Figure 2
Hemoglobin stimulates a robust growth of Spn D39 in standard (iron-complete) medium. THYB was inoculated with D39 cells grown on BAPs (18 h, starting O.D.600 = 0.05. Shown is growth in (A) THYB with 0–20 µM hemoglobin (Hb); (B) THYB with 20 µM BSA, denatured hemoglobin, filtered hemoglobin, or the flow-through; (C) THYB with or without catalase. (D) THYB supplemented with 0–80 µM FeNO3 (Fe); (E) THYB with 0–40 µM heme (Hm). The data are representative of three independent experiments performed in triplicates; error bars indicate SD. (F) Total intracellular iron content measured by ICP-MS in culture samples (normalized to optical density) grown in THYB, THYB with 20 µM hemoglobin (Hb), or THYB with 80 µM FeNO3 (Fe). The data represents the average of three independent biological replicates; error bars indicate SD. The asterisks denote statistical significance, P ≤ 0.05 (THYB vs. Fe, and Hb vs. Fe, Student's t-test).
