title: Map position of the replication origin on the E. coli chromosome.
abstract: Strains carrying a dnaA temperature sensitive (t.s.) mutation and a Mu-1 prophage inserted within different genes near the origin of replication have been constructed. For each strain, integratively suppressed Hfrs, named G and D in which the ori region was replicated clockwise and counterclockwise respectively, were isolated. The strand preferences of Mu-1 specific Okazaki fragments were subsequently determined for each t.s. strain and its Hfr derivatives. Their comparison led us to establish the direction of replication of the Mu-1 marker from ori. The site ori was confined to the bglB-C--rbsK-P interval.
mesh_terms: D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D003090:Coliphages / Q000235:genetics; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics; D005796:Genes