The structure of flagellum of a gram positive bacterium and a gram negative bacterium differs because of different

Bacterial flagellum consists of three basic parts: the filament, hook and the basal body. The third part – basal body, is very important as it consists of several rings that anchor the flagellum into the plasma membrane and the cell membrane. A gram negative bacterium contains two pairs of rings that are attached to the different layers of the cell wall and the outer pair is specifically attached to the outer layer of the cell wall. As the outer cell wall is absent in a typical gram positive bacterial cell wall, it contains only the inner pair of rings that are inserted into the cell wall and plasma membrane. This structural arrangement of flagellum differentiates gram positive and gram negative bacterial cell’s flagella.