Active site plasticity revealed from the structure of the enterobacterial N-ribohydrolase RihA bound to a competitive inhibitor

Table 1 Crystallographic data

*Data collection*
Resolution range (Å)	37.5-2.1	2.21-2.1
Number of observed reflections	232,754	31,773
Number of unique reflections	68,457	9,929
Completeness (%)	97.2	95.4
Multiplicity	3.4	3.2
Mean I/σ(I)	8.1	3.0
R_sym	0.122	0.388
Refinement
Resolution range (Å)	37.50-2.1	2.15-2.1
Number of reflections (F > 0)	65,238	4,760
R_crys	0.203	0.254
R_free	0.241	0.304
rmsd bonds (Å)	0.020
rmsd angles (°)	1.689
Mean B factor (Å²)	30.3
Model quality
Residues in favored regions of Ramachandran plot (%)	97.8
Residues outliers in Ramachandran plot (%)	0.5
Unusual rotamers (%)	0.9

Data collection and refinement statistics for the RihA-DAPIR complex.
R_sym = ∑_hkl∑_i||I_i(hkl)|-|<I(hkl)||>|/∑_hkl∑_i|I_i(hkl)|, where I_i(hkl) is the ith measurement of reflection hkl, and <I(hkl)> is the average value from the individual measurements
R_crys = ∑_hkl||F_o(hkl)|-|F_c(hkl)||/∑_hkl|F_o(hkl)|, where F_o(hkl) and F_c(hkl) are the measured and calculated structure factor of reflection hkl, respectively
R_free, same as R_crys, but calculated on a subset of randomly-selected reflection excluded from all stages refinement (3,455 total, 265 in the highest resolution shell).

ISSN: 1472-6807