Vertebrate Collagenase

In both the ay and a2 chains of type I collagen, degradation of the protein begins with cleavage of the Gly-De or the Gly-Leu bond by collagenase. 

The enzyme vertebrate collagenase was partially purified from a lyophilized tissue culture medium of back skin from tadpoles. The medium was harvested, 

2 Dlpeptldyl Carboxypeptldase (Angiotensin I Converting Enzyme, EC 3.4.15) (Baranowskl et al., 1982 Dolg and Smiley, 1993) 

---

Whereas the use of synthetic substrates in lieu of native collagen is appropriate in studies with collagenase from clostridial sources, their use in studies of collagenases derived from vertebrate sources cannot be endorsed at this time. The actual amino acid sequence and or other structural requirements that may be recognized by vertebrate collagenases are still unknown. Until these requisites have been determined, we will not know whether splitting of a synthetic substrate represents nonsi)Ccific peptidase activity or specific collagenolytic effect. 

Vertebrate tissues knowm to produce specific collagenases include tadpole skin (epithelium only), human gingivae (epithelium and connective tissues), human skin (epithelium and dermis), bone, synovium, and polymorphonuclear leukocytes from the peripheral blood. With the exception of the W hite blood cells, culture is presently required for detection of all other vertebrate collagenases. Uniformly negative results for specific collagenases have been achieved in preparations of vertebrate tissues (except for leukocytes) designed to permit detection of enzymes in lyso-somes. Present data are consistent with the view that collagenase is not stored in celis rather it is produced and released into the extracellular environment w here it may act or be inactivated. 

---