Purification and characterization of bovine dental sac collagenase

1. Active type collagenase was purified as much as 140-fold from the explant medium of bovine dental sacs and showed a single band on disc gel electrophoresis. Purified collagenase cleaved native collagen at only one locus under physiological conditions, but hydrolyzed neither gelatin nor alpha-casein. The optimal pH was about 7.8. 2. The molecular weight of active type enzyme was 35,000 by gel filtration and 34,000 by gel electrophoresis. The activation of latent type of collagenase resulted in the reduction of molecular weight from 45,000 to 38,000 by gel filtration. 3. A small but detectable amount of collagenase was directly extracted from frozen and thawed bovine dental sacs. In explant media of frozen and thawed tissue and fresh tissue with actinomycin D, some activity was detected for the first 2 days, but essentially no collagenase activity was detected in the explant medium after day 3. 4. The latent type collagenase was activated by trypsin, 4-aminophenylmercuric acetate (4-APMA), thiocyanate and deoxycholate (DOC). DOC showed irreversible dissociation of latent type enzyme in similar fashion to that exerted by 4-APMA. 5. The purified collagenase was inhibited by bovine serum, EDTA, o-phenanthroline, cysteine and dithiothreitol.