Preparation of biologically active recombinant human progastrin1-80

Abstract

The bacterial expression of human progastrin6-80 has been reported previously [Baldwin, G.S. et al. (2001) J. Biol. Chem. 276: 7791-7796]. The aims of the present study were to prepare full-length recombinant human progastrin1-80 and to compare its biological activity with that of progastrin6-80 in vitro, to determine whether or not the N-terminal five amino acids contributed to activity. A fusion protein of glutathione-S-transferase and human progastrin1-80 was expressed in Escherichia coli, collected on glutathione-agarose beads, and cleaved with enterokinase. Progastrin1-80 was purified by reversed-phase and anion exchange HPLC and characterized by radioimmunoassay, amino acid sequencing,..