Fig. 4.

Fourth to fifth day of Rickettsia helvetica infected Vero cells. a Morphology of R. helvetica in partly decomposed host cells. Note the leaflets (arrow heads) and inner plasma membrane enclosing the periplasmatic space (ps). Fibrillate nucleic acid is clearly visible (long arrows) ×120,000. Bar  150 nm. b Anti-rickettsia antibodies with gold particles (gp) (15 nm) on Lowicryl-embedded cells. Leaflets and plasma membrane are visible (arrows heads) as well as fibrillar nucleic acid (long arrows). The immunoreaction is mainly located along the membrane/leaflet part of the rickettsia but sparsely scattered all over the organism ×120,000. Bar  150 nm