期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1971
卷号：68
期号：10
页码：2574-2578
DOI：10.1073/pnas.68.10.2574
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：When purified polyoma virus is exposed to 0.01 M dithiothreitol in the presence of 0.2 M Na2CO3-NaHCO3 (pH 10.6) at 0-4{degrees}C, the capsids are rapidly disrupted to protein subunits of capsomere size, as judged by density gradient centrifugation, sedimentation equilibrium centrifugation, and electron microscopy. Hemagglutination activity and infectivity of disrupted virus are reduced to below detectable amounts. Removal of the disruption reagents by dialysis at 4{degrees}C against 0.05 M Tris-0.14 M NaCl-1 mM EDTA and 0.1 mM 2-mercaptoethanol (pH 8.0) results in a time-dependent reappearance of up to 17% of the starting hemagglutination titer, under optimum conditions of ionic strength, pH, temperature, and virus protein concentration. The recovered hemagglutination activity is found in glycerol gradients associated with a 100S DNA-protein complex consisting mostly of linear aggregates of capsomeres. When the linear complex is treated with pancreatic DNase, the complex is converted into spherical particles, of approximately virus size, that sediment at 140 S (with aggregates at 180 S), as well as on the cushion of half-saturated CsCl at the bottom of the gradients. All reassembled particles are not infectious and have markedly reduced DNA to protein ratios.
关键词：hemagglutination ; infectivity ; electron microscopy ; density-gradient centrifugation
