SPACI score report for 3tat in ASTRAL 2.08:

PDB Entry: 3tat
SPACI score: 0.09
AEROSPACI score: 0.09

Experiment type: XRAY
Resolution: 3.5
R-factor: 0.213
PCK1 PROCHECK Ramachandran: 2
PCK2 PROCHECK Chi-1 angle: 4
PCK3 PROCHECK H-bonds: 3
WCK1 WHAT_CHECK Packing: -3.721
WCK2 WHAT_CHECK Ramachandran: -6.741
WCK3 WHAT_CHECK Chi angles: -7.448
WCK4 WHAT_CHECK Backbone: 0.053

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).