title: Increased expression of biodegradative threonine dehydratase of Escherichia coli by DNA gyrase inhibitors.
abstract: The synthesis of inducible biodegradative threonine dehydratase of Escherichia coli increased several-fold in the presence of the DNA gyrase inhibitors, nalidixic acid and coumermycin. Temperature-sensitive gyrB mutants expressed higher levels of dehydratase as compared to an isogenic gyrB+ strain. Immunoblotting experiments showed increased synthesis of the dehydratase protein in the presence of gyrase inhibitors; addition of rifampicin and chloramphenicol to cells actively synthesizing enzyme preventing new enzyme production. Increased expression of dehydratase by gyrase inhibitors was accompanied by relaxation of supercoiled DNA.
authors.affiliation: Department of Biological Chemistry, University of Michigan, Ann Arbor 48109-0606.
authors.forename: V N
authors.initials: VN
authors.lastname: Sumantran
authors.forename: A J
authors.initials: AJ
authors.lastname: Tranguch
authors.forename: P
authors.initials: P
authors.lastname: Datta
mesh_terms: D049933:Aminocoumarins; D015153:Blotting, Western; D002701:Chloramphenicol / Q000494:pharmacology; D003374:Coumarins / Q000494:pharmacology; D004250:DNA Topoisomerases, Type II / Q000235:genetics; D004278:DNA, Superhelical / Q000378:metabolism; D004790:Enzyme Induction; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D009154:Mutation; D009268:Nalidixic Acid / Q000494:pharmacology*; D012293:Rifampin / Q000494:pharmacology; D013696:Temperature; D013913:Threonine Dehydratase / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D059005:Topoisomerase II Inhibitors
chemical_list: D049933:Aminocoumarins; D003374:Coumarins; D004278:DNA, Superhelical; D059005:Topoisomerase II Inhibitors; D009268:Nalidixic Acid; D002701:Chloramphenicol; D013913:Threonine Dehydratase; D004250:DNA Topoisomerases, Type II; C004628:coumermycin; D012293:Rifampin