SPACI score report for 2kug in ASTRAL 2.07:

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. The resolution is not available. An arbitrary resolution has been used. The R-factor is not available and an abitrary R-factor has been used. The PROCHECK parameters for this entry could not be obtained, and poor results have been arbitrarily assumed.

PDB Entry: 2kug
SPACI score: 0.05 (not valid)
AEROSPACI score: 0.05 (not valid)

Experiment type: NMR
Resolution: 4
R-factor: 0.25
PCK1 PROCHECK Ramachandran: N/A
PCK2 PROCHECK Chi-1 angle: N/A
PCK3 PROCHECK H-bonds: N/A
WCK1 WHAT_CHECK Packing: -1.309
WCK2 WHAT_CHECK Ramachandran: -1.447
WCK3 WHAT_CHECK Chi angles: -3.548
WCK4 WHAT_CHECK Backbone: 4.533

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).