SPACI score report for 1zkl in ASTRAL 2.07:

PDB Entry: 1zkl
SPACI score: 0.58
AEROSPACI score: 0.58

Experiment type: XRAY
Resolution: 1.67
R-factor: 0.194
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 1
WCK1 WHAT_CHECK Packing: 0.15
WCK2 WHAT_CHECK Ramachandran: 1.308
WCK3 WHAT_CHECK Chi angles: 0.552
WCK4 WHAT_CHECK Backbone: 1.473

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).