title: The physical demonstration and characterization of extrachromosomal elements.
mesh_terms: D001419:Bacteria / Q000166:cytology*; D002876:Chromosomes, Bacterial; D004269:DNA, Bacterial; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000166:cytology; D005827:Genetics, Microbial; D008722:Methods; D011511:Proteus / Q000166:cytology
chemical_list: D004269:DNA, Bacterial