SPACI score report for 1t6i in ASTRAL 2.08:

PDB Entry: 1t6i
SPACI score: 0.25
AEROSPACI score: 0.25 (mutant; see below)

Experiment type: XRAY
Resolution: 2.81
R-factor: 0.235
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 0.472
WCK2 WHAT_CHECK Ramachandran: -1.436
WCK3 WHAT_CHECK Chi angles: -2.141
WCK4 WHAT_CHECK Backbone: 5.688

The AEROSPACI score for this entry is lower than the SPACI score because human-curated comments on the entry in SCOPe contain the phrase mutant. The full comment is: "mutant"

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).