title: Structure and function of the polypeptides in simian virus 40. I. Existence of subviral deoxynucleoprotein complexes.
abstract: Velocity sedimentation analysis of simian virus 40 degraded in alkaline buffers, pH 10.5, yields two components: soluble protein containing the largest polypeptides, VP1 and VP2, of the virion, and a deoxynucleoprotein complex (DNP-I) containing the viral deoxyribonucleic acid (DNA) and the small polypeptides, VP4, 5, and 6, and all or part of VP3. Dissociation of DNP-I by equilibrium centrifugation in CsCl yields a complex (DNP-II) of the viral DNA and residual, tightly bound polypeptide; VP4, 5, and 6, but not VP3, are recovered after separation from DNP-II. Treatment of the virus with beta-mercaptoethanol and iodination experiments suggest that VP1 and VP2 might exist as compact structures cross-linked with disulfide bonds, perhaps forming the capsid. VP4, 5, and 6 form a relatively stable complex with the viral DNA and are supposed to be the internal proteins. The location of VP3 is not well defined; at least a portion of it is tightly bound to the viral DNA.
mesh_terms: D000085:Acetates; D000596:Amino Acids; D000818:Animals; D001345:Autoradiography; D001665:Binding Sites; D002247:Carbon Isotopes; D002460:Cell Line / Q000382:microbiology; D002499:Centrifugation, Density Gradient; D004279:DNA, Viral / Q000032:analysis; D004589:Electrophoresis, Disc; D000882:Haplorhini; D007455:Iodine; D007668:Kidney; D008623:Mercaptoethanol; D008854:Microscopy, Electron; D009698:Nucleoproteins / Q000032:analysis*; D010455:Peptides / Q000032:analysis*; D013539:Simian virus 40 / Q000032:analysis* / Q000254:growth & development / Q000302:isolation & purification; D013194:Staining and Labeling; D013936:Thymidine; D014316:Tritium; D014501:Uranium; D014764:Viral Proteins / Q000032:analysis*
chemical_list: D000085:Acetates; D000596:Amino Acids; D002247:Carbon Isotopes; D004279:DNA, Viral; D009698:Nucleoproteins; D010455:Peptides; D014764:Viral Proteins; D014316:Tritium; D014501:Uranium; D008623:Mercaptoethanol; D007455:Iodine; D013936:Thymidine