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Cell-free gene expression: an expanded repertoire of applications

Abstract

Cell-free biology is the activation of biological processes without the use of intact living cells. It has been used for more than 50 years across the life sciences as a foundational research tool, but a recent technical renaissance has facilitated high-yielding (grams of protein per litre), cell-free gene expression systems from model bacteria, the development of cell-free platforms from non-model organisms and multiplexed strategies for rapidly assessing biological design. These advances provide exciting opportunities to profoundly transform synthetic biology by enabling new approaches to the model-driven design of synthetic gene networks, the fast and portable sensing of compounds, on-demand biomanufacturing, building cells from the bottom up, and next-generation educational kits.

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Fig. 1: Timeline of cell-free gene expression systems.
Fig. 2: Cell-free gene expression for prototyping cellular mechanisms of transcription and translation.
Fig. 3: Cell-free systems for prototyping proteins and pathways.
Fig. 4: Building cells and synthetic biology education.
Fig. 5: Design of cell-free biosensors.
Fig. 6: Cell-free biomanufacturing platforms.
Fig. 7: The economics of cell-free gene expression.

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References

  1. Blow, J. J. & Laskey, R. A. Initiation of DNA replication in nuclei and purified DNA by a cell-free extract of Xenopus eggs. Cell 47, 577–587 (1986).

    CAS  PubMed  Google Scholar 

  2. Fuller, R. S., Kaguni, J. M. & Kornberg, A. Enzymatic replication of the origin of the Escherichia coli chromosome. Proc. Natl Acad. Sci. USA 78, 7370–7374 (1981).

    CAS  PubMed  Google Scholar 

  3. Preiss, T. & Hentze, M. W. Dual function of the messenger RNA cap structure in poly(A)-tail-promoted translation in yeast. Nature 392, 516–520 (1998).

    CAS  PubMed  Google Scholar 

  4. Nirenberg, M. W. & Matthaei, J. H. The dependence of cell-free protein synthesis in E. coli upon naturally occurring or synthetic polyribonucleotides. Proc. Natl Acad. Sci. USA 47, 1588–1602 (1961).

    CAS  PubMed  Google Scholar 

  5. Nirenberg, M. & Leder, P. RNA codewords and protein synthesis. The effect of trinucleotides upon the binding of sRNA to ribosomes. Science 145, 1399–1407 (1964).

    CAS  PubMed  Google Scholar 

  6. Carlson, E. D., Gan, R., Hodgman, C. E. & Jewett, M. C. Cell-free protein synthesis: applications come of age. Biotechnol. Adv. 30, 1185–1194 (2012).

    CAS  PubMed  Google Scholar 

  7. Hodgman, C. E. & Jewett, M. C. Cell-free synthetic biology: thinking outside the cell. Metab. Eng. 14, 261–269 (2012).

    CAS  PubMed  Google Scholar 

  8. Swartz, J. R. Expanding biological applications using cell-free metabolic engineering: an overview. Metab. Eng. 50, 156–172 (2018).

    CAS  PubMed  Google Scholar 

  9. Sun, Z. Z. et al. Protocols for implementing an Escherichia coli based TX-TL cell-free expression system for synthetic biology. J. Vis. Exp. 79, e50762 (2013).

    Google Scholar 

  10. Calhoun, K. A. & Swartz, J. R. An economical method for cell-free protein synthesis using glucose and nucleoside monophosphates. Biotechnol. Prog. 21, 1146–1153 (2005).

    CAS  PubMed  Google Scholar 

  11. Liu, D. V., Zawada, J. F. & Swartz, J. R. Streamlining Escherichia coli S30 extract preparation for economical cell-free protein synthesis. Biotechnol. Prog. 21, 460–465 (2005).

    CAS  PubMed  Google Scholar 

  12. Calhoun, K. A. & Swartz, J. R. Energizing cell-free protein synthesis with glucose metabolism. Biotechnol. Bioeng. 90, 606–613 (2005).

    CAS  PubMed  Google Scholar 

  13. Jewett, M. C., Calhoun, K. A., Voloshin, A., Wuu, J. J. & Swartz, J. R. An integrated cell-free metabolic platform for protein production and synthetic biology. Mol. Syst. Biol. 4, 220 (2008).

