Figure 3.

EPR spectra recorded on nonirradiated (a) and γ-irradiated (b–d) oriented multilayers of purified cytochrome bc₁ complex from Rv. sulfidophilum. Spectra were taken before warming (b), after warming to 100 K (c) (for 5 min), to 200 K (for 5 min, not shown), and to room temperature (d) (for 15 min). Continuous and dashed lines denote spectra taken with the magnetic field parallel and perpendicular to the plane membrane, respectively. Instrument settings are as in Fig. 1.