Quentin Dudley, a postdoc at the Earlham Institute, did a PhD in the Jewett lab (Northwestern University, Illinois) focused on the use of cell-free systems for the reconstitution of metabolic pathways and bioproduction of monoterpenes. Now he is using an OpenPlant Fund Award to establish cell-free platforms for protein synthesis in Norwich. Read more about this work below, and on www.biomaker.org
As part of this project he is recruiting participants for a workshop on cell-free protein synthesis to be held in mid-June in Norwich. It is an opportunity to try to express your favourite protein using a low-cost, high-throughput platform. Download the poster for details and contact quentin.dudley@earlham.ac.uk for details and questions.
Cell-free protein synthesis
Cell-free protein synthesis (CFPS) uses crude lysates of E. coli, wheat germ, and other organisms to recapitulate transcription and translation in a test tube (Carlson et al., 2012). This enables protein production at higher throughput, shorter timescales, and simpler troubleshooting compared to expression in cells. While CFPS has several pros/cons, it is particularly powerful when testing many different protein variants/mutations with an output assay that works directly in the crude cell-free reaction.
While CFPS is getting easier to implement, buying commercial kits can get expensive and troubleshooting the first time can be challenging. In response, I’m leading a project sponsored by the OpenPlant fund to establish an in-house E. coli CFPS system (~£1 / rxn) at Norwich/Cambridge and want to compare it to a commercial wheat germ kit (£12 / rxn) for expressing proteins. We are testing a range of different proteins from various plants. If you have an interesting protein you’d like to try expressing in a cell-free system, please contact quentin.dudley@earlham.ac.uk for details!)
I’ve previously worked with CFPS as a graduate student with Michael Jewett at Northwestern University. The Jewett lab is working to develop new CFPS platforms using yeast (S. cerevisiae), chloroplasts, and CHO cells. They also are improving existing E. coli-based systems to synthesize “tricky” proteins that require complex folding environments (membrane proteins, antibodies) or contain nonstandard amino acids. During my time in the lab, I used CFPS to manufacture enzyme homologs which could then be combined to prototype metabolic pathways, for example biosynthesis of monoterpenoids.
It is a very exciting time for cell-free systems. Protein yields have increased to 2 mg/mL and a commercial company (Sutro Biopharma) has reported reaction volumes at 100 L (Zawada et al., 2011). Additionally, cell-free reactions can be freeze-dried on paper and retain full activity; several groups are using this feature to develop on-demand pharmaceuticals or simple, color-changing diagnostics for diseases such as Zika virus (Pardee et al., 2016). As this cell-free technology matures, its flexibility and programmability make it an attractive opportunity for Biomaker projects and future applications will be limited only by the creativity of researchers and developers.
REFERENCES
Carlson, E. D., Gan, R., Hodgman, C. E., & Jewett, M. C. (2012). Cell-free protein synthesis: applications come of age. Biotechnology Advances, 30(5), 1185-1194.
Zawada, J. F., Yin, G., Steiner, A. R., Yang, J., Naresh, A., Roy, S. M., ... & Murray, C. J. (2011). Microscale to manufacturing scale‐up of cell‐free cytokine production—a new approach for shortening protein production development timelines. Biotechnology and Bioengineering, 108(7), 1570-1578.
Pardee, K., Green, A. A., Takahashi, M. K., Braff, D., Lambert, G., Lee, J. W., ... & Collins, J.J. (2016). Rapid, low-cost detection of Zika virus using programmable biomolecular components. Cell, 165(5), 1255-1266.