Proteolytic enzyme that degrades native collagen. After initial cleavage, less specific proteases will complete the degradation. Collagenases from mammalian cells are metalloenzymes and are collagen‐type specific (collagenase 1, collagenase 2, and collagenase 3). They may be released in latent form (proenzyme) into tissues and require activation by other proteases before they will degrade fibrillar matrix. They are involved in the degradation of collagen during tissue repair or during embryonic and fetal development. Called also interstitial collagenase.