SPACI score report for 1k90 in ASTRAL 2.07:

PDB Entry: 1k90
SPACI score: 0.25
AEROSPACI score: 0.25

Experiment type: XRAY
Resolution: 2.75
R-factor: 0.215
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 3
WCK1 WHAT_CHECK Packing: -1.922
WCK2 WHAT_CHECK Ramachandran: -4.485
WCK3 WHAT_CHECK Chi angles: -2.379
WCK4 WHAT_CHECK Backbone: 2.153

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).