A rapid sensitive collagenase assay.

A rapid, sensitive collagenase assay has been developed using¹⁴C-acetylated collagen as a substrate. Acid-soluble calfskin collagen was labeled with 1-¹⁴C]acetic anhydride at pH 8. The acetylated collagen had a specific activity of 6.25 × 10⁵ dpm/mg protein. Collagen was not denatured as evidenced by its resistance to nonspecific proteolysis and sensitivity to bacterial collagenase. Polyacrylamide gel electrophoresis of the acetylated protein showed that the radioactivity was present in the three bands corresponding to the α, β, and γ components of collagen. The rate of release of ¹⁴C from labeled collagen by Clostridium histolyticum collagenase was proportional to enzyme and substrate concentration.