Synthetic Biology: A New Frontier

Synthetic biology applies engineering principles to living cells and organisms. It builds on the understanding of DNA molecular biology (Chap. ) and biotechnology (Chap. ) in using genetic tools to engineer synthetic cellular systems to produce products and understanding. We can use an analogy of electrical circuits in the way cellular systems integrate their biochemical machinery. The chapter will illustrate, through examples, how systems can be designed to produce specific products or outcomes. Plant-derived artemisinin used in malaria treatment is difficult to consistently supply the quantities required by manufacturers, so synthetic biology is used in yeast (Saccharomyces cerevisiae). In the process, three major strategies enable a synthetic pathway for the production of artemisinic acid. Another engineered plant product is leghemoglobin used in laboratory foods. Synthetic biology can also be used to produce industrial products and microbes with diverse function. Directed evolution is an important tool in synthetic biology that can be used in improving the efficiency of enzymes as catalysts for a variety of purposes—industry, environment, and medicine. Another tool for protein engineering is the use of unnatural amino acids that enable a greater range of properties for a protein. As synthetic biology advances, more complex gene circuits that can be programmed into the cell are being developed. An example is MultiFate, which uses artificial transcription factors.