title: Molecular cloning and characterization of the purE operon of Escherichia coli.
abstract: The purE operon of Escherichia coli has been cloned and localized to a 1.7-kb HpaI fragment. The operon has been further characterized by subcloning into the lac fusion vector, pMC1403, and by the construction of BAL 31-generated deletions. The purE regulation region has been identified by assay of beta-galactosidase produced by pur-lac fusion plasmids and by RNA polymerase binding to end-labelled restriction fragments. Two purE promoters have been identified; one strong that is regulated by purines, the other weaker which is not regulated. The latter may be internal to the purE1 structural gene.
mesh_terms: D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D005822:Genetic Vectors; D009876:Operon; D010957:Plasmids; D011401:Promoter Regions, Genetic; D001616:beta-Galactosidase / Q000235:genetics
chemical_list: D012321:DNA-Directed RNA Polymerases; D004262:DNA Restriction Enzymes; D001616:beta-Galactosidase