The research team “Synthetic Genomics”, led by Prof. TIANJingdong, has developed an on-chip gene synthesis technology, which integrates on a single microchip the synthesis of DNA oligonucleotides using inkjet printing, isothermal oligonucleotide amplification and parallel gene assembly. The corresponding paper entitled "Parallel on-chip gene synthesis and application to optimization of protein expression"was published in Nature-Biotechnology. (http://www.nature.com/nbt/journal/v29/n5/full/nbt.1847.html)

Low-cost, high-throughput gene synthesis and precise control of protein expression are of critical importance to synthetic biology and biotechnology. The integration of oligo synthesis and gene assembly on the same microchip facilitates automation and miniaturization.Oligos are synthesized on an embossed plastic microchip using a custom-made inkjet DNA microchip synthesizer.A mismatch-specific endonuclease is used for error correction, resulting in an error rate of ~0.19 errors per kb. Then this approach was applied to synthesize pools of thousands of codon-usage variants of lacZaand 74 challenging Drosophila protein antigens, which were then screened for expression in Escherichia coli. In one round of synthesis and screening, we obtained DNA sequences that were expressed at a wide range of levels, from zero to almost 60% of the total cell protein mass. This technology may facilitate systematic investigation of the molecular mechanisms of protein translation and the design, construction and evolution of macromolecular machines, metabolic networks and synthetic cells.