Isolation and characterization of the immunoglobin of pike (Esox lucius L.).

The purification of the immunoglobulin from pike serum and its physicochemical characterization is presented. The immunoglobulin was prepared by means of gel filtration and ion exchange chromatography. Measurements in the analytical ultracentrifuge showed a sedimentation constant of 15.0 S. A molecular weight of 650.000 was calculated. The immunoglobulin was composed of heavy and light chains of molecular weights 60.000 and 22.500, respectively. It is likely that the immunoglobulin of pike is composed of 8 heavy and 8 light chains and possesses a tetrameric structure. The heavy chains contain 9.2% sugars and amino sugars. The amino acid composition of the chains is similar to that of other fish immunoglobulins.