protein, nucleic acid: cartoon; ligands: spacefill; active site: sticks
(mono, stereo) (automatic, in case of more than 1 NMR structures only model 1 is shown)
The following images were kindly provided by the protease and protease inhibitor
web server PROLYSIS.
The structure of papain (PDB code: 9pap), the archetype of cysteine proteases
of the papain family, isolated from the latex of the plant Carica papaya (mono).
A comparison of papain (PDB code: 9pap) and human cathepsin B (PDB code:
1huc). The occluding loop of human cathepsin B reduces the access of protease
inhibitors to the active site. For instance, the affinity constant (Ki)
of chicken cystatin for human cathepsin B is reduced by a factor 340 as
compared to papain (mono).
A structural superimposition of papain (PDB code: 9pap) and human cathepsin
B (PDB code: 1huc) (mono).
