q000821:virology; D002522:Chlorocebus aethiops; D002843:Chromatin / Q000378:metabolism; D026942:DNA Topoisomerases / Q000737:chemistry*; D004264:DNA Topoisomerases, Type I / Q000737:chemistry / Q000378:metabolism; D008274:Magnesium / Q000737:chemistry; D008345:Manganese / Q000737:chemistry; D009698:Nucleoproteins / Q000737:chemistry*; D011485:Protein Binding; D013539:Simian virus 40 / Q000378:metabolism*
chemical_list: D002412:Cations; D002843:Chromatin; D009698:Nucleoproteins; D008345:Manganese; D026942:DNA Topoisomerases; D004264:DNA Topoisomerases, Type I; D008274:Magnesium; D002122:Calcium Chloride; D002118:Calcium