Structure of human collagenase 3 complexed to a sulphone-based hydroxamic acid. According to its overall fold, this metalloprotease is included into the metzincin clan. The name of this clan refers to a conserved motif called "methionine turn" present after the consense HEXGHXXGXXH catalytic site.
The catalytic site of this protease contains a Zn atom (shown as a golden sphere) complexed by His222, His226, and His232. It also contains Glu223, which is supposed to provide a general base to attack the target peptidic bond by interacting with a water molecule. See family M03 for an example of this interaction.



  • Structures are rendered as ribbons. Catalytic and catalytic metal-complexing residues are shown as neons. Inhibitors are displayed as space filling spheres.

  • Carbons are shown in light gray, hydrogens in cyan, oxygens in red, nitrogens in blue, and sulfurs in yellow.

  • Left-click and drag to rotate the protease. Right-click and drag up/down to zoom in/out. Click with both buttons and drag to move the protease. Use the upper bar to get different views and for display options. For a close-up of the catalytic site, choose the cat_site view.

  • Once you have clicked inside the structure window, you can use the keyboard to hide/show objects:

    '1' toggles the ribbon.
    '2' toggles the inhibitor.
    '3' toggles the catalytic residues.

  • You can download the pdf file here

  • To display and manipulate the structure, you need at least Adobe Acrobat Reader v7.0. For best results, install the last version of Acrobat Reader.

  • To hide/show elements in the structure, first you have to click inside the render window.