Construction and expression of a novel bioactive IFN-α2b/CM4 fusion protein in Escherichia coli

SummaryHuman interferon alpha2b (IFN-α2b) is a pleiotropic cytokine used for the treatment of various cancers. Antibacterial peptide CM4 is a small peptide that can strongly inhibit many kinds of bacteria, fungi, and tumor cells, but it does no harm to normal cells. Here, we describe a protein expression system for the production of IFN-α2b/CM4 fusion protein in insoluble form in Escherichia coli, coupled to an efficient dialysis refolding and histidine-tag purification protocol. The expressed IFN-α2b/CM4 fusion protein not only displays significantly improved antitumor activity, but also retains the antibacterial–antifungal activity of CM4.