title: Comprehensive studies of drug resistance mediated by overexpression of response regulators of two-component signal transduction systems in Escherichia coli.
abstract: In Escherichia coli, there are 32 open reading frames (ORFs) that are assumed to be response regulator genes of two-component signal transduction systems on the basis of sequence similarities. We cloned all of these 32 ORFs into a multicopy expression vector and investigated whether or not they confer drug resistance via control of drug resistance determinants. Fifteen of these ORFs, i.e., baeR, citB, cpxR, evgA, fimZ, kdpE, narL, narP, ompR, rcsB, rstA, torR, yedW, yehT, and dcuR, conferred increased single- or multidrug resistance. Two-thirds of them conferred deoxycholate resistance. Five of them, i.e., evgA, baeR, ompR, cpxR, and rcsB, modulated the expression of several drug exporter genes. The drug resistance mediated by evgA, baeR, and cpxR could be assigned to drug exporters by using drug exporter gene knockout strains.
authors.affiliation: Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Japan.
authors.forename: Hidetada
authors.initials: H
authors.lastname: Hirakawa
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Nishino
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hirata
authors.forename: Akihito
authors.initials: A
authors.lastname: Yamaguchi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005809:Genes, Regulator / Q000502:physiology*; D008826:Microbial Sensitivity Tests; D016366:Open Reading Frames / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction; D014158:Transcription, Genetic
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins