Table 1

Triphosphate structure of guanylate-binding protein 1 and implications for nucleotide binding and GTPase mechanism

Balaji Prakash, Louis Renault, Gerrit J.K. Praefcke, Christian Herrmann and Alfred Wittinghofer

Values in parentheses correspond to the highest resolution shell. Root mean square deviations (r.m.s.d.) are given as deviations from ideal values.
^aR_sym = _h _i\|I(h) – I_i(h)\|/_h_iI_i(h), where I_i(h) and I(h) are the ith and mean measurements of the intensity of reflection h.
^bR_work = _h\|F_o - F_c\|/_hF_o, where F_o and F_c are the observed and calculated structure factor amplitudes of reflection h.
R_free is the same as R_work, but calculated on the 5% of the data set aside from refinement.
Data collection and phase determination by molecular replacement method
Crystal space group	C2 (a = 161.23 Å, b = 42.65 Å, c = 91.54 Å, = 100.2°)
Parameter	Native
Resolution (Å)	41.2–1.7
High resolution shell (Å)	1.8–1.7
X-ray source	ID2, ESRF
Wavelength (Å)	0.9903
Completeness (%)	99.2 (74)
Unique reflections	67 508
Redundancy	5.2 (3.9)
R_sym^{^a} (%)	8.4 (25.1)
I/	14.9 (3.7)
Refinement statistics
resolution	41.2–1.7 Å
reflections (work set/test set)	64 141/3366
protein atoms	4587
no. of water molecules	411
average B (Å²)	23.1
R_work^{^b}	22.6%
R_free^{^b}	25.5%
r.m.s.d. bond length	0.005 Å
r.m.s.d. bond angles	1.1°