mersalyl and Carcinoma-256--Walker

A latent form of collagenase had been isolated from crude extracts of the insoluble, fibrous material from Walker tumor homogenates. Purified preparations of this enzyme yielded a major unit of Mr approximately 62000, as determined by gel filtration on AcA 54 Ultrogel. In its activated form collagenase had been purified to apparent homogeneity with an approximate Mr of 42000. The active enzyme cleaved soluble collagen into three-quarter and one-quarter length fragments in the manner of vertebrate collagenases. Latent collagenase from culture media eluted with an apparent Mr of 53000 and was thus slightly larger in size than its activated form that eluted at 42000. Extracted latent collagenase and latent collagenase from culture media could be activated enzymatically by trypsin or chymotrypsin and non-enzymatically by mersalyl, an organic mercurial compound. We suggest that latent collagenase from Walker tumors are complexes of active enzyme with inhibitor(s) of low molecular weight(s) and are not true zymogens.

Topics: Animals; Carcinoma 256, Walker; Chromatography, Gel; Chymotrypsin; Collagen; Enzyme Activation; Male; Mersalyl; Microbial Collagenase; Molecular Weight; Rats; Rats, Inbred Strains; Trypsin