Table 3

Statistics for refinement of molecular model. Of the residues in the structure, 70.3% lie in the most favorable regions of the Ramachandran plot as defined in the program PROCHECK (41), and no nonglycine residues are in disallowed regions.R factor = 100 × Σ∥F obs| − |F calc∥/Σ|F obs|, where F obs are the observed structure factors and F calc are the calculated structure factors. The crystallographic R factor R crystis based on 95% of the data used in refinement, and the freeR factor R free is based on 5% of the data withheld for the cross-validation test.

ParameterValue
Resolution range (Å)8.0–1.9
Sigma cutoff (F)
Number of working set reflections (|F| > 3σ)19,244
Number ofR free set reflections937
Rcryst(%)21.0
Rfree (%)26.5
Number of atoms (protein/water)2,066/509
Root-mean-square deviations from ideal geometry
Bond lengths (Å)0.005
Bond angles (degrees)1.4
Dihedral angles (degrees)25.0
Improper angles (degrees)0.64