Characterization of the Promoter, MxiE Box and 5′ UTR of Genes Controlled by the Activity of the Type III Secretion Apparatus in Shigella flexneri
Figure 3
Promoter activity of MxiE box-containing regions.
β-galactosidase activity was assayed in derivatives of the wild-type (open bars) and ipaB (filled bars) strains harboring a plasmid carrying a ∼67-bp fragment, encompassing nucleotides −57 to +11 with respect to the proposed transcription start site of each gene (Fig. 2), inserted 5′ of lacZ in the promoter probe vector pQF50. Gene names are indicated below the bars. Activities are expressed in Miller units.