Flagellar rotation and the mechanism of bacterial motility

BACTERIAL flagella are generally composed of three morphologically distinguishable regions: (a) the long flagellar filament which accounts for more than 95% of the flagellar protein; (b) the hook, which is generally 80–90 nm long and has a characteristic shape, and (c) the basal structure which is composed of an intricate set of disks and rods attaching the hook to the cell membrane and cell wall1–3.