Identification and partial characterisation of the non-collagenous amino- and carboxyl-terminal extension peptides of cartilage procollagen.

Procollagen secreted by embryonic chick cartilage cells has been partially purified by (NH₄)₂SO₄ precipitation and DEAE-cellulose chromatography. Analyses of the products of digestion by human rheumatoid synovial collagenase and bacterial collagenase indicated the presence of non-collagenous peptide sequences at the N- and C-termini. Both regions were found to incorporate [³⁵S]cystine but inter-chain disulphide bonds were restricted to a C-terminal location. Electrophoretic analysis gave apparent molecular weights of 13000 and 36000 daltons for the respective N- and C-terminal extensions.