Physicochemical characterization of E. coli-derived human serum albumin and its comparison with the human plasma counterpart reveals it as a promising biosimilar.

Human serum albumin one of the most demanded proteins possess an array of clinical and biotechnological applications. Currently, the prime source for HSA production is the human blood which possesses the risk of pathogen contamination and is limited. Thus, there exists an indispensable need to promote non-animal derived HSA production. In the present work, we have exploited the opportunity and promoted the preparation of pathogen-free rHSA from the E. coli host which is blessed with numerous advantages like scalability, cost-effectiveness etc. Upon overcoming the difficulties to produce functional rHSA in E. coli, through engineering the biological system of protein folding in the cell, the E. coli-derived rHSA has been purified to homogeneity. Its detailed physicochemical characterization has been performed, by monitoring its conformational properties, secondary and tertiary structure elements, surface properties, ligand binding properties, stability issues etc. These parameters of the recombinant protein have been compared with the naturally occurring protein from the human source. The outcome of the comparison reveals that the recombinant protein resembles exactly the same as the natural one. Hence, we propose and promote that the E. coli-derived rHSA is an ideal biosimilar for human blood plasma-derived serum albumin.