Microbial platform cells for synthetic biology

In synthetic biology, biological systems are considered assemblies of modules, parts, and devices that are controlled by synthetic circuits. In biotechnological aspects, the area of synthetic biology includes (1) the synthesis of genes, genomes, and life; (2) the synthesis of new metabolic pathways; (3) modular engineering of proteins; and (4) the development of biosensors, most of which can be verified in synthetic cells. To achieve the various goals of synthetic biology, we need to know how to design and engineer microbial synthetic cells properly. To this end, there have been frequent discussions of chassis cells, which may be used in versatile ways. We need to define the meaning of chassis cells clearly and determine how to choose and produce microbial platform cells for industrial applications in the future. In this chapter, we summarize (1) the constituents of synthetic cells, (2) the current progress of development of conventional platform cells, and (3) the development of new cellular platforms based on extremophiles.