Fig. 1
Chromosomal introduction of a second, inducible htrA gene copy in H. pylori. a Schematic presentation of the IPTG-inducible htrA 26695 expression construct with the chloramphenicol acetyl-transferase (CAT) cassette (top), which was cloned into the plasticity region of H. pylori between genes HP0999 and HP1000 (bottom). b This construct was transformed into H. pylori wild-type (Hp wt) strains 26695 and P12, and the expression of HtrA was investigated after 24 h growth in BHI medium in the presence or absence of 1 or 2 mM IPTG, respectively. The results for strain 26695 are shown. Western blotting using α-FlaA and α-CagA antibodies served as controls, indicating that equal amounts of proteins are present in the samples. c The band intensities of HtrA proteins were quantified densitometrically. The relative protein expression is given in “fold change”