SPACI score report for 1ud1 in ASTRAL 1.75:

PDB Entry: 1ud1
SPACI score: 0.23
AEROSPACI score: 0.23 (mutant; see below)

Experiment type: XRAY
Resolution: 3.1
R-factor: 0.193
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 3
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -1.034
WCK2 WHAT_CHECK Ramachandran: -3.129
WCK3 WHAT_CHECK Chi angles: -4.46
WCK4 WHAT_CHECK Backbone: 0.319

The AEROSPACI score for this entry is lower than the SPACI score because human-curated comments on the entry in SCOP 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).