Elucidation on the True Character of the Extracellular Tubule of Leptospira Cell

Extracellular tubule (ECT) of leptospira cell was examined for elucidation of its true character. After treatment by several methods, the sphcrical bodies or destroyed cells were observed under transmission electron microscopy. ECT frequently appeared and showed close connection with an axial flagellum (AF). An AF was a supercomplex of two complexes, one was the sheath and the other was the core. The former was made up from three parts, limiting membrane, amorphous substance layer and helical string, and the latter was from amorphous substance layer and a filament containing flagellin. Each complex was usually stable itself, and the latter was put into the former. However, both were separatable under unusual conditions by physico-chemical treatment. The latter was easily escapable from the former, the remained sheath complex, frequently showed a tubular image. Therefore, it was concluded that ETC was nothing but the remained sheath complex of an axial flagellum after falling off of the core complex.