FIGURE 6.

DDM binding to Na⁺-NQR. A, separation of 1 mg Na⁺-NQR on a 1-ml HiTrap ANX-FF column (GE-Healthcare) monitored from the absorbance at 280 nm. B, concentrations of protein (gray bars) and protein-bound DDM (black bars). The concentration of protein-bound DDM was obtained by subtracting the DDM concentration of the buffer (0.639 ± 0.015 mg ml⁻¹) from the DDM concentration of the eluate.