Conditions optimization for high level expression and purification of human recombinant consensus interferon (rh cIFN) and its characterization.

Recombinant human consensus interferon (rh-cIFN) is an artificially engineered interferon developed by recombining and reordering the protein sequences that exist in standard interferon. This recombination resulted in to a drug that has the potential to work better than natural, standard interferon. In present study we described optimized conditions for high level expression and recovery of biological active consensus interferon from inclusion bodies. A synthetic gene coding 166 amino acid of consensus interferon was cloned under T7 promoter. Escherichia coli strain BL21DE3Plys was used to transform expression construct. For high level expression, shake flask fermentation conditions were standardized. For isolation of inclusion bodies sonication method was optimized. Variety of chaotropic agents including guanidine hydrochloride, urea, SDS, and detergents were studied for solubilization of inclusion bodies. For re-naturation of solubilized denatured protein by dilution process, parameters of dilution factor, temperature and L-argine were optimized. One step chromatography method was developed for high yield purification of consensus interferon. Recombinant human cIFN was characterized by SDS-PAGE, western blot, HPLC. Purified protein has molecular weight of 19.5 kDa and specific activity was 2.0Χ108 as determined by cytopathic inhibition assay. This study concludes that by using optimized conditions, we obtained a yield of 100mg/L of biologically active rhcIFN, which is highest ever reported according to available data. This article is protected by copyright. All rights reserved.This article is protected by copyright. All rights reserved.