COMPARATIVE BIOCHEMICAL-ANALYSIS OF SEA-URCHIN PERISTOME AND RAT TAILTENDON COLLAGEN

We report here a biochemical comparison between type I rat tail tendon collagen and collagen isolated from sea urchin peristome tissue. The sea urchin collagen consisted of two species of apparent mol masses, 1 40 and 116 kDa. Amino acid compositional analysis of the 140 and 116 k Da species revealed the presence of hydroxyproline and hydroxylysine a s well as a glycine content of 28.1 mol.%. In solubility experiments t he rat tail tendon collagen was found to precipitate at sodium chlorid e concentrations between 1 and 2 M while peristome collagen remained s oluble at salt concentrations as high as 4 M Incubation of the peristo me and rat tail tendon collagen preparations with a sea urchin collage nase/gelatinase resulted in cleavage of the former but not the latter collagen. Upon heat denaturation at 60 degrees C, however, the rat tai l tendon collagen served as a substrate for the gelatinase. Cyanogen b romide cleavage of rat tail and peristome collagens generated largely unique peptide maps. Collectively, these results suggest that structur al differences exist between echinoderm and vertebrate type 1 collagen s. (C) 1997 Elsevier Science Inc.