3.4.11.6 aminopeptidase B periodontal ligament enzyme probably derived from blood 35992 3.4.24.24 gelatinase A periodontal ligament - 712141, 712166 3.4.24.35 gelatinase B periodontal ligament periapical ligament 700539 3.4.24.7 interstitial collagenase periodontal ligament - 708406 3.4.24.B4 matrix metalloproteinase-13 periodontal ligament - 677406, 711595