FIG. 5.

Growth of P. gingivalis in batch culture in basal medium with hemin (1 μg/ml). Heme-depleted cells of P. gingivalis were preincubated for 1 h at 37°C in IhtB peptide-specific antiserum which had been heat inactivated at 56°C for 30 min (⧫), heat-inactivated NRS (▴), or basal medium with hemin (■). Points represent the mean of three independent determinations. OD, optical density.