EXPRESSION OF HYBRID GENES CONTAINING THE SEQUENCE CODING FOR HUMAN ADRENOCORTICOTROPIN IN ESCHERICHIA-COLI

Recombinant plasmids coding for hybrid proteins that contain human adr enocorticotropic hormone (ACTH) were constructed. The ACTH-coding sequ ence was fused with the Staphylococcus aureus protein A gene via a syn thetic adaptor preserving the reading frame. The hybrid protein was pu rified by affinity chromatography. The hybrid protein production was 6 -8 mg per liter of bacterial culture, most synthesized protein was sec reted to the periplasm. In strain with decreased protease activity, th e secretory vectors obtained significantly enhanced the expression and provided export of the bulk of hybrid protein to the culture liquid. The hybrid protein was specifically hydrolysed, yielding protein A and human ACTH. The amino acid composition of samples purified by HPLC co incided with that of authentic ACTH.