Advances in heterologous protein expression strategies in yeast and insect systems

The production of recombinant proteins has very high commercial and therapeutic values, especially with the increasing need for immune therapeutics and vaccines. However, none of the expression hosts can guarantee high yields of recombinant products. The eukaryotic expression system, yeast and insect cell lines, with easily accessible genetic tools, rapid growth, high cell density, and simple and inexpensive culture media, offer a better alternative to bacterial and mammalian cell expression systems. Moreover, they are harnessed to achieve a greater yield of heterologous protein with proper post-translational modifications with better protein quality due to their conserved cellular and metabolic processes to humans and other mammals. In this chapter, we discuss the established and emerging synthetic biology tools for engineered strain development of yeast and advances made towards the insect cell lines and baculovirus expression vectors that have been successfully used to express difficult-to-express proteins over the last couple of decades.