| 摘要 |
PURPOSE:To obtain a antitumor and physiologically active polypeptide, consisting of a specific amino acid sequence and having excellent specific activity and stability and useful for treating cancer, etc. CONSTITUTION:A synthetic oligonucleotide obtained by synthesizing with a codon derived from a human tumor necrotic factor (TNF) protein is cloned in a vector, such as pBR322, to provide a human TNF gene expression type plasmid (e.g. pTNF401NN) (A), which is then subjected to treatment with a restriction enzyme, genetic reparative treatment, etc., to afford an antitumor active polypeptide gene expression type plasmid (e.g. pTNF416) (B). The components (A) and (B) are then introduced into Escherichia.coli to afford a recombinant microbial cell (C). The resultant cell (C) is subsequently cultivated in a culture medium containing glucose, casamino acid, etc., and the cultivated C cells are collected and subjected to treatment, such as crushing, to provide a cell lysate (D), which is then subjected to separation treatment, such as electrophoresis, to recover the aimed physiologically active polypeptide consisting of an amino acid sequence, such as an amino acid expressed by the formula. |