    PubMed  PubMed Central  Google Scholar 

  14. Wuu, J. J. & Swartz, J. R. High yield cell-free production of integral membrane proteins without refolding or detergents. Biochim. Biophys. Acta 1778, 1237–1250 (2008).

    CAS  PubMed  Google Scholar 

  15. Goerke, A. R. & Swartz, J. R. Development of cell-free protein synthesis platforms for disulfide bonded proteins. Biotechnol. Bioeng. 99, 351–367 (2008).

    CAS  PubMed  Google Scholar 

  16. Bundy, B. C., Franciszkowicz, M. J. & Swartz, J. R. Escherichia coli-based cell-free synthesis of virus-like particles. Biotechnol. Bioeng. 100, 28–37 (2008).

    CAS  PubMed  Google Scholar 

  17. Thoring, L., Dondapati, S. K., Stech, M., Wüstenhagen, D. A. & Kubick, S. High-yield production of “difficult-to-express” proteins in a continuous exchange cell-free system based on CHO cell lysates. Sci. Rep. 7, 11710 (2017).

    PubMed  PubMed Central  Google Scholar 

  18. Yin, G. & Swartz, J. R. Enhancing multiple disulfide bonded protein folding in a cell-free system. Biotechnol. Bioeng. 86, 188–195 (2004).

    CAS  PubMed  Google Scholar 

  19. Kelwick, R., Webb, A. J., MacDonald, J. T. & Freemont, P. S. Development of a Bacillus subtilis cell-free transcription-translation system for prototyping regulatory elements. Metab. Eng. 38, 370–381 (2016).

    CAS  PubMed  Google Scholar 

  20. Hodgman, C. E. & Jewett, M. C. Optimized extract preparation methods and reaction conditions for improved yeast cell-free protein synthesis. Biotechnol. Bioeng. 110, 2643–2654 (2013).

    CAS  PubMed  Google Scholar 

  21. Yim, S. S. et al. Multiplex transcriptional characterizations across diverse bacterial species using cell-free systems. Mol. Syst. Biol. 15, e8875 (2019).

    PubMed  PubMed Central  Google Scholar 

  22. Zubay, G. In vitro synthesis of protein in microbial systems. Annu. Rev. Genet. 7, 267–287 (1973).

    CAS  PubMed  Google Scholar 

  23. Kwon, Y.-C. & Jewett, M. C. High-throughput preparation methods of crude extract for robust cell-free protein synthesis. Sci. Rep. 5, 8663 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  24. Shrestha, P., Holland, T. M. & Bundy, B. C. Streamlined extract preparation for Escherichia coli-based cell-free protein synthesis by sonication or bead vortex mixing. Biotechniques 53, 163–174 (2012).

    CAS  PubMed  Google Scholar 

  25. Didovyk, A., Tonooka, T., Tsimring, L. & Hasty, J. Rapid and scalable preparation of bacterial lysates for cell-free gene expression. ACS Synth. Biol. 6, 2198–2208 (2017).

    CAS  PubMed  PubMed Central  Google Scholar 

  26. Kim, T.-W. et al. Simple procedures for the construction of a robust and cost-effective cell-free protein synthesis system. J. Biotechnol. 126, 554–561 (2006).

    CAS  PubMed  Google Scholar 

  27. Shimizu, Y. et al. Cell-free translation reconstituted with purified components. Nat. Biotechnol. 19, 751 (2001). The authors describe the first bottom-up reconstituted cell-free system in which all proteins necessary for in vitro protein synthesis are purified from separate batch cultures and mixed.

    CAS  PubMed  Google Scholar 

  28. Dopp, B. J. L., Tamiev, D. D. & Reuel, N. F. Cell-free supplement mixtures: elucidating the history and biochemical utility of additives used to support in vitro protein synthesis in E. coli extract. Biotechnol. Adv. 37, 246–258 (2019).

    CAS  PubMed  Google Scholar 

  29. Chiao, A. C., Murray, R. M. & Sun, Z. Z. Development of prokaryotic cell-free systems for synthetic biology. Preprint at bioRxiv https://doi.org/10.1101/048710 (2016).

  30. Moore, S. J. et al. Rapid acquisition and model-based analysis of cell-free transcription–translation reactions from nonmodel bacteria. Proc. Natl Acad. Sci. USA 115, E4340–E4349 (2018). This study demonstrates that biophysical parameters for transcription and translation in Bacillius megaterium can be obtained through very high-throughput cell-free experiments with fluorescent RNA and protein readouts.

