Stromelysin 1 (EC 3.4.24.17, matrix metalloproteinase 3, proteoglycanase, collagenase activating protein, procollagenase activator, transin, MMP-3, neutral proteoglycanase, stromelysin, collagen-activating protein) is an enzyme. This enzyme catalyses the following chemical reaction Stromelysin 1 (EC 3.4.24.17, matrix metalloproteinase 3, proteoglycanase, collagenase activating protein, procollagenase activator, transin, MMP-3, neutral proteoglycanase, stromelysin, collagen-activating protein) is an enzyme. This enzyme catalyses the following chemical reaction This extracellular endopeptidase is present in vertebrate tissues.