FIG 4.

P. aeruginosa ΔflgG and ΔfleN ΔflgG fail to assemble FOMCs. (A) A representative slice from a ΔflgG tomogram shows the MS/C-rings (arrow). (B) A representative slice from a ΔfleN ΔflgG tomogram shows two MS/C-rings (arrows). (C) A surface view of the tomogram in (B) shows seven MS/C-rings. (D) A central section from the averaged structure of the MS/C-rings. The distal rod is absent, while both MS/C-rings and expert apparatus are clearly resolved. (E) A surface view of the averaged structure shows the MS-ring (colored in cyan) embedded in inner membrane (IM) and the C-ring in blue. (F) Number of motors (or MS/C-rings) and FOMC observed in different strains. White bars represent motors (MS-ring and C-ring) found in cells; black bars indicate FOMCs. No FOMCs were seen in ΔflgG and ΔfleN ΔflgG cells.