Figure 2

Visualization of the flagellar sheath. (A and B) Negative-staining EM images of the sheathed polar flagellum of B. melitensis stained with uranyl acetate 2%. (B)The central filament is indicated by black arrowheads with F and the sheath by white arrowheads with S. Bar, 200 nm. (C and D) Capture of the basal region of the flagellum. The image shows the basal body region (B with black arrow), the hook (H with black arrow) and is finished by the filament (F with black arrow). The structure is surrounded by a sheath extended from the outer membrane (S, white arrowheads). Bar, 100 nm. The images B and D are enlarged from the dotted square in image A and C respectively.