Osmoregulatory expression of the ompC gene in Escherichia coli K-12; IS1 insertion in the upstream regulatory region results in constitutive activation of the promoter.
A novel type of osmoregulatory mutant of Escherichia coli K-12 exhibiting constitutive expression of the ompC gene was isolated and characterized at the molecular level. In this particular mutant (cec; constitutive expression of OmpC), an insertion sequence (IS-1) was found to be located at right upstream of the regulatory sequence for the ompC promoter. We demonstrate that the IS1 insertion observed in the cec mutant does not provide the ompC gene with an artificial promoter, but rather perturbs normal regulation of the ompC promoter, which is mediated by the regulatory gene, ompR.
Ozawa
Y
Y
Laboratory of Microbiology, School of Agriculture, Nagoya University, Japan.
Mizushima
S
S
Mizuno
T
T
D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001483:Base Sequence; D004251:DNA Transposable Elements; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D008969:Molecular Sequence Data; D009154:Mutation; D018272:Porins; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D014158:Transcription, Genetic; D014882:Water-Electrolyte Balance
D001425:Bacterial Outer Membrane Proteins; D004251:DNA Transposable Elements; D018272:Porins