SPACI score report for 1ykk in ASTRAL 2.07:

PDB Entry: 1ykk
SPACI score: 0.38
AEROSPACI score: 0.38

Experiment type: XRAY
Resolution: 2.06
R-factor: 0.21
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 3
WCK1 WHAT_CHECK Packing: -2.057
WCK2 WHAT_CHECK Ramachandran: -1.086
WCK3 WHAT_CHECK Chi angles: -0.847
WCK4 WHAT_CHECK Backbone: 2.119

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).