FIG 7.

Transmission electron micrographs of ultrathin sections of high-pressure-frozen, freeze-substituted, Lowicryl-embedded (A to C) or rehydrated and cryosectioned (D) K. stuttgartiensis cells incubated with affinity-purified antibodies against HZS. Thin sections were incubated with 1:200-diluted anti-HZS (A to C) or 1:300-diluted anti-HZS (D). Gold particles were visible only inside the anammoxosome. Electron-dense, iron-containing particles (16 to 25 nm; white arrowhead) were distinguished from gold labels (10 nm; black arrowhead) by size and appearance. Scale bars, 200 nm.