Figure 4

FtsB/FtsL/FtsQ complex models. Representative structures of FtsB/FtsL/FtsQ complex models produced during dynamics simulation. A. Trimeric 1:1:1 model. FtsB are shown in blue, FtsL in green and FtsQ in red. The interacting residues described in the text are in stick form, coloured by atom type and grouped by the pair of proteins involved in the interaction. Leucines in the zipper between FtsB and FtsL are shown in grey sticks. N indicates the N-terminal residue of each protein. The C-terminals are omitted for clarity, but all three are placed at the top of the figure. B. Hexameric 2:2:2 model. The colour coding is the same as explained in A. C. Solvent accessible surface of the trimeric model, showing the regions identified previously in the proteins as crucial for the interaction. In purple, the FtsQ POTRA domain (residues 58 to 126); in burgundy, the FtsQ C-terminal domain (residues 127 to 145); in red, the FtsQ residues reported to be essential for FtsB/FtsL recruitment (245 to 260); in pale green, the FtsL coiled-coil region (residues 61 to 95); in green, the FtsL residues reported to be crucial for interaction with FtsQ (96 to 109); in marine blue, the FtsB coiled-coil region (region 25 to 67); in light blue, the FtsB region not identified to participate in any interaction (residues 68 to 84); in blue, the FtsB region identified to interact with FtsQ (residues 84 to 88); in grey, the leucine residues involved in the leucine-zipper between FtsB and FtsL. D. Solvent accessible surface of the hexameric model, with the same colour coding as above. In C and D, the left panels correspond to the same view as A and B, and the right panels correspond to a 180° rotated view.