PURIFICATION DIRECTED CLONING OF PEPTIDES

摘要

The present invention is directed to microbial and higher organism methods for expression and ligand immobilized affinity purification of a product peptide. The biological compositions of the invention which are produced by these methods include or are designed to express, a protein purification construct having three tandem, coupled segments composed of a binding protein, an interconnecting peptide and a variable fused polypeptide which incorporates the product peptide in one or more copies. According to the method of the invention, the following steps will allow production of the product peptide: (a) host cell or host organism expression regulated by the recombinant expression vector carrying the recombinant gene coding for the protein purification construct; (b) purification of the protein purification construct by a ligand immobilized affinity separation technique; and (c) enzymatic or chemical cleavage of the protein purification construct to produce the product peptide.