FIG 5.

Heme promotes susceptibility of E. faecalis to host defenses. (A and B) Growth profiles (as determined by OD₆₀₀ readings) of E. faecalis JH2-2 (A) and OG1X (B) grown in the absence or presence of 10 μM heme. (C and D) Catalase activity (expressed as mM H₂O₂ degraded in 1 h by 10⁷ CFU) of E. faecalis JH2-2 (C) and OG1X (D) grown in the absence or presence of 10 μM heme. (E and F) Survival of E. faecalis JH2-2 (E) and OG1X (F) after 6 h in blood pretreated with DPI or an identical volume of DMSO solvent alone. In each case, data are the mean of results of four experiments in duplicate. For panels E and F, three different blood donors were used. Error bars represent the standard deviations of the mean. Data were analyzed by a one-way ANOVA with Tukey's post hoc test, which revealed significant differences (P < 0.01) in panels C and D between bacteria grown in the absence or presence of heme. In panels E and F, an asterisk indicates a P of <0.01 and NS (nonsignificant) indicates a P of >0.05 when the indicated comparisons were made.