    CAS  PubMed  Google Scholar 

  31. Karig, D. K., Iyer, S., Simpson, M. L. & Doktycz, M. J. Expression optimization and synthetic gene networks in cell-free systems. Nucleic Acids Res. 40, 3763–3774 (2012).

    CAS  PubMed  Google Scholar 

  32. Ahn, J.-H., Kang, T.-J. & Kim, D.-M. Tuning the expression level of recombinant proteins by modulating mRNA stability in a cell-free protein synthesis system. Biotechnol. Bioeng. 101, 422–427 (2008).

    CAS  PubMed  Google Scholar 

  33. Shin, J. & Noireaux, V. Efficient cell-free expression with the endogenous E. Coli RNA polymerase and sigma factor 70. J. Biol. Eng. 4, 8 (2010).

    PubMed  PubMed Central  Google Scholar 

  34. Halleran, A. D. & Murray, R. M. Cell-free and in vivo characterization of Lux, Las, and Rpa quorum activation systems in E. coli. ACS Synth. Biol. 7, 752–755 (2018).

    CAS  PubMed  Google Scholar 

  35. Chappell, J., Jensen, K. & Freemont, P. S. Validation of an entirely in vitro approach for rapid prototyping of DNA regulatory elements for synthetic biology. Nucleic Acids Res. 41, 3471–3481 (2013). The authors demonstrate a correspondence between the strength of ribosome-binding sites measured from in-cell and cell-free experiments.

    CAS  PubMed  PubMed Central  Google Scholar 

  36. Jayaraman, P. et al. Cell-free optogenetic gene expression system. ACS Synth. Biol. 7, 986–994 (2018).

    CAS  PubMed  Google Scholar 

  37. de los Santos, E. L., Meyerowitz, J. T., Mayo, S. L. & Murray, R. M. Engineering transcriptional regulator effector specificity using computational design and in vitro rapid prototyping: developing a vanillin sensor. ACS Synth. Biol. 5, 287–295 (2016).

    Google Scholar 

  38. Geertz, M., Shore, D. & Maerkl, S. J. Massively parallel measurements of molecular interaction kinetics on a microfluidic platform. Proc. Natl Acad. Sci. USA 109, 16540–16545 (2012).

    CAS  PubMed  Google Scholar 

  39. Swank, Z., Laohakunakorn, N. & Maerkl, S. J. Cell-free gene-regulatory network engineering with synthetic transcription factors. Proc. Natl Acad. Sci. USA 161, 5892–5901 (2019).

    Google Scholar 

  40. Senoussi, A. et al. Quantitative characterization of translational riboregulators using an in vitro transcription–translation system. ACS Synth. Biol. 7, 1269–1278 (2018).

    CAS  PubMed  Google Scholar 

  41. Espah Borujeni, A., Mishler, D. M., Wang, J., Huso, W. & Salis, H. M. Automated physics-based design of synthetic riboswitches from diverse RNA aptamers. Nucleic Acids Res. 44, 1–13 (2016).

    PubMed  Google Scholar 

  42. Saito, H. et al. Synthetic translational regulation by an L7Ae–kink-turn RNP switch. Nat. Chem. Biol. 6, 71–78 (2009).

    PubMed  Google Scholar 

  43. Siegal-Gaskins, D., Tuza, Z. A., Kim, J., Noireaux, V. & Murray, R. M. Gene circuit performance characterization and resource usage in a cell-free “breadboard”. ACS Synth. Biol. 3, 416–425 (2014).

    CAS  PubMed  Google Scholar 

  44. Niederholtmeyer, H., Xu, L. & Maerkl, S. J. Real-time mRNA measurement during an in vitro transcription and translation reaction using binary probes. ACS Synth. Biol. 2, 411–417 (2013).

    CAS  PubMed  Google Scholar 

  45. Sun, Z. Z., Yeung, E., Hayes, C. A., Noireaux, V. & Murray, R. M. Linear DNA for rapid prototyping of synthetic biological circuits in an Escherichia coli based TX-TL cell-free system. ACS Synth. Biol. 3, 387–397 (2014). This study demonstrates the use of linear DNA templates in a CFE system by protecting templates with lambda phage protein gamS, with the aim of correlating promoter strengths measured in cells and in vitro.

