SPACI score report for 1s1u in ASTRAL 1.71:

PDB Entry: 1s1u
SPACI score: 0.19
AEROSPACI score: 0.19

Experiment type: XRAY
Resolution: 3
R-factor: 0.227
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 3
WCK1 WHAT_CHECK Packing: -0.92
WCK2 WHAT_CHECK Ramachandran: -3.635
WCK3 WHAT_CHECK Chi angles: -3.023
WCK4 WHAT_CHECK Backbone: -3.978

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).