Identification and characterization of molecular species of collagen in ordinary muscle and skin of the Japanese flounder Paralichthys olivaceus

Pepsin-solubilized collagens prepared from ordinary muscle and skin tissues of the Japanese flounder (Paralichthys olivaceus) were separated into two fractions, major and minor, by ammonium sulfate precipitation. Collagens in these fractions were further purified by cation-exchange column chromatography. The results of SDS–PAGE, peptide mapping and amino acid analysis of collagen in both fractions suggested that the purified major and minor collagens might be classified as types I and V collagens, respectively. Each type of collagen was fundamentally similar, among the ordinary muscle and the skin, in amino acid composition and peptide maps.