Figure 6.

Schematic representation of the Rieske cluster's magnetic axes with respect to the membrane in the chemically (Upper) and the irradiation-reduced (Lower) state as compared with the two different (proximal and distal) conformational states observed in the crystal structures (Protein Databank entries 3bcc and 1bcc). Only heme b_L, heme c₁, the inhibitor stigmatellin occupying the Q_o-site, and the two conformational states of the [2Fe-2S]-cluster of the ISP (together with the two ligating histidine residues) are shown.