Promoter-lacZ fusions carried out in the wild-type strain and in the ptxS-deficient strain confirmed that PtxS represses gene expression in the wild-type strain. EMSAs showed that PtxS binds to its target promoters. Also, by using EMSAs it was shown that 2-ketogluconate freed PtxS from its target sequence. After the transcription start sites were identfied, footprinting analysis showed that PtxS protects a single region within each of the promoters. In each of the protected regions a perfect palindromic sequence was found.
Regulated genes for each binding site are displayed below. Gene regulation diagrams show binding sites, positively-regulated genes, negatively-regulated genes, both positively and negatively regulated genes, genes with unspecified type of regulation. For each indvidual site, experimental techniques used to determine the site are also given.
|Site sequence||Regulated genes||Gene diagram||Experimental techniques||TF function||TF type|