Table 6.

Crystallographic statistics

RNase A complex	2′,5′-ADP	3′,5′-ADP	5′-ADP	U-2′-p	U-3′-p
Resolution (Å)	30–1.2	30–1.5	30–1.2	30–1.5	30–1.5
(Outermost shell) (Å)	1.22–1.20	1.55–1.50	1.22–1.20	1.55–1.50	1.55–1.50
Reflections measured	949,552	423,949	623,242	278,544	239,794
Unique reflections	67,242	36,948	70,118	37,206	37,930
Rsymma	0.038	0.062	0.053	0.052	0.061
(Outermost shell)	0.226	0.369	0.130	0.390	0.294
Completeness (outermost shell) (%)	92.9	97.9	96.5	98.3	99.4
	71.2	95.5	96.9	95.6	99.6
<I/σI> (outermost shell)	30.9 (10.8)	15.1 (3.6)	20.9 (5.8)	14.1 (2.5)	15.4 (2.6)
Rcrystb	0.194	0.229	0.190	0.211	0.220
(Outermost shell)	0.261	0.446	0.195	0.442	0.412
Rfreec	0.228	0.271	0.219	0.24	0.240
(Outermost shell)	0.277	0.452	0.202	0.446	0.436
Number of solvent molecules	558	389	540	399	415
R.m.s. deviation from ideality
in bond lengths (Å)	0.011	0.004	0.011	0.004	0.004
in angles (°)	1.7	1.2	1.8	1.3	1.3
Average B factor
Protein atoms (Å2) (molecule I/molecule II)	18.6/16.7	18.8/23.6	18.2/17.7	19.0/18.7	19.0/20.2
Solvent molecules (Å2)	30.9	33.0	33.1	30.7	30.8
Ligand atoms (Å2) (molecule I/molecule II)	17.8/31.1	22.4/34.4	13.6/21.3	18.0/30.6	19.9/26.8

^aR_symm = ∑_h∑_i│I(h) − I_i(h)/∑_h∑_iI_i(h) where I_i(h) and I(h) are the ith and the mean measurements of the intensity of reflection h.

^bR_cryst = ∑_h│F_o − F_c│/∑_hF_o, where F_o and F_c are the observed and calculated structure factors amplitudes of reflection h, respectively.

^cR_free is equal to R_cryst for a randomly selected 5% subset of reflections not used in the refinement (Brünger 1992).