    CAS  PubMed  Google Scholar 

  46. Sitaraman, K. et al. A novel cell-free protein synthesis system. J. Biotechnol. 110, 257–263 (2004).

    CAS  PubMed  Google Scholar 

  47. Marshall, R. et al. Short DNA containing χ sites enhances DNA stability and gene expression in E. coli cell-free transcription-translation systems. Biotechnol. Bioeng. 114, 2137–2141 (2017).

    CAS  PubMed  PubMed Central  Google Scholar 

  48. Dittrich, P. S., Jahnz, M. & Schwille, P. A new embedded process for compartmentalized cell-free protein expression and online detection in microfluidic devices. ChemBioChem 6, 811–814 (2005).

    CAS  PubMed  Google Scholar 

  49. Khnouf, R., Beebe, D. J. & Fan, Z. H. Cell-free protein expression in a microchannel array with passive pumping. Lab Chip 9, 56–61 (2009).

    CAS  PubMed  Google Scholar 

  50. Khnouf, R., Olivero, D., Jin, S. & Fan, Z. H. Miniaturized fluid array for high-throughput protein expression. Biotechnol. Prog. 26, 1590–1596 (2010).

    CAS  PubMed  Google Scholar 

  51. Khnouf, R., Chapman, B. D. & Fan, Z. H. Fabrication optimization of a miniaturized array device for cell-free protein synthesis. Electrophoresis 32, 3101–3107 (2011).

    CAS  PubMed  Google Scholar 

  52. Fallah-Araghi, A., Baret, J.-C., Ryckelynck, M. & Griffiths, A. D. A completely in vitro ultrahigh-throughput droplet-based microfluidic screening system for protein engineering and directed evolution. Lab Chip 12, 882–891 (2012).

    CAS  PubMed  Google Scholar 

  53. Griffiths, A. D. & Tawfik, D. S. Directed evolution of an extremely fast phosphotriesterase by in vitro compartmentalization. EMBO J. 22, 24–35 (2003).

    CAS  PubMed  PubMed Central  Google Scholar 

  54. Tawfik, D. S. & Griffiths, A. D. Man-made cell-like compartments for molecular evolution. Nat. Biotechnol. 16, 652 (1998).

    CAS  PubMed  Google Scholar 

  55. Courtois, F. et al. An integrated device for monitoring time-dependent in vitro expression from single genes in picolitre droplets. ChemBioChem 9, 439–446 (2008).

    CAS  PubMed  Google Scholar 

  56. Zhang, Y. et al. Accurate high-throughput screening based on digital protein synthesis in a massively parallel femtoliter droplet array. Sci. Adv. 5, eaav8185 (2019).

    PubMed  PubMed Central  Google Scholar 

  57. He, M. & Taussig, M. J. Single step generation of protein arrays from DNA by cell-free expression and in situ immobilization (PISA method). Nucleic Acids Res. 29, e73 (2001).

    CAS  PubMed  PubMed Central  Google Scholar 

  58. He, M. & Taussig, M. J. DiscernArray™ technology: a cell-free method for the generation of protein arrays from PCR DNA. J. Immunol. Methods 274, 265–270 (2003).

    CAS  PubMed  Google Scholar 

  59. He, M. et al. Printing protein arrays from DNA arrays. Nat. Methods 5, 175 (2008).

    CAS  PubMed  Google Scholar 

  60. Heyman, Y., Buxboim, A., Wolf, S. G., Daube, S. S. & Bar-Ziv, R. H. Cell-free protein synthesis and assembly on a biochip. Nat. Nanotechnol. 7, 374 (2012).

    CAS  PubMed  Google Scholar 

  61. Karzbrun, E., Tayar, A. M., Noireaux, V. & Bar-Ziv, R. H. Programmable on-chip DNA compartments as artificial cells. Science 345, 829–832 (2014).

    CAS  PubMed  Google Scholar 

  62. Fan, J. et al. Multi-dimensional studies of synthetic genetic promoters enabled by microfluidic impact printing. Lab Chip 17, 2198–2207 (2017).

    CAS  PubMed  PubMed Central  Google Scholar 

  63. Noireaux, V., Bar-Ziv, R. & Libchaber, A. Principles of cell-free genetic circuit assembly. Proc. Natl Acad. Sci. USA 100, 12672–12677 (2003).

