view article
Figure 3
Crystal structure of the ligand-free Y137A FimH mutant. Electron density is displayed in white or light rose contourings at 1.5σ (2Fo − DFc) for residues of the molecule in the asymmetric unit (green) and for the neighbouring FimH (yellow), respectively. (a) Proximity of the mannose-binding Asp54 at the bottom of the pocket (shown as a green ball-and-stick model) to the EDTA-binding cavity. Ile52 is shown as a magenta ball-and-stick model. Ile52 couples the two sites displayed in more detail in (b) and (c). (b) The EDTA-binding cavity of ligand-free Y137A FimH, with hydrogen bonds from EDTA to Asn136, Thr53 and Glu50 shown as blue ball-and-stick models. (c) The mannose-binding pocket showing the strong hydrogen bond of Asp54 to the FimH lectin-domain C-­terminal carboxylate of Thr158 in the symmetry-related FimH molecule 1.

IUCrJ
Volume 4| Part 1| January 2017| Pages 7-23
ISSN: 2052-2525
https://doi.org/10.1107/S2052252516016675