Matrix metalloproteinases (MMP’s) belong to a family of secreted or membrane-associated zinc endopeptidases capable of digesting extracellular matrix components. The recombinant human MMP-13, expressed as the pro-enzyme, becomes highly active when incubated with APMA. It can be used in FRET-based enzyme activity assays or as a positive control for zymography, Western blot, IP, and ELISA.