The procollagen-C-proteinase cleaves the C-propeptides of types I, II, and III collagen, as well as laminin 5 and lysyl oxidase precursor. Curiously, the enzyme is partially identical to Bone Morphogenetic Protein 1 (BMP-1) or the mouse tolloid protease, and related to Drosophila tolloid, Astacin, and BP10.