Figure 3

Growth of H. influenzae strains with human hemoglobin as the sole heme source. Growth of the H. influenzae strain Rd KW20, the dppC insertion mutant strain TMV1262 and the complemented dppC mutant strain HI2208 in hdBHI supplemented with human hemoglobin as the sole heme source. Wildtype strain Rd KW20 with human hemoglobin at 30 μg ml^-1 (solid circles) and at 10 μg ml^-1 (solid triangles). The dppC insertion mutant strain TMV1262 with human hemoglobin at 30 μg ml^-1 (open circles) and at 10 μg ml^-1 (open triangles). The complemented dppC mutant strain HI2208 with human hemoglobin at 10 μg ml^-1 (solid squares). Results are mean ± SD for quintuplicate results from representative experiments. The Kruskal-Wallis test was used to compare growth of Rd KW20 and TMV1262 over the entire 24 hour growth period at either concentration of hemoglobin P < 0.0001 and to compare growth of TMV1262 and HI2208 over the entire 24 hour growth period in 10 μg ml^-1 hemoglobin (P < 0.0001 for all comparisons).