Figure 2. Different positions of the Rieske Iron-sulfur cluster relative to heme irons. Iron-Iron distances are taken from references 1, 2, and 3. The distance between the Rieske cluster and the low potential heme of cytochrome b is plotted on the vertical axis, and that to the heme of cytochrome c₁ on the horizontal axis. Blue dots represent positions approximating the cytochrome b position, red dots approximate the cytochrome c₁ position, and the green dot represents the intermediate position found in one monomer of the P6₅ crystal. The data labels identify the following structures: I4₁22- entry 1QCR (bovine tetragonal [1]). Chicken + stigmatellin- entry 3BCC. P6₅- entry 1BGY, chain E [3]. P2₁2₁2₁- entry 1BCC (chicken); P6₅22R- rabbit hexagonal[2]; P2₁- beef monoclinic[2]; P6₅22B- bovine hexagonal[2]; P6₅22I- entry 1BE3 (flash-frozen, dehydrated beef hexagonal[3]).