FIELD: genetic and biological engineering. SUBSTANCE: object of invention is attained by means of recombination plasmide pLT 16 DNA containing semi-synthetic LT gene and constituting source of C-terminal fragment of gene employed for constructing pLT 9 plasmide. Recombination pLT 16 plasmide includes pDSpu1 plasmide DNA Hind III - Sau 3AT-fragment incorporating M 13 bacteriophage envelope protein gene promotor, β-lactamase gene, chloramphenicolacetyl transpherase gene and l phage transcription terminator (3,49), pFPZ plasmide Hind III - Ecor I-fragment including semi-synthetic human lymphotoxin gene and recombination pLT 9 plasmide that codes polypeptide of mature human lymphotoxin, in which ten N-terminal amino acid residues are substituted by Vae residue, and consists of r6f23 plasmide DNA Hind III - Kpn-fragment including tandem of T7 bacteriophage early region A2 and A3 promotors, b-lactamase gene and l phage transcription terminator (3,4), and Kpn I - Hind III-fragment including synthetic portion of translation indication and semi-synthetic gene of transformed human lymphotoxin. E. coli SG 20050/pLT 9 allows polypeptide biosynthesis level of up to 4×105 unit/ml cell cultures. EFFECT: higher level of biological synthesis of human lymphotoxin. 4 cl
