Molecular characterization of fibrillar collagen from the body wall of starfish Asterias amurensis

1. The body wall collagen of starfish Asterias amurensis was disaggregated into fibrils in a neutral salt solution containing β-mercaptoethanol and then solubilized by limited pepsin digestion. 2. The pepsin-solubilized collagen was shown to consist of (α1)2α2 heterotrimers, each α chain having a molecular weight of about 100,000. 3. These collagen α chains had close similarities in the compositional feature of amino acids to Type I collagen α chains of lower vertebrates such as hagfish and shark. 4. Other species of starfish, Asterina pectinifera and Acanthaster planci, contained the same type of fibrillar collagen as a main supporting material in the body walls.