Fig. 6.
Spin–spin distance measurements in the outer cleft, with color codes referring to biochemical and structural states as defined in Fig. 3. (A) CW EPR spectra (low field portion). A noninteracting control (labeled single-Cys mutant) is shown in gray. (B) Background-corrected DEER decays, normalized to constant modulation depth and offset vertically for clarity. (C) Distance distributions from DEER fits, assuming a sum of two Gaussians. Arrows indicate Cβ–Cβ distances in crystal structures.