| 摘要 |
PURPOSE:To obtain an excellent antitumor drug composition by culturing in medium a recombinant microorganism cell transformed with the recombinant plasmid containing a specific DNA region. CONSTITUTION:A double chain DNA region composed of a single chain DNA and another complementary single chain DNA exhibiting base sequence expressed by formula II coding a bioactive polypeptide exhibiting the amino acid sequence expressed by formula I or a polypeptide bonding with Met at amino terminal is contained in a recombinant plasmid (A) (e.g. tumor necrosis factor pTNF 493). Next, the A-component is introduced into Escherichia coli C 600r-m strain, etc., and a transformant strain (B) is obtained. Then the B- strain is cultured with ventilation and stirring in a medium containing glucose and Casamino acid, etc., at about 37 deg.C for 2-36hr to obtain a cultured substance (C). Thus, the C-component is centrifuged and resultant microorganismic cells are suspended in phosphoric acid buffer, etc., then subjected to a supersonic treatment, thus the resultant cell ligate is purified with electrophoretic method, etc., to produce a bioactive polypeptide exhibiting the amino acid sequence expressed by formula I. |
