Residues conserved in space in a test case and the corresponding R-HET. The R-HET corresponding to the THIOL_PROTEASE_HIS pattern (table on the left) and the 3D superimposition of the corresponding residues. The side chains of the residues belonging to the THIOL_PROTEASE_HIS PROSITE pattern are represented in yellow. Other colours are used to represent the side chains of the residues not belonging to the PROSITE signature, whose 3D position is conserved across the different structures. In the case of the G160 and G164 residues, corresponding to A370, the Cα is represented (as a sphere) instead of the side chain. Residues identified by the computational procedure are in green. Residues added to the R-HET by visual inspection are in magenta. For the figure, residues belonging to the R-HET only, were structurally re-aligned.