Plasticity of the β-Trefoil Protein Fold in the Recognition and Control of Invertebrate Predators and Parasites by a Fungal Defence System
Figure 5
NMR solution structure of the CCL2 lectin in complex with fucosylated chitobiose (GlcNAcβ1,4[Fucα1,3]GlcNAc).
(A) Intermolecular NOEs observed in a 3D 13C F1-edited F3-filtered HSQC-NOESY spectrum in a schematic presentation. (B) Structural ensemble of 20 structures of the protein backbone and the carbohydrate in cyan. The subunits α, β and γ are colored green, yellow and orange, respectively. The orientation is identical to Figure 4. (C) Ribbon presentation of the most representative structure. (D) Stereo view of the carbohydrate recognition site. Potential intermolecular hydrogen bonds are shown with dashed magenta lines. (E) Details of the interaction site illustrating how the trisaccharide is recognized by hydrogen bonds. (F) Summary of the interactions between the trisaccharide and CCL2. Potential H-bonds are indicated as dotted lines in magenta and hydrophobic interactions by green lines. (G) Crystal structure of the β-trefoil domain of the fungal lectin MOA in complex with the trisaccharide Galα1,3[Fucα1,2]Gal [19] showing all three occupied canonical binding sites (pdb∶3EF2). For better comparison, the same orientation and colors as in panel B and C were used.