FIGURE 5.

Electronic absorption and MCD spectra of the ferric heme-bound frog DGCR8 HBD-His₆. The electronic absorption spectrum (top panel) was taken at room temperature using the dimeric frog HBD-His₆ at 12.2 μm concentration in a buffer containing 50 mm EPPS (pH 8.0) and 400 mm NaCl. As a control, an electronic absorption spectrum was also recorded at 4 K and displayed no differences in peak positions and intensity (data not shown). The MCD spectrum (bottom panel) was recorded using a protein sample at 24.5 μm in 22.5 mm EPPS (pH 8.0), 180 mm NaCl, and 55% (v/v) glycerol.