    CAS  PubMed  Google Scholar 

  64. Garamella, J., Marshall, R., Rustad, M. & Noireaux, V. The all E. coli TX-TL Toolbox 2.0: a platform for cell-free synthetic biology. ACS Synth. Biol. 5, 344–355 (2016). The authors describe a platform for CFE that includes linear expression templates, semicontinuous reactions, genetic cascade circuits, bacteriophage assembly and encapsulation within liposomes.

    CAS  PubMed  Google Scholar 

  65. Shin, J. & Noireaux, V. An E. coli cell-free expression toolbox: application to synthetic gene circuits and artificial cells. ACS Synth. Biol. 1, 29–41 (2012).

    CAS  PubMed  Google Scholar 

  66. Guo, S., Yeung, E. & Murray, R. M. Implementation and system identification of a phosphorylation-based insulator in a cell-free transcription-translation system. Preprint at bioRxiv https://doi.org/10.1101/122606 (2017).

  67. Takahashi, M. K. et al. Characterizing and prototyping genetic networks with cell-free transcription–translation reactions. Methods 86, 60–72 (2015).

    CAS  PubMed  Google Scholar 

  68. Takahashi, M. K. et al. Rapidly characterizing the fast dynamics of RNA genetic circuitry with cell-free transcription–translation (TX-TL) systems. ACS Synth. Biol. 4, 503–515 (2015). The authors show that synthetic RNA parts can be assembled in a CFE reaction with predictable behaviour, enabling the computation of complex logic operations.

    CAS  PubMed  Google Scholar 

  69. Hu, C. Y., Takahashi, M. K., Zhang, Y. & Lucks, J. B. Engineering a functional small RNA negative autoregulation network with model-guided design. ACS Synth. Biol. 7, 1507–1518 (2018).

    PubMed  Google Scholar 

  70. Westbrook, A. et al. Distinct timescales of RNA regulators enable the construction of a genetic pulse generator. Biotechnol. Bioeng. 116, 1139–1151 (2019).

    CAS  PubMed  Google Scholar 

  71. Guo, S. & Murray, R. M. Construction of incoherent feedforward loop circuits in a cell-free system and in cells. ACS Synth. Biol. 8, 606–610 (2019).

    CAS  PubMed  Google Scholar 

  72. Hori, Y., Kantak, C., Murray, R. M. & Abate, A. R. Cell-free extract based optimization of biomolecular circuits with droplet microfluidics. Lab Chip 17, 3037–3042 (2017).

    CAS  PubMed  Google Scholar 

  73. Niederholtmeyer, H., Stepanova, V. & Maerkl, S. J. Implementation of cell-free biological networks at steady state. Proc. Natl Acad. Sci. USA 110, 15985–15990 (2013).

    CAS  PubMed  Google Scholar 

  74. Niederholtmeyer, H. et al. Rapid cell-free forward engineering of novel genetic ring oscillators. eLife 4, e09771 (2015).

    PubMed  PubMed Central  Google Scholar 

  75. Nagaraj, V. H., Greene, J. M., Sengupta, A. M. & Sontag, E. D. Translation inhibition and resource balance in the TX-TL cell-free gene expression system. Synth. Biol. 2, ysx005 https://doi.org/10.1093/synbio/ysx005 (2017).

    CAS  Google Scholar 

  76. Nishimura, K., Tsuru, S., Suzuki, H. & Yomo, T. Stochasticity in gene expression in a cell-sized compartment. ACS Synth. Biol. 4, 566–576 (2015).

    CAS  PubMed  Google Scholar 

  77. Borkowski, O. et al. Cell-free prediction of protein expression costs for growing cells. Nat. Commun. 9, 1457 (2018).

    PubMed  PubMed Central  Google Scholar 

  78. Karzbrun, E., Shin, J., Bar-Ziv, R. H. & Noireaux, V. Coarse-grained dynamics of protein synthesis in a cell-free system. Phys. Rev. Lett. 106, 048104 (2011). The authors investigate the rate determinants of gene expression in an E. coli CFE system and obtain rate parameters consistent with a coarse-grained ordinary differential equation model for cell-free transcription and translation.

    PubMed  Google Scholar 

  79. Wiegand, D. J., Lee, H. H., Ostrov, N. & Church, G. M. Establishing a cell-free Vibrio natriegens expression system. ACS Synth. Biol. 7, 2475–2479 (2018).

