Figure 4

Mapping of cyt b₅ residues minimally affected by the increasing ionic strength when in complex with BHT-bound CYP2B4.

(A) Increase in relative intensities (ΔI) of cyt b₅ resonances at 100 mM (blue), 250 mM (magenta) and 400 mM (yellow) NaCl, each calculated relative to 0 mM NaCl. Residues with ΔI more than one standard deviation below the average are highlighted in red in the histogram in (A) and are mapped in magenta onto the cyt b₅ structure for 100 mM NaCl (B), 250 mM NaCl (C) and 400 mM NaCl (D). The following residues are found to be highlighted in all the three figures (B, C and D): D65, V66, T70, D71 and A72. These residues are most likely involved in specific interactions during complex formation.