Terminal electron transport in Treponema pallidum.

Reduced-minus-oxidized difference spectra of sonically treated virulent Treponema pallidum disclosed cytochromes of the b anc c types as well as large amounts of flavoprotein. Difference spectra of the carbon monoxide-binding pigment identified cytochrome o as the terminal oxidase. Physiological reduction of the cytochromes indicated that the cytochrome system was functional and established the capability of T. pallidum for aerobic respiration. The potential significance of these findings is discussed.