FIG. 2.
Scanning electron micrographs showing examples of morphological variants of the central body and protrusions of strain SSD-17BT. (A) Central body with two protrusions (relaxed state). (B) Central body with two coiled protrusions (contracted stage). (C) Detail of coiled protrusions showing helical winding; occasionally thin filaments are visible (arrows). (D) Protrusions exhibiting lateral polyp-like protuberances. (E) Central body exhibiting protrusions with chains of microspheres. (F) Terminal bacterial body with a helical protrusion (one coil) and several extended polyp-like secondary protuberances, frequently with terminal bulbous structures of various diameters.