OtcR directly activates the transcription from
. A. An illustration of the reporter plasmids. B. Detection of the regulatory relationship of OtcR and oxy promoters using gfp reporter plasmids in E.coli. C. Sequences of the direct repeats of native oxyI promoter (PoxyI) and two mutants (PoxyI1* and PoxyI2*). D. Detection of the interaction of OtcR with the direct repeat sequences of PoxyI, PoxyI1* and PoxyI2* using gfp reporters. The values are means ± SD from three independent experiments.