Table 1. Parameters (τ_r) describing the mobility of the spin label of αS bound to natural membranes from simulations of cw-EPR spectra.

τ_r: rotation-correlation time.

condition	αS spin label positions	fast component		slow component		immobile component
		τ r (ns)	contribution (%)	τ r (ns)	contribution (%)	τ r (ns)	contribution (%)
buffer	αS56	0.45± 0.02	100	na	na	na	na
	αS69	0.31±0.02	100	na	na	na	na
IMM	αS56	0.45	2.0±0.5	2.88±0.13	90 ±1.5	>50.0	8.0
	αS69	0.31	2.0±0.5	2.23±0.11	98 ±1.0	na	na
NPM	αS56	0.45	2.0±0.5	2.95±0.14	88±1.5	>50.0	10.0
	αS69	0.31	2.2±0.3	1.99±0.13	98±0.3	na	na

na: not contributing in the simulation. For error determination, see Materials and Methods.