Increasing the solubility of recombinant Glutathione S-transferase from Rutilus kutum using chaperone-based method in Escherichia coli

Attainment of soluble recombinant protein in high quantity is a critical demand in all types of biotechnology. Between the available general and protein-specific techniques used for enhancing the protein solubility, the co-expression of desired protein with molecular chaperones seems to be a proper solution to assist the folding of newly synthesized protein and reduce the inclusion bodies formation, however the effectiveness of different chaperones varies widely. In order to evaluate the efficiency of fish chaperones in increasing the solubility of recombinant proteins, cloning and simultaneous expression of Esox lucius Hsp70 (El-Hsp70) and the µ-class glutathione S-transferase from Rutilus kutum (Rk-GSTµ) was performed on E. coli host. In order to investigate the protein-protein interaction, the SDS-PAGE electrophoresis and measuring the specific activity of Rk-GSTµ was applied. Since the solubility and specific activity of Rk-GSTµ were increased in co-expressing cells, this work has provided another promising finding on the positive role of chaperones in enhancing the soluble content of expressed recombinant proteins.