FIG. 9.

Corynebacterium diphtheriae pili. A. Genetic organization of the spa locus of C. diphtheriae NCTC13129. Predicted promoters as well as the direction of transcription are shown with arrows. B to D. Corynebacterial pili stained with specific antiserum (anti-SpaA [B], anti-SpaB [C], or anti-SpaC [D]) and IgG-conjugated 12-nm gold particles. Samples were viewed by transmission electron microscopy. Bars indicate a distance of 0.2 μm. (Adapted from reference 204 with permission of Blackwell Publishing.)