Comprehensive studies of drug resistance mediated by overexpression of response regulators of two-component signal transduction systems in Escherichia coli.
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.
Hirakawa
Hidetada
H
Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Japan.
Nishino
Kunihiko
K
Hirata
Takahiro
T
Yamaguchi
Akihito
A
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
D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins