All 34 proteins required for mRNA translation have been produced in a single culture using a new technique that could lead to the rapid assembly of pure protein synthesis machinery outside of living cells, according to researchers at UC Davis.
In a paper published earlier this week in Nature Chemical Biology, Fernando Villarreal and colleagues in Cheemeng Tan's lab in the department of biomedical engineering, engineered synthetic microbial consortia consisting of between 15 and 34 Escherichia coli strains to assemble the 34 proteins in a single culturing, lysis, and purification procedure.
The Tan lab engineered strains of Escherichia coli bacteria to produce the required proteins. By manipulating transcription rates, translation rates, and relative strain densities, the group found that they could induce the bacterial consortia to produce correct quantities of the translation machinery.
"I believe the work will open doors to fundamental improvement in the protein yield of pure cell-free transcription-translation systems and throughput of studying disease-relevant pathways outside of living cells," Tan said.
The team called their method TraMOS, for Translation Machinery One Shot. By reducing the time and cost associated with preparing multiprotein systems, the Tan lab's approach enables high-throughput applications of TraMOS without having to invest in additional purification equipment. Unlike existing approaches, they report that scientists can customize the expression and control of proteins using the TraMOS approach. Most labs that routinely perform protein purification already have the equipment to use the TraMOS approach. In addition, the microbial consortia-based approach may be generalized for the synthesis of other multiprotein systems, making it a potential game changer for high-throughput cell-free applications.
Image: E. coli bacteria tagged with different colors produced different mixtures of proteins. Together, the bacterial consortium makes all the proteins needed for mRNA translation/protein synthesis. The new method developed at UC Davis could speed development of cell-free biological systems. Image courtesy of Fernando Villarreal, UC Davis.