INVESTIGATION OF BIOSYNTHESIS OF HUMAN LYMPHOTOXIN IN CELLS OF RECOMBINANT ESCHERICHIA-COLI STRAIN

The effect of cultivation conditions on the biosynthesis of human lymp hotoxin in recombinant Escherichia coil SG20050/pLT21 strain was studi ed. Cells of the producing strain were grown in Luria broth containing chloramphenicol. The highest biomass yield of the recombinant strain and plasmid DNA stability were observed under these conditions. To enh ance the level of lymphotoxin production an inoculate containing fresh ly obtained or frozen with glycerol transformants of the producing str ain were used, and the cultivation process was performed at 32 degrees C. As a result, lymphotoxin was synthesized in a soluble form without the formation of inclusion bodies. A study of the protein synthesis d ynamics during the cultivation of E. coli at 32 degrees C showed that the highest lymphotoxin activity was observed during the exponential g rowth phase, being maximal at the end of the exponential phase and at the beginning of the stationary phase. The set of indicated methods al lowed us to maximize and stabilize the production of lymphotoxin in a biologically active form with a final yield of 18-20% from cell protei n.