title: Electron microscopic studies of replicating and catenated colicin factor E1 DNA isolated from minicells (DNA replication).
abstract: Replicating and catenated DNA molecules of colicin factor E1 that were isolated from minicells were observed by electron microscopy. Two new replicating structures that have been found include: molecules that contain two untwisted replicated branches of the same length and a twisted unreplicated branch, and a twisted circular molecule with a long tail. Other molecular forms identified include circular dimers, three types of catenated dimers (open-open, open-twisted, and twisted-twisted), catenated dimers in which one of the linked molecules is replicating, catenated trimers, and a tetamer.
mesh_terms: D002499:Centrifugation, Density Gradient; D003087:Colicins / Q000032:analysis / Q000302:isolation & purification*; D004261:DNA Replication; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification*; D004926:Escherichia coli / Q000032:analysis; D046911:Macromolecular Substances / Q000032:analysis; D008854:Microscopy, Electron; D008961:Models, Structural; D009690:Nucleic Acid Conformation
chemical_list: D003087:Colicins; D004269:DNA, Bacterial; D046911:Macromolecular Substances