GENETIC-ENGINEERING PREPARATION OF OXYTOC INOYLLYSINE

A hybrid protein, Il-Ox-K, was obtained from cells of E. coli TG1/pTOT Eilox strain. The N-terminal sequence of this protein (63 amino acid r esidues) is a fragment of human interleukin-3, and the C-terminal sequ ence represents the full amino acid sequence of oxytocin flanked by a lysine residue. The modified oxytocinoyl-Lys containing S-sulfocystein e residues was isolated after tryptic digestion of S-sulfoderivative o f the hybrid protein. The modified peptide was converted into the cycl ic form containing the disulfide bonds Cys(1)Cys(6). Obtaining the oxy tocinoyl-Lys proves the possibility of preparing short peptides using the microbiological synthesis.