Figure 3From: Functional identification of HugZ, a heme oxygenase from Helicobacter pyloriAbsorption spectroscopy of hemin binding to recombinant HugZ. (A) Absoption profile of hemin at various concentrations. Hemin (2.5 mM in 20 mM NaOH) was titrated in 2.5 μM increments (0, 2.5, 5, 7.5, 10, 12.5, 15, 17.5, 20, 22.5, 25, 27.5, 30 μM) against 20 μM 6 × His-HugZ. Absorbance changes are indicated by the position and direction of the arrows. (B) Hemin: 6 × His-HugZ binding stoichiometry and affinity. Values were plotted as change in absorbance at 411 nm against hemin concentration. The data are representative of triplicate independent spectrophotometric analyses.Back to article page