Interstitial collagenase from rat mammary carcinoma cells: interaction with substrates and inhibitors.

Functional characteristics of the interstitial collagenase purified from the BCl rat mammary carcinoma cell line were examined and compared with literature reports of the corresponding characteristics of collagenase from non-neoplastic cells. BCl collagenase degraded soluble collagen types I, II and III at the same rate and degraded fibrillar tendon collagen with an activation energy of 75 kcal/mol; these characteristics were identical to collagenase from normal rat uterine smooth muscle cells. Degradation of fibrillar collagen by BCl collagenase was completely inhibited by rat alpha 2-macroglobulin which was concomitantly cleaved into half-fragments. BCl collagenase was also inhibited by native and recombinant tissue inhibitor of metalloproteinases, a synthetic peptide collagenase inhibitor (Z-pro-leugly-NHOH), and Zn2+. In all functional characteristics examined, BCl collagenase was the same as interstitial collagenases from non-neoplastic sources.