Fig. 4.

Binding potential and inhibition of HpHtrA by compounds 2, 3, and 4, and the activity of HpHtrA mutants. (A) SPR response for binding of compounds 2, 3, and 4 to immobilized HpHtrA. (B) Recombinant E-cadherin was incubated with HpHtrA and several concentrations of compounds 1 (reference inhibitor) and 3. Reduction of full-length E-cadherin (E-Cad), cleavage products (CP1, CP2) and enzyme loading (HtrA) are shown. (C) HpHtrA wt cleaves E-cadherin. HpHtrA S₂₂₁A, S₁₆₆A, N₂₀₈A, K₃₂₈A and S₁₆₄A show no or very limited proteolytic activity against E-cadherin. (D) HpHtrA wt, HpHtrA S₁₆₆A, N₂₀₈A, K₃₂₈A and S₁₆₄A are proteolytically active against casein, only the active-site mutation S₂₂₁A loses all activity.