A novel system for the preparation of orphan receptor ligand peptides

A new system is established for the preparation of biologically active recombinant peptides. The system consists of two newly developed chemical methods in combination with recombinant DNA technology. One method is a cleavage reaction by cyanylation from a recombinant fusion protein. The other is a scission reaction of an N-terminal extra-methionine by transamination from a recombinant peptide. This system is successfully established for the synthesis of three orphan receptor ligand peptides; apelin, prolactin-releasing peptide, and galanin-like peptide, isolated in our Research Division. The results show that this system is very versatile and might be useful in the preparation of biologically active peptides.