Cell-Free Protein Synthesis: Pros and Cons of Prokaryotic and Eukaryotic Systems

Abstract

From its start as a small-scale in vitro system to study fundamental translation processes, cell-free protein synthesis quickly rose to become a potent platform for the high-yield production of proteins. In contrast to classical in vivo protein expression, cell-free systems do not need time-consuming cloning steps, and the open nature provides easy manipulation of reaction conditions as well as high-throughput potential. Especially for the synthesis of difficult to express proteins, such as toxic and transmembrane proteins, cell-free systems are of enormous interest. The modification of the genetic code to incorporate non-canonical amino acids into the target protein in particular provides enormous potential in biotechnology and pharmaceutical research and is in the focus of many cell-free projects. Many sophisticated cell-free systems for manifold applications have been established. This review describes the recent advances in cell-free protein synthesis and details the expanding applications in this field. Recombinant protein production is essential for both research and therapy. Simple and flexible technologies for efficient high-throughput synthesis are needed. In the last decade, cell-free protein synthesis has emerged as a new source for various protein classes, including membrane, cytosolic, and even toxic proteins.