[1] Collagen, a key component of the animal extracellular matrix, is made through cleavage of pro-collagen by collagenase once it has been secreted from the cell.
Clostridium histolyticum is a pathogen that causes gas gangrene; nevertheless, the isolated collagenase has been used to treat bed sores.
[citation needed] Analysis of the primary structure of the gene product from Clostridium perfringens has revealed that the enzyme is produced with a stretch of 86 residues that contain a putative signal sequence.
The known metal ligands are His, Glu, Asp, or Lys and at least one other residue is required for catalysis, which may play an electrophillic role.
Of the known metalloproteases, around half contain an HEXXH motif, which has been shown in crystallographic studies to form part of the metal-binding site.