Example of a Refined Heavy Elements Table (R-HET). The Refined Heavy Elements Table (R-HET) corresponding to the AA_TRNA_LIGASE_II_2 pattern. The residues manually added to each cell of the multiple alignment grid after visual inspection are reported in square brackets. The residues belonging to the sequence PROSITE pattern are underlined. Residues are indicated in one-letter code and the number corresponds to the residue number in the PDB file.