_EC 3.1.16.- Exonucleases active with either ribo- or deoxyribonucleic acids a 8 PDB entries  
EC 3.-.-.- Hydrolases. [51,972 PDB entries]
EC 3.1.-.- Acting on ester bonds. [12,883 PDB entries]
EC 3.1.16.- Exonucleases active with either ribo- or deoxyribonucleic acids a [8 PDB entries]
EC 3.1.16.1 spleen exonuclease. [8 PDB entries]