title: Characterization of deoxyribonucleic acid from Yersinia pestis by ethidium bromide-cesium chloride density gradient centrifugation.
abstract: No plasmids were detected in cells of Yersinia pestis which were bacteriocinogenic and positive for three additional determinants of virulence known to be lost at high frequency.
mesh_terms: D002499:Centrifugation, Density Gradient; D002586:Cesium; D002712:Chlorides; D004269:DNA, Bacterial / Q000032:analysis*; D004996:Ethidium; D005111:Extrachromosomal Inheritance; D005827:Genetics, Microbial; D013696:Temperature; D013936:Thymidine / Q000378:metabolism; D014316:Tritium; D014774:Virulence; D015010:Yersinia pestis / Q000032:analysis*
chemical_list: D002712:Chlorides; D004269:DNA, Bacterial; D014316:Tritium; D002586:Cesium; D004996:Ethidium; D013936:Thymidine