ANTIGENICITY AND CHEMICAL COMPOSITION OF AN ENZYMATIC DIGEST OF ELASTIN

Bovine ligamentum nuchae elastin, after solubilization by pancreatic elastase, was dialyzed and fractionated on a column of DEAE-Sephadex A-50. The resulting fractions were analyzed for their component amino acids. The first fraction eluted had the greatest average peptide chain length and 87% of its residues as the three nonpolar amino acids-glycine, valine, and proline in the ratio 2:2:1, with insignificant amounts of the polar amino acids and cross-linking agents. It was found not to have any antigenic sites. Another fraction which was the major component of the digest contained the cross-links in an amount three times that found in complete elastin but was only weakly antigenic. The fraction with the greatest antigenicity was found to be enriched in polar amino acids and tyrosine; it also contained 7% carbohydrate as glucose and 50% lipid. © 1969.