title: A neutral proteinase from human gingival fibroblasts active against the c-terminal cross-linking region of type I collagen.
abstract: An enzyme that was capable of releasing small fragments containing hydroxynorleucine from the c-terminal extra-helical region of the alpha 1 chain of reduced (tritiated) soluble type I collagen was found, along with collagenase, in medium that had been conditioned by the culture of human gingival fibroblasts (Gin-1). The enzyme was present in a latent form or forms and could be activated by treatment with either trypsin or p-hydroxymercuribenzoate. It was maximally active at neutral pH and inhibited by EDTA. It is suggested that this enzyme, acting within a region of the molecule which is of major importance in stabilizing fibrillar collagen through intermolecular cross-linking, could potentially play an important role in collagen turnover in vivo.
mesh_terms: D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism*; D005881:Gingiva / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D046911:Macromolecular Substances; D003012:Microbial Collagenase / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D046911:Macromolecular Substances; D003094:Collagen; D010447:Peptide Hydrolases; D003012:Microbial Collagenase