    CAS  PubMed  Google Scholar 

  80. Des Soye, B. J., Davidson, S. R., Weinstock, M. T., Gibson, D. G. & Jewett, M. C. Establishing a high-yielding cell-free protein synthesis platform derived from Vibrio natriegens. ACS Synth. Biol. 7, 2245–2255 (2018).

    CAS  PubMed  Google Scholar 

  81. Failmezger, J., Scholz, S., Blombach, B. & Siemann-Herzberg, M. Cell-free protein synthesis from fast-growing Vibrio natriegens. Front. Microbiol. 9, 1146–1146 (2018).

    PubMed  PubMed Central  Google Scholar 

  82. Wang, H., Li, J. & Jewett, M. C. Development of a Pseudomonas putida cell-free protein synthesis platform for rapid screening of gene regulatory elements. Synth. Biol. 3, ysy003 (2018).

    CAS  Google Scholar 

  83. Li, J., Wang, H., Kwon, Y. C. & Jewett, M. C. Establishing a high yielding Streptomyces-based cell-free protein synthesis system. Biotechnol. Bioeng. 114, 1343–1353 (2017).

    CAS  PubMed  Google Scholar 

  84. Moore, S. J., Lai, H.-E., Needham, H., Polizzi, K. M. & Freemont, P. S. Streptomyces venezuelae TX-TL – a next generation cell-free synthetic biology tool. Biotechnol. J. 12, https://doi.org/10.1002/biot.201600678 (2017).

    Google Scholar 

  85. Li, J., Wang, H. & Jewett, M. C. Expanding the palette of Streptomyces-based cell-free protein synthesis systems with enhanced yields. Biochem. Eng. J. 130, 29–33 (2018).

    CAS  Google Scholar 

  86. Wick, S. et al. PERSIA for direct fluorescence measurements of transcription, translation, and enzyme activity in cell-free systems. ACS Synth. Biol. 8, 1010–1025 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  87. Marshall, R. & Noireaux, V. Quantitative modelling of transcription and translation of an all-E. coli cell-free system. Sci. Rep. 9, 11980 (2019).

    PubMed  PubMed Central  Google Scholar 

  88. Underwood, K. A., Swartz, J. R. & Puglisi, J. D. Quantitative polysome analysis identifies limitations in bacterial cell-free protein synthesis. Biotechnol. Bioeng. 91, 425–435 (2005).

    CAS  PubMed  Google Scholar 

  89. Nieß, A., Failmezger, J., Kuschel, M., Siemann-Herzberg, M. & Takors, R. Experimentally validated model enables debottlenecking of in vitro protein synthesis and identifies a control shift under in vivo conditions. ACS Synth. Biol. 6, 1913–1921 (2017).

    PubMed  Google Scholar 

  90. Lavickova, B. & Maerkl, S. J. A simple, robust, and low-cost method to produce the pure cell-free system. ACS Synth. Biol. 8, 455–462 (2019).

    CAS  PubMed  Google Scholar 

  91. Vilkhovoy, M. et al. Sequence specific modelling of E. coli cell-free protein synthesis. ACS Synth. Biol. 7, 1844–1857 (2018).

    CAS  PubMed  Google Scholar 

  92. Doerr, A. et al. Modelling cell-free RNA and protein synthesis with minimal systems. Phys. Biol. 16, 025001 (2019).

    CAS  PubMed  Google Scholar 

  93. Kigawa, T., Muto, Y. & Yokoyama, S. Cell-free synthesis and amino acid-selective stable isotope labelling of proteins for NMR analysis. J. Biomol. NMR 6, 129–134 (1995).

    CAS  PubMed  Google Scholar 

  94. Torizawa, T., Shimizu, M., Taoka, M., Miyano, H. & Kainosho, M. Efficient production of isotopically labeled proteins by cell-free synthesis: a practical protocol. J. Biomol. NMR 30, 311–325 (2004).

    CAS  PubMed  Google Scholar 

  95. Takeda, M. & Kainosho, M. Protein NMR Techniques (eds Alexander Shekhtman & David S. Burz) 71–84 (Humana Press, 2012).

  96. Narumi, R. et al. Cell-free synthesis of stable isotope-labeled internal standards for targeted quantitative proteomics. Synth. Syst. Biotechnol. 3, 97–104 (2018).

    PubMed  PubMed Central  Google Scholar 

