Role of rpoS (katF) in oxyR-independent regulation of hydroperoxidase I in Escherichia coli.
We present evidence showing that rpoS (katF) is a regulator of katG gene transcription in an oxyR-independent manner. Mutation of the rpoS gene in several different Escherichia coli strains caused a significant reduction in catalase HPI activity. In rpoS-delta oxyR double mutants, the level of HPI was considerably lower compared to the delta oxyR parent strain, and was restored when transformed with an rpoS+ plasmid. Overproduction of HPI in oxyR- suppressor strains was greatly diminished after inactivation of the rpoS gene and was accompanied by a substantial increase in sensitivity to menadione. Beta-galactosidase expression from a katG::lacZ promoter was lower in rpoS strains compared to rpoS+ isogenic parents. Several delta oxyR strains had detectable levels of katG transcription that was significantly diminished after rpoS gene inactivation.
Ivanova
A
A
Cancer Research Center, Columbia, Missouri 65201.
Miller
C
C
Glinsky
G
G
Eisenstark
A
A
D002374:Catalase / Q000235:genetics*; D004352:Drug Resistance, Microbial / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D016153:Genes, Suppressor; D007763:Lac Operon; D009154:Mutation; D014158:Transcription, Genetic; D014812:Vitamin K / Q000494:pharmacology
D029968:Escherichia coli Proteins; D014812:Vitamin K; D002374:Catalase; C051253:katG protein, E coli