The stoichiometric activation of human skin fibroblast pro-collagenase by factors present in human skin and rat uterus

Purified human skin fibroblast collagenase zymogen was used as a substrate for activators partially purified from the medium of cultured human skin and rat uterus. Analysis of the activated enzyme by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that these activators do not produce measurable changes in the molecular weight of the zymogen. Kinetic analysis indicated a noncatalytic mechanism of action for these activators, since zymogen activation was independent of incubation time, and dependent only upon the concentration of the activator fractions. These results are consistent with a Stoichiometric mechanism of procollagenase activation by these macromolecules.