An alternative approach to the synthesis of a recombinant galanin-like peptide (GALP)

GALP is a novel galanin-like peptide that has been isolated from porcine hypothalamus in our Research Division. In the present study, a large quantity of porcine GALP (pGALP) was synthesized with a high degree of purity using recombinant DNA technology. A basic fibroblast growth factor (bFGF) mutein, CS23, was used as a fusion partner and pGALP was released by chemical cleavage with cyanogen bromide (BrCN). Using various criteria such as HPLC, SDS–PAGE, amino acid analysis, amino acid sequence, relative-molecular-mass measurement by liquid secondary-ion mass spectrometry, as well as biological activity, the purified molecule was shown to be pGALP and was found to have the same biological activity as a chemically synthesized standard. The pGALP obtained here will be useful for elucidation of its physiological role in vivo. Furthermore, CS23ML76, a newly prepared bFGF mutein, was found to be more appropriate than CS23 as a fusion partner in this procedure.