SPACI score report for 1k53 in ASTRAL 2.05:

PDB Entry: 1k53
SPACI score: 0.43
AEROSPACI score: 0.43

Experiment type: XRAY
Resolution: 2.1
R-factor: 0.213
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 1
WCK1 WHAT_CHECK Packing: -0.71
WCK2 WHAT_CHECK Ramachandran: -1.454
WCK3 WHAT_CHECK Chi angles: 1.616
WCK4 WHAT_CHECK Backbone: 3.323

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).