quality:correction, quality:corruption, structural:expansion
Bacteriology

Treponema pallidum subspecies pallidum is a spiral-shaped, Gram-negative, highly mobile bacterium. Two other human diseases are caused by related Treponema pallidum subspecies, yaws (subspecies pertenue) and bejel (subspecies endemicum), and one further caused by the very closely related Treponema carateum, pinta. Unlike subspecies pallidum, they do not cause neurological disease. Humans are the only known natural reservoir for subspecies pallidum. It is unable to survive more than a few days without a host. This is due to its small genome (1.14 Mbp) failing to encode the metabolic pathways necessary to make most of its macronutrients. It has a slow doubling time of greater than 30 hours. The bacterium is known for its ability to evade the immune system and its invasiveness.