Elastin hexapeptide repeating

Early reviews are available on the development of the molecular conformation of the tetrapep-tide, pentapeptide, and hexapeptide repeating sequences of elastin and on the mechanism of elasticity of the basic elastic-contractile model protein. These may be sought for historical background. Recent reviews of the mechanism of elasticity and its relation to contractility may be examined for a more... 

Tropoelastin is the soluble precursor of elastin and consists of alternating hydrophobic and hydrophilic peptide domains. The most common amino acids in the hydrophobic domains are Gly, Val, Ala, and Pro, which are often present in repeats of tetra-, penta-, and hexapeptides, such as Gly-Gly-Val-Pro, Gly-Val-Gly-Val-Pro, Gly-Val-Pro-Gly-Val, and Gly-Val-Gly-Val-Ala-Pro, respectively [3, 4]. The hydrophilic domains are mainly composed of lysines interspersed by alanines. 

Calcium in this case would coordinate with acyl oxygens from the polypeptide backbone of the protein, because of its unique amino acid sequences and potential conformations348). Non-polar peptides have been isolated from elastin which consists almost entirely of the three non-polar amino acids glycine, valine, and proline349). Portions of porcine tropoelastin have been partially sequenced350). Repeating tetra-, penta-, and hexapeptides have been observed. The tetrapeptide contains the sequence —Gly—Gly—L—Val—L—Pro— the pentapeptide —L—Val—L—Pro-... 

Structural proteins such as collagen, elastin, and spider silk contain repeating sequences of amino acids. In 1983, Waite discovered that the protein secreted by the phenol gland of the blue sea mussel Mytilus edulis consists of closely related decapeptide and hexapeptide sequences with a combined molecular weight of approximately 130 kilodaltons (kDa).i He further elucidated that this protein is transformed into glue through enzymatic oxidation to form the adhesive plaques that anchor the mussel... 

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