SPACI score report for 1kxw in ASTRAL 1.63:

PDB Entry: 1kxw
SPACI score: 0.49
AEROSPACI score: 0.49 (mutant; see below)

Experiment type: XRAY
Resolution: 1.96
R-factor: 0.168
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 1.081
WCK2 WHAT_CHECK Ramachandran: -0.097
WCK3 WHAT_CHECK Chi angles: -0.001
WCK4 WHAT_CHECK Backbone: -0.07

The AEROSPACI score for this entry is lower than the SPACI score because human-curated comments on the entry in SCOP contain the phrase mutant. The full comment is: "mutant"

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).