SPACI score report for 1jon in ASTRAL 1.55:

PDB Entry: 1jon
SPACI score: 0.31
AEROSPACI score: 0.31 (mutant; see below)

Experiment type: XRAY
Resolution: 2.5
R-factor: 0.216
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -0.16
WCK2 WHAT_CHECK Ramachandran: -1.697
WCK3 WHAT_CHECK Chi angles: -0.426
WCK4 WHAT_CHECK Backbone: -0.477

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: "separately expressed fragment; 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).