Complete Nucleotide Sequence of the Escherichia coli Plasmid pBR322

Excerpt

I have determined the 4362-nucleotide-pair sequence of the plasmid cloning vector pBR322 using the DNA-sequencing technique of Maxam and Gilbert (1977). The DNA structure has several interesting features that lead to testable predictions.

pBR322 contains DNA segments assembled in vitro from three naturally occurring plasmids (Bolivar et al. 1977c). The tetracycline resistance (Tc^r) phenotype derives from a fragment of the Salmonella plasmid pSC101 (Cohen and Chang 1977). The ampicillin resistance gene (amp^r) comes from the Tn3 transposon originally carried by the S. paratyphi B plasmid R7268 (later known as R1drd19) (Datta and Kontomichalou 1965; Meynell and Datta 1967). The replicator region is derived from pMB1, an Escherichia coli plasmid bearing the genes for ColE1, colicin immunity, and the EcoRI restriction and modification enzymes (Betlach et al. 1976). Plasmid pMB1 appears to be related to the extensively studied plasmid ColE1; both plasmids replicate in the relaxed mode, require both RNA polymerase...