Integration of a reconstituted cell-free protein-synthesis system on a glass microchip

Recently, a cell-free protein synthesis system reconstituted solely from essential elements of the Escherichia coli translation system, termed protein synthesis using recombinant elements (PURE), has been widely used in synthetic biology to analyze fundamental life systems. Here, the system was integrated on a glass microchip system to construct a simple protein synthesis system. GFP template DNAs were immobilized on Sepharose microbeads by streptavidin-biotin binding. The beads were introduced into a Y-shaped microchannel in a glass microchip with a 10-μm height dam structure, and a PURE system reaction mixture was flowed through the microchannel. The recovered solutions had a higher fluorescent intensity than that of the reaction mixture before its introduction into the microchannel, thus verifying that GFP synthesis had been achieved. The microchip with DNA immobilized microbeads is reusable. This is advantageous over a conventional in vitro protein synthesis protocol requiring the preparation and addition of template DNA or mRNA into the reaction mixtures in aspect of simpleness and rapidness.