Table 2.

Data collection and refinement statistics

	β-NRX1+4	β-NRX2+4	β–NRX3Δ4
Data Collection
Space group	C2	C2221	P212121
a, b, c (Å)	85.8, 59.8, 105.7	51.7, 102.1, 78.5	74.7, 83.4, 119.8
α, β, γ(°)	90, 103.9, 90	90, 90, 90	90, 90, 90
Resolution (Å)	2.7 (2.8-2.7)	2.35(2.43-2.35)	2.00 (2.07-2.00)
Rsym	0.090(0.325)	0.088 (0.258)	0.120(0.628)
I/σI	19.7 (2.2)	28.8 (3.6)	14.6(2.3)
Completeness (%)	98.9 (93.4)	99.6 (92.9)	99.6(99.5)
Redundancy	3.6(3.0)	5.8(3.4)	5.9(5.4)
Refinement
Resolution (Å)	20-2.7	20-2.35	20-2.0
Rwork/Rfree	0.206/0.287	0.19/0.252	0.177/0.215
B-factors (Å2)
All atoms	35.8	34.9	30.6
Protein	35.7	34.6	28.7
Ca2+	N/A	42.4	61.8
Water	37.0	37.7	37.0
R.m.s deviations
Bond lengths (Å)	0.008	0.013	0.009
Bond angles (°)	1.234	1.555	1.196

One crystal was used per dataset. Values in parentheses are for the highest resolution shell.

$$\begin{array}{l}{R}_{\mathit{sym}}=\sum _{\mathit{hkl}}\sum _i|I_i(\mathit{hkl})-\langle I(\mathit{hkl})\rangle |/\sum _{\mathit{hkl}}\sum _i{I}_i\\ R_{\mathit{work}}=\sum _{\mathit{hkl}}\left|\right|F_{\mathit{obs}}(\mathit{hkl})|-|F_{\mathit{calc}}(\mathit{hkl})\left|\right|/\sum _{\mathit{hkl}}|F_{\mathit{obs}}(\mathit{hkl})|\end{array}$$

R_free = R_work calculated using 5% of the reflection data chosen randomly and omitted from the start of refinement.