An inhibitor of collagenase from human amniotic fluid. Purification, characterization and action on metalloproteinases.

1. An inhibitor of collagenase of apparent mol.wt. 28000 was isolated from term human amniotic fluid. 2. It is active against mammalian collagenases from a number of species and tissues as well as other mammalian metalloproteinases, but has no activity against bacterial metalloproteinases. 3. Activity is destroyed by treatment with either trypsin or 4-aminophenylmercuric acetate, by heat, and by reduction and carboxymethylation. 4. All the properties observed suggest that it is similar to the synthesized tissue inhibitor of metalloproteinases.