FIG 5 .

The CagY middle repeat region (MRR), but not the T4SS pilus, is required to bind α₅β₁ integrin in a host cell-free system and is expressed on the bacterial surface. (A and B) Immunoblot detection of the CagY MRR and VirB10 region in bacterial lysates. (C and D) Immunofluorescent detection of the CagY MRR on the surface of nonpermeabilized H. pylori. (E and F) Flow channel competitive adherence to α₅β₁ integrin. Results are expressed as the ratio of deletion mutant to WT adherence and represent the mean ± SEM from at least 3 independent experiments. ***, P < 0.001.