title: Unidirectional replication of plasmid ColE1 DNA.
mesh_terms: D002499:Centrifugation, Density Gradient; D003087:Colicins / Q000096:biosynthesis*; D004261:DNA Replication; D004269:DNA, Bacterial / Q000096:biosynthesis* / Q000302:isolation & purification; D004720:Endonucleases / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D005111:Extrachromosomal Inheritance; D006868:Hydrolysis; D013936:Thymidine / Q000378:metabolism; D013941:Thymine / Q000378:metabolism; D014316:Tritium
chemical_list: D003087:Colicins; D004269:DNA, Bacterial; D014316:Tritium; D004720:Endonucleases; D013941:Thymine; D013936:Thymidine