Fig. 4. Structural characterization of interactions between mannoside 4 and the deoxygenated compounds 5–7 and FimHLD. (A) X-ray crystal structures of mannoside 4 (black, PDB 4BUQ), 2-deoxy-mannoside 5 (blue, PDB 5L4T), 3-deoxy-mannoside 6 (green, PDB 5L4V), and 4-deoxy-mannoside 7 (red, PDB 5L4X). Hydrogen bond interactions of 4 are indicated as grey dashes. (B) 1H,15N-HSQC NMR experiments reveal chemical shift perturbations for residues in the mannose binding site in the presence of ligands. Color coding according to panel A. Nomenclature of Asn and Gln δ and ε protons according to PDB guidelines. Full spectrum is shown in Fig. S20 (ESI†).
