Interaction of lipids with acid-soluble bovine skin collagen

Acid-soluble bovine skin collagen was found to contain lipids even after exhaustive extractions with chloroform-methanol. To determine if this lipid fraction was bound covalently to collagen, the protein was partially hydrolyzed by chemical or enzymatic agents to yield a series of polypeptide fragments. Each of these polypeptides was isolated and found to be free of any accompanying lipid. It is concluded that the associated lipids of soluble bovine skin collagen are bound by weak intermolecular forces.