(Left) Quenching of the pyrene monomer emission (RFI) from pyrCL induced by the binding of cyto to egg PC vesicles (LUVs) containing 17.5 (open circles), 25 (filled circles), 33 (open triangles), 49 (filled triangles), 67 (open squares), and 100 mol% (filled squares) CL (including pyrCL). (Right) Corresponding changes of fluorescence as a function of added ATP concentration at the highest cytochrome concentration used for the data displayed on the left-hand side. Taken from ref. (Rytöman and Kinnunen 1994) with permission