Gene expression engineering

Abstract

Cellular Systems can become platforms for Chemical production. Over the last four years, over 50 biopharmaceuticals have been approved for production, ranging in scope from hormones, enzymes, fusion proteins, antibodies, and vaccines. However, each of these applications-whether chemicals or pharmaceuticals, requires both a host organism and tools to engineer pathways in this chosen organism. The cellular hosts for these processes range in scope and complexity to include bacterial systems like Escherichia coli, yeast systems like Saccharomyces cerevisiae, and a variety of mammalian cell systems. To accomplish these production goals, it is necessary to control gene expression (especially of heterologous genes and pathways). This chapter will evaluate methods for controlling gene expression in the context of heterologous genes, endogenous genes, pathway expression and provide insight into new paradigms for flux control through gene expression circuits. A focus of this chapter will be on the various synthetic tools available for gene expression control. Although these basic principles are broadly applicable to multiple organisms, the predominant focus of this chapter will be on microbial systems, particularly E. coli and S. cerevisiae.