FIG 5.

Detection of heme in G. intestinalis. (A) The concentration of heme was determined in Giardia cytosol using HPLC. The highest heme concentration was found in cells that expressed recombinant gCYTb5-IV (b5-IV) when the cells were cultured in TYI-S-33 medium supplemented with 4 μM hemin (+ hemin). The heme content was significantly lower in the strain harboring the gCYTb5-IVH₁₇₈L mutant. (B) Western blot analysis indicated comparable levels of recombinant gCYTb5-IV in the lysates of cells cultured in the presence and absence of hemin. An anti-tubulin antibody (TAT-1; Sigma-Aldrich) was used as a loading control. The error bars indicate standard deviations.