Table 1.

Q-factors for fits of CaM PRE data

	intradomain fita			full molecule fitb
	intra	inter	all	intra	inter	all
CaM-4Ca2+-MLCKc
S17C	0.16	0.41	0.22	0.17	0.21	0.18
A128C	0.13	0.34	0.17	0.13	0.25	0.15
CaM-4Ca2+ d
S17C	0.17	0.99	0.29	0.17	0.99	0.29
A128C	0.13	0.99	0.49	0.14	0.99	0.49
Apo CaMe
S17C	0.16	0.96	0.17	0.16	0.96	0.17
A128C	0.35	0.93	0.36	0.35	0.93	0.36
Apo CaM + MLCKe
S17C	0.20	0.96	0.30	0.20	0.96	0.30
A128C	0.42	0.93	0.55	0.44	0.92	0.54

^aParamagnetic tag positions were fit to intradomain PREs only (residues 1-76 for the N-terminal domain; residues 83-148 for the C-terminal domain), and the Q-factors were then calculated for intradomain, interdomain, or all PREs.

^bParamagnetic tag positions were fit to PREs for the full molecule, and Q-factors were then calculated for intradomain, interdomain, or all PREs.

^cQ-factors calculated for experimental PREs from CaM-4Ca²⁺-MLCK, fit to crystal structure of CaM-4Ca²⁺-MLCK complex (PDB 1CDL)⁴ (Fig. 1C).

^dQ-factors calculated for experimental PREs from CaM-4Ca²⁺, fit to “dumbbell” crystal structure of CaM-4Ca²⁺ (PDB 1CLL)³ (Fig. 1B).

^eQ-factors calculated for experimental PREs from Ca²⁺-free CaM (with or without peptide, as indicated), fit to NMR structure of apo CaM (PDB 1CFD)² (Fig. 1A). Note that while the structure for the entire molecule of apo CaM was deposited in the PDB and is used in the calculations presented in this table, there were, in fact, no interdomain NOE restraints (or any other NMR restraints) to orient the two domains relative to one another.²