Fig. 2
Expression of two htrA gene copies in H. pylori enhances the overall proteolytic activity of HtrA. a H. pylori wild-type strain 26695 (Hp wt) and 26695 transformed with htrA 26695 were grown for 24 h in BHI broth medium in the presence or absence of 1 or 2 mM IPTG, respectively. Bacterial pellets were prepared and subjected to investigation of protease activity by casein zymography. The position of proteolytically active HtrA monomers (MMs) and oligomers (OMs) is indicated with arrows. M, protein size marker. b The band intensities of proteolytically active HtrA proteins were quantified densitometrically. The relative HtrA activity is given in “fold change”