Table 2.

X-ray diffraction data collection and refinement statistics.

	Human USP2-Ub-6TG complex	Human USP2 C276S mutant-Ub complex
Data Collection
Space group	C2	C2
Cell dimensions
a, b, c (Å)	103.0, 54.7, 72.7	102.5, 54.0, 74.8
β (°)	107.5	107.8
Resolutiona (Å)	30–1.80 (1.86–1.80)	30–1.24 (1.28–1.24)
Rmergeb (%)	5.1 (46.6)	3.4 (24.1)
I/σI	19.9 (2.4)	33.0 (5.7)
Completeness (%)	97.9 (80.1)	98.5 (96.9)
Redundancy	3.7 (3.5)	3.6 (3.4)
Refinement
Number of reflections	33,397 (4,726)	102,800 (14,652)
R factorc (%)	17.9 (26.7)	14.8 (15.9)
Free R factord (%)	23.8 (31.0)	16.4 (18.2)
Number of atoms	3,568	3,761
Protein	3,285	3,404
Ligand/ion	11/11	0/1
Water	261	356
B-factors (Å2)
Protein	38.9	14.7
Ligand/ion	65.2 (40.7)e/57.9	−/13.7
Water	50.9	23.9
rmsd
Bond length (Å)	0.012	0.007
Bond angles (°)	1.5	1.2
Ramachandran analysis (%)
Favored	91.6	92.6
Allowed	8.4	7.5

^aThe numbers in parentheses are for the highest-resolution shell.

^b$R_{merge}=\sum _h\sum _i|I_{hi}-\langle I_h\rangle |/\sum _h\sum _i{I}_{hi}$, where I_hi is the integrated intensity of a given reflection and $\langle I_h\rangle$ is the mean intensity of multiple corresponding symmetry-related reflections.

^c$R=\sum _h|F_h^o-F_h^c|/\sum _h{F}_h^o$, where $F_h^o$ and $F_h^c$ are the observed and calculated structure factors, respectively.

^dFree R is R calculated using a random 5% of data excluded from the refinement.

^eThe value in parentheses is calculated at 50% occupancy.