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Medical Term:


Pronunciation: spi'ro-ke'ta


A genus of motile bacteria (order Spirochaetales) containing presumably gram-negative, flexible, undulating, spiral-shaped rods that may or may not possess flagelliform, tapering ends. The protoplast is spirally wound around an axial filament. No obvious periplast membrane or cross-striations occur. These organisms are motile by means of a creeping motion over the surfaces of supporting objects. They are not parasitic but are found free living in fresh or sea water slime; they are commonly found in sewage and foul water. At present the genus contains five species. The type species is Spirochaeta plicatilis.

[Mod. L. fr. G. speira, a coil, + chaite, hair]

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