Fig. 5.

The MBX compound binding site overlaps with substrate binding sites. Superimposition of MBX-3132 (cyan, carbon; red, oxygen; blue, nitrogen; yellow, sulfur) bound to AcrB with substrate compounds. A) MIN (green; PDB entry 4DX5 [43]), B) R6G (magenta; PDB entry 5ENS [30]) and C) doxorubicin (orange; PDB entry 4DX7 [43]). MBX-3132 bound to the hydrophobic trap sterically hinders substrate binding to the AcrB deep binding pocket. AcrB side-chains involved in the binding of substrates or EPI are indicated and shown as sticks (carbon = yellow). Reprinted with permission from Sjuts et al. [30].