Cleaves collagen type I. May play a role in larval tissue degeneration and adult organogenesis during amphibian metamorphosis. May be involved in tail resorption. Binds 1 zinc ion per subunit. Up-regulated in the tail by thyroid hormone. Expressed only transiently in whole animal, at time when tadpole feeding begins. Expressed at high level as the tadpole tail resorbs and during hindlimb morphogenesis and intestinal remodeling. The conserved cysteine present in the cysteine-switch motif binds the catalytic zinc ion, thus inhibiting the enzyme. The dissociation of the cysteine from the zinc ion upon the activation-peptide release activates the enzyme. Belongs to the peptidase M10A family.