Skip to main content
Figure 3 | BMC Microbiology

Figure 3

From: Integration Host Factor (IHF) binds to the promoter region of the phtD operon involved in phaseolotoxin synthesis in P. syringaepv. phaseolicola NPS3121

Figure 3

Bioinformatic analysis of the sequence upstream of the phtD operon, and Supershift and Shift-western experiments to analyze the DNABII-family proteins binding activity to the P phtD fragment. (A) Bioinformatic analyses. This panel schematizes the intergenic region between phtC and phtD where the IHF binding site position is represented with a yellow barrel. The alignment of the phtD IHF binding site with the consensus IHF binding site proposed by Kur et al [27] is also shown. The sequence identified as the putative IHF binding site in the phtD promoter is shown in bold red letters. W: A or T; R: A or G; N, any base. (B) Supershift assays. Analyses were conducted using increasing concentrations of anti DNAB-II family proteins antibody. Supershift signals were observed when antibody was added to the reaction mixture. The specific DNA-protein complex is indicated by a solid arrow. Supershift bands are indicated by solid arrowheads. (C) Shift-western experiment. Gel shift assays with the P phtD probe were performed as described in the Methods, followed by transfer of proteins onto nitrocellulose membranes, which were probed with antibody to DNA-binding proteins of DNAB-II family. To identify the signal, the images were analyzed using Quantity-one software (BIO-RAD) following the manufacturer's instructions. Panel I depicts a standard gel mobility assay with radiolabeled P phtD probe. Lane 1, free probe; lane 2, DNA-protein complex. Panel II: Immunoblot using polyclonal antibody. Lanes correspond to those of Panel I. The arrow indicates the position of the gel shift band.

Back to article page