Figure 2: Crystallographic analysis of FimH conformational states.

(a) FimH^F18·DsG in the A_free (left) and in the A_bound states (FimH^F18·DsG·HM) in comparison with the S_bound state of FimH^K12·DsF·HM and the isolated FimH_L^F18·HM (right). The FimH_L, FimH_P, DsF and DsG are coloured in red, yellow, green and blue. The experimentally in crystallo trapped orientation of FimH_P in FimH^K12·DsF·HM and a modelled position based on a hinge motion stretching around Gly157 is indicated. A schematic representation for each crystal structure, similar to Fig. 1a, is given. The tip of the clamp loop and the C terminus of FimH_L are indicated as a circle and diamond, respectively. (b) Comparison of the conformation of the ligand-binding site in the A_bound (red) and S_bound (orange) states with the isolated lectin domain FimH_L (grey) and (c) comparison of the interdomain interface of the lectin domain.