(A) A tomographic section from a WT cell shows the motors that are embedded in
the cytoplasmic inner membrane (IM/CM). (B) A tomographic section from a
ΔflbB cell shows a motor that is embedded in the
cytoplasmic membrane. (C) The central section (left) and schematic diagram
(right) of the WT flagellar motor. (D) The central section (left) and schematic
diagram (right) of the ΔflbB flagellar motor. (E) The
surface rendering of the 3D averaged WT and (F) ΔflbB
motor structures are shown in side view. (G) The surface rendering of the 3D
averaged WT motor structure is shown in tilted top view (90°). Compared
to the motor structures from WT (C, E, G), the ΔflbB
motor lacks the entire collar (blue), the stator (orange-red), and FliL (pink)
structures. Noticeably, the collar is a large and complex structure comparing to
FliL and the stator. OM, outer membrane; PG, peptidoglycan; P, P-ring; R,
central rod; exp, export apparatus.