title: The effect of nalidixic acid on expression from related E. coli promoters.
abstract: The effect of the DNA gyrase inhibitor, nalidixic acid, on expression from E. coli promoters was studied using the pKO-1, galactokinase expression vector system. Expression from a series of related hybrid promoters, tet promoter variants and the trp promoter flanked by oligonucleotide blocks was measured after incubation with nalidixic acid. Expression from the pBR322 tet promoter and tet promoter mutants within the -10 region was reduced after the drug treatment. The lacUV5, trp, and tettrp promoters were essentially unaffected while the trplac and the trptet promoters were stimulated. Studies of the trp promoter flanked by upstream or downstream oligonucleotide blocks revealed similar responses to the trp promoter parent control plasmids.
mesh_terms: D001483:Base Sequence; D004269:DNA, Bacterial / Q000378:metabolism; D004278:DNA, Superhelical / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics*; D005686:Galactokinase / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects*; D009154:Mutation; D009268:Nalidixic Acid / Q000494:pharmacology*; D010957:Plasmids; D011401:Promoter Regions, Genetic; D059005:Topoisomerase II Inhibitors
chemical_list: D004269:DNA, Bacterial; D004278:DNA, Superhelical; D059005:Topoisomerase II Inhibitors; D009268:Nalidixic Acid; D005686:Galactokinase