SPACI score report for 2a2s in ASTRAL 1.75:

PDB Entry: 2a2s
SPACI score: 0.67
AEROSPACI score: 0.67

Experiment type: XRAY
Resolution: 1.7
R-factor: 0.178
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -1.251
WCK2 WHAT_CHECK Ramachandran: -0.692
WCK3 WHAT_CHECK Chi angles: 0.546
WCK4 WHAT_CHECK Backbone: -1.016

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).