Collagen Binding Domain Fusion Proteins for Therapeutics: Fermentation and Isolation

Interest in the production of recombinant proteins consisting of collagen binding domain (CBD) fused to a bioactive material has increased due to the targeting / attachment capabilities of CBD.  For example, CBD fusions can be applied to reversing of bone density loss and repair of eardrum, specifically, by choosing an appropriate fusion partner (parathyroid hormone or epidermal growth factor).  The production of CBD fusions was examined using batch and fed batch culturing of Escherichia coli to express the fusion proteins, and affinity chromatography to isolate the final product.  Different medium formulations and induction strategies were tested in order to develop a production strategy lacking yeast extract or other difficult-to-validate materials, and various methods of recovery were verified to be effective.  Data indicated that high productivity of these novel CBD fusion proteins can be achieved for use during cancer treatment and tympanoplasty, respectively.