FIG. 5.

Regulatory elements of the ulaA-G regulon. (A) Sequence of the ulaA-G intergenic region. The directions of the ulaA and ulaG open reading frames (ORF) are indicated by dotted arrows. Predicted ATG start codons are indicated by bold type, and the corresponding ribosome binding sites (RBS) are also indicated. The IHF, cAMP-CRP, and UlaR binding sites are indicated by shading. The inverted repeat of the UlaR operator sites is indicated by asterisks. (B) Diagram showing the locations of the putative IHF, CRP, and UlaR binding sites (open boxes) between the ulaA and ulaG genes (gray arrows) and the fragments used as probes in the gel shift experiments (lines). (C) UlaR binding to probes P193 and P238 in the presence of different concentrations of l-ascorbate-6-phosphate (Asc-6P). A control lane with no protein was also included. (D) Complexes of P238 with no protein (lane 1), with 10 μg of crude extract of K. pneumoniae strain ATCC 13882 (lane 2), with 10 μg of crude extract of E. coli strain JA134 (lane 3), with 10 μg of crude extract of E. coli strain JA184 (lane 4), and with10 μg of crude extract of JA184 in the presence of 125 μM cAMP (lane 5).