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Prokaryotic flagella

Prokaryotic flagella are only 20nm thick. As a result, they are only visible with special stains which increase the diameter of the flagella. There can be flagella at one (polar) or both ends (nonpolar) of the cell. Lophotrichous flagella are tufts of flagella. The flagellin is helically shaped protein forming a flattened helix. The distance between adjacent curves is wavelength. This flagellin helix rotates. The bottom of the flagellin helix, which connects to the cell, widens to form hook. Filament connected to motor by single protein. Motor anchored in cytoplasmic membrane and cell wall. Small central rod passing through series of rings (proton motive force). Rotary motor consists of rotor and stator. Rotor has C, MS and P rings (basal body). Stator is Mot proteins (generate torque). In gram(-), outer L ring anchored in lipopolysaccharide. 2nd ring, p ring, anchored in peptidoglycan of cell wall. Third set, MS in cytoplasmic membrane and C ring in cytoplasm. In gram(+), lacking a outer membrane, only inner pair of rings present. Surrounding ring are Mot proteins. Fli porteins reverse rotations.

Rotary nano-motor consisted of rotor and stator. Rotor has C, MS and P rings. These are the basal body. Stator is Mot proteins and generate torque. Rotary impoarted from basal body. Proton motive force is energy source. Grows from tip.

Prokaryotic flagellaComments