AN OPTIMIZED EXPRESSION OF RECOMBINANT HEPCIDIN: USING PICHIA PASTORIS

Expression and purification of small peptides have always been problematic due to enzymatic degradation and many other technical problems. We report cloning and expression of a low molecular weight human antimicrobial peptide ?hepcidin' (Hepc, 20 amino acids) in pPIC9K transformed into P. pastoris GS115. The study reveals that active hepcidin peptide can be successfully expressed in this methylotrophic yeast. The BMMY medium was found to be optimal for the hepcidin protein expression and growth of the recombinant strains. Hepcidin protein expressed in recombinant strains was about 3 mg/L. Peptide expression was verified by Western blotting and ELISA assay. Recombinant hepc 20 was purified through Reverse-Phase HPLC column and characterized by Mass Spectrometry and amino acid sequencing. It also exhibited antibacterial activity against Staphylococcus aureus and Bacillus subtilis.