Figure 4

FSSP (on the left) and 3D-Fun (on the right) Z-score of the most similar protein with the same enzyme function at the 1^st, 2^nd and 3^rd EC level versus Z-score of the most similar protein with different enzyme function at the 1^st or 2^nd or 3^rd EC level. Calculation was conducted for 3,135 sequentially non-redundant structures of known function. Corresponding histograms are shown below the charts. If FSSP Z-score = 17 and 3D-Fun Z-score = 8 were used as a cutoff value we would obtain sensitivity of 70% and 78% with specificity at 64% and 66%, respectively.