Chromosome Replication in Escherichia coli Is Inhibited in the Terminus Region near the rac Locus

The circular chromosome of Escherichia coli is replicated in a bidirectional fashion (Masters and Broda 1971; Bird et al. 1972; Prescott and Kuempel 1972; Hohlfeld and Vielmetter 1973; Rodriguez et al. 1973), and the origin of replication is located at 83 minutes on the genetic map (Yasuda and Hirota 1977). After initiation, the two replication forks travel at similar rates in opposite directions around the chromosome (Kuempel et al. 1973b) and meet at the replication terminus (Kuempel et al. 1973a). The replication terminus is located opposite the origin of replication on the circular chromosome (Rodriguez et al. 1973), between the his and trp loci (Bird et al. 1972; Hohlfeld and Vielmetter 1973).