Fig. 5

DegP and DegQ, but not DegS cleave E-cadherin in vitro. a DegP, DegQ and DegS wildtype (wt) of EPEC (Ep) and the corresponding inactive mutants (SA) were tested in in vitro cleavage assays using E-cadherin (rEcad) as a substrate (upper panel). EpDegP^wt and EpDegP^SA were detected using anti-EpDegP antibody (lower panel). b The E-cadherin-cleavage activity of EPEC (Ep) DegP, DegQ and DegS was compared with the activity of P. mirabilis (Pm) DegQ and DegS. EpDegP and PmDegQ were detected using polyclonal antibodies. c The selective activity of EpDegS was shown in in vitro cleavage experiments using 7 μg EpDegS and 9 μg recombinant RseA (rRseA) as a substrate. To stimulate the activity of EpDegS, 100 μM YFF activator peptide or equal amounts of diluent (−) were added as indicated. 300 ng rEcad was included in the reactions where indicated. Aliquots of samples were analyzed by Western blotting to detect E-cadherin (upper panel) and the remaining sample was separated by SDS PAGE following coomassie staining to detect the degradation of RseA (middle panel) and EpDegS proteins (lower panel). The asterisk (*) indicates GST protein co-purified with the EpDegS protein