Figure 6.

StcE mucinase digestion fragments both WT and ldlB α-DG. A, CHO and ldlB cells were labeled with either ManNAz or GalNAz followed by cell lysis in the presence of a protease inhibitor mixture. Lysates were then treated with or without V. cholerae neuraminidase, and Western blotting was performed using an anti–α-DG core antibody. Relative intensity of the α-DG band was quantifying from three separate experiments. Error bars represent standard error; **, p < 0.01. B and C, CHO (B) and ldlB (C) cells were treated with various concentrations of purified StcE mucinase (1 h), and lysates were resolved by SDS-PAGE prior to Western blotting using the anti–α-DG core antibody. A representative image of two independent experiments is shown. Note the relative stability of the fragments following mucinase cleavage in both cell lines. D, representative Western blotting comparing VC neuraminidase and StcE (2 h) treatment in ldlB cells using the anti–α-DG core antibody. IB, immunoblot.