Treponema Pallidum

Treponema Pallidum is a spirochete bacteria that has two subspecies that cause human disease. These are T. pallidum subspecies pallidum, which causes venereal syphilis; and T. pallidum subspecies pertenue, which causes yaws.

Spirochaetales

References

Sheila A. Lukehart. Chapter 153. "Syphilis" in Dennis L. Kasper, Eugene Braunwald, Anthony S. Fauci, Stephen L. Hauser, Dan L. Longo, J. Larry Jameson, and Kurt J. Isselbacher, Eds.Harrison's Principles of Internal Medicine, 16th Edition