Strategies to improve the expression and solubility of recombinant proteins in E. coli

With the development of recombinant DNA technology in the 1980s, the heterologous expression of proteins has emerged as a valuable tool for researchers and pharmaceutical scientists, as it is generally challenging to obtain satisfactory yields from natural sources. Several prokaryotic and eukaryotic systems, including bacteria, yeast, insect, and mammalian platforms, have been developed to produce native-like proteins of an organism on a laboratory-scale and industrial-scale settings. E. coli has been the most widely used bacteria for the production of recombinant proteins due to its low cost, well-established cellular biochemistry and genetics, rapid growth, and good productivity, and it has become the most popular expression platform. However, optimizing the protocols for adequate expression and solubility remains a major disadvantage of this system. In this chapter, we discuss the approaches and methodologies to optimize the protein expression and solubility in E. coli and examine the troubleshooting practices for obtaining large quantities of soluble and stable recombinant proteins.