general morphology and description of Spirochaetes
✔ extremely narrow
✔ elongated
✔ cylindrical in shape
✔ spiral with tight coils and tapered ends
✔ actively motile; exhibit rotational movement
✔ possess internal flagella [also referred to as endoflagella, periplasmic flagella, axial fibrils, axial filaments]
✔ gram-negative
Genera of Spirochaetes associated with human infection
(1) Treponema
(2) Borrelia
(3) Leptospira