Production of Recombinant Human Hybrid Ferritin with Heavy Chain and Light Chain in Escherichia coli and its Characterization

Background: Natural human ferritin generally contains 24 subunits with different ratios of heavy chain to light chain, and the ratio of both subunits varies depending on tissue distribution and pathological conditions. However, the production of recombinant hybrid ferritin with both subunits is more challenging. Objective: This study aimed to prepare the recombinant hybrid ferritin for prokaryotic expression and characterize its structure and physicochemical properties. Methods: A prokaryotic expression vector of pACYCDuet-1 harboring the two individual genes of human ferritin heavy chain and light chain (FTH/FTL-pACYCDuet-1) was constructed and transfected into Escherichia coli bacteria. Then the genes were co-induced by IPTG to express. Results: The ferritin was purified by hydrophobic interaction chromatography combining size exclusion chromatography and verified by mass spectrometry and characterized by spectral and morphological analysis. Conclusion: FTH and FTL subunits were successfully co-assembled into a hybrid ferritin nanoparticle (rhFTH/L). The structure of rhFTH/L was demonstrated highly ordered and fairly compact. Besides, the hybrid rhFTH/L nanoparticle was shown more sensitive to thermal stress and reduced stability when compared with that of both individual rhFTH and rhFTL.