PREPARATION OF AN ARTIFICIAL GENE ENCODING HUMAN MUTANT LYMPHOTOXIN AND ITS EXPRESSION IN ESCHERICHIA-COLI

Using the oligonucleotide directed mutagenesis, a human lymphotoxin (T NFbeta) mutant gene lacking 21 N-terminal codons has been obtained. Re combinant plasmid pLT21 for expression of the mutant gene has been con structed. The mutant gene in the plasmid was placed under control of a tandem of constitutive promoters from coliphage T7. A simple procedur e for isolation of recombinant protein was developed. The procedure al lows to obtain the highly purified biologically active mutant protein with a good yield. During biosynthesis the recombinant protein undergo es a posttranslational processing resulted in the cleavage of N-termin al methionine and leucine residues.