Fig. 4

DNase I footprints of PhaR on the phaP1 (a) and phaP4 (b) promoter regions. DNaseI footprints of PhaR-His₆ binding found in DNA fragment patterns are shown for the phaP1 (a) and phaP4 (b) promoter regions; the fragment patterns on upper and lower strands are in the left and right side of each panel, respectively. Each of the panels contain four fragment charts for respective upper and lower strands; from the top to down, the first is the sequencing ladders in four colors, the second is the negative control without PhaR-His₆, and the third and fourth are the two different concentrations of PhaR-His₆ as indicated. At the bottom of each panel, nucleotide sequences of the promoter regions of phaP1 (a) and phaP4 (b) are shown. The sequence stretches protected from DNase I digestion by PhaR-His₆ binding are shown in hatched squares. Hocked arrowheads and the labels “+ 1” indicate the transcriptional start point (shown in blue letters in the upper strands). The −35 and − 10 regions are underlined and the ATG initiating codons are shown in red letters in the upper strands