Table 1.

Structural statistics for refinement of the EI(H189Q) mutant structure based on RDCs and SAXS/WAXS

	RDCs with no noise	RDCs with random noisea
RDC R-factor (%)b	19.0±0.4	19.6±0.7
RDC DaNH (Hz)	11.1±0.2	11.1±2.4
RDC η	0.59±0.02	0.58±0.06
SAXS/WAXSc
q = 0.022 → 0.44 Å−1	0.58±0.09	0.58±0.13
q = 0.022 → 1.0 Å−1	0.76±0.16	0.78±0.19
Coordinate precision
EIN domaind
Cα rms displacement (Å)	2.2	2.7
rotation (deg.)	5.8	7.3
EINα subdomaine
Cα rms displacement (Å)	2.1	2.5
rotation (deg.)	3.8	5.3

^a2% random noise added to experimental RDCs with a different distribution of random noise for each structure calculated. The values of the RDC R-factor, D_a^NH and η are reported with respect to the experimental RDCs (with no noise added). The RDC R-factor is calculated as ^Rinf = [<(D_obs-D_calc)²>/(2<D_obs²>]^1/2 where D_obs and D_calc are the observed and calculated RDCs, respectively.¹⁸

^bThe RDC data comprise 40×2 backbone N-H RDCs for the dimer, 20 for each subdomain of each EIN subunit.

^cStructures are refined against SAXS/WAXS data for q ≤0.44 Å⁻¹ and the χ² values reported for all the data (up to q = 1.0 Å⁻¹) are obtained with the parameters from the fits to the data up to q = 0.44 Å⁻¹; these χ² values therefore report on how well the structures obtained using data up to q = 0.44 Å⁻¹ predict the data from q = 0.44 to 1.0 Å⁻¹.

^dThe EIC domain is superimposed and fixed, and the position of the EIN domain compared.

^eThe EIN^α/β subdomain is superimposed and fixed, and the position of the EIN^α subdomain is compared.