title: Evidence for mammalian collagenases as zinc ion metalloenzymes.
abstract: Collagenases (EC 3.4.24.3) from human skin, rat skin and rat uterus were inhibited by the chelating agents EDTA, 1,10-phenanthroline and tetraethylene pentamine in the presence of excess Ca2+, suggesting that a second metal ion participates in the activity of the enzyme. Collagenase inhibition by 1,10-phenanthroline could be both prevented and reversed by a number of transition metal ions, specifically Zn2+, Co2+, Fe2+ and Cu2+. However, Zn2+ is effective in five-fold lower molar concentrations (1-10(-4) M) than the other ions. Furthermore, Zn2+ was the only ion tested able to prevent and reverse the inhibition of collagenase by EDTA in the presence of excess Ca2+. Atomic absorption analysis of purified collagenase for Zn2+ showed that Zn2+ was present in the enzyme preparations, and that the metal co-purifies with collagenase during column chromatography.
mesh_terms: D000818:Animals; D002614:Chelating Agents / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D005260:Female; D006801:Humans; D008667:Metalloproteins / Q000378:metabolism; D003012:Microbial Collagenase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010618:Phenanthrolines / Q000494:pharmacology; D051381:Rats; D012867:Skin / Q000201:enzymology*; D014599:Uterus / Q000201:enzymology*; D015032:Zinc / Q000378:metabolism*
chemical_list: D002614:Chelating Agents; D008667:Metalloproteins; D010618:Phenanthrolines; D004492:Edetic Acid; D003012:Microbial Collagenase; D015032:Zinc