SPACI score report for 3ptb in ASTRAL 2.06:

PDB Entry: 3ptb
SPACI score: 0.56
AEROSPACI score: 0.56

Experiment type: XRAY
Resolution: 1.7
R-factor: 0.182
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 3.255
WCK2 WHAT_CHECK Ramachandran: -1.063
WCK3 WHAT_CHECK Chi angles: -0.205
WCK4 WHAT_CHECK Backbone: 2.086

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).