1.Collagen forms the major fraction of connective tissues such as skin, bone, tendon, the vascular system of animals and the connective tissue sheaths surrounding muscle. Its contents vary, depending on fish species.
2. Most fish collagens have been found to consist two α - chain variants, which are normally designated as α-1 and α-2 .
3. Collagen basic structure made up of three polypeptide chains, three polypeptide chains coiled together to form a right-handed triple helix. And each polypeptide chain is characterized by the repeating structure of Glycine,proline,hydroxyproline.