Experimental and predicted distances between different azurin monomers in the azurin T21R1 crystal structure. A) Selection from the crystal packing that was used as input for the spin labelling programs. Red spheres indicate the label positions. The grey monomer was included to complete the environment of the spin label on monomer I. B) Distances between the monomers in panel A). Distances from the X-ray structure are pink, distances predicted by MMM are green and distances predicted by mtsslWizard are blue. For MMM the distances were taken from the .html output file generated by the program. C) close up of the II-III distance for mtsslWizard (top) and MMM (bottom). The experimental distance was taken from the X-ray structure and is shown in pink. The distance vector predicted by mtsslWizard is shown in blue and connects the geometric averages of the two ensembles predicted by the program (blue sticks). The green vector is the distance vector between the occupancy weighted geometric average of the MMM predicted ensembles (green sticks). For MMM, the occupancy of the individual rotamers is represented by the thickness of the sticks. Thus, only rotamers with a predicted occupancy larger than zero are shown.