SPACI score report for 1xnb in ASTRAL 1.73:

WARNING! The SPACI score for this entry is not valid. This is not an X-ray structure, so the resolution and R-factor listed may be arbitrary and not valid.

PDB Entry: 1xnb
SPACI score: 0.64 (not valid)
AEROSPACI score: 0.64 (not valid)

Experiment type: -
Resolution: 1.49
R-factor: 0.165
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -1.562
WCK2 WHAT_CHECK Ramachandran: -0.938
WCK3 WHAT_CHECK Chi angles: -0.804
WCK4 WHAT_CHECK Backbone: -5.535

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).