FIGURE 8.

Model showing orientation of extended N terminus and ligand-binding sites. A composite model was generated by positioning brartemicin, from the crystal structure of brartemicin with the CRD, in the binding site of the extended CRD with bound trehalose. The model highlights portions of the extended CRD that interact with the macrophage membrane and with glycolipid targets at the surface of mycobacteria. The N terminus is linked to the macrophage membrane by a 19-amino acid sequence not seen in the crystal structure. The binding site for mycobacterial ligands is indicated based on the orientation of brartemicin in the binding site and highlighting of hydrophobic residues implicated in ligand binding in green. Other atoms are colored as in Fig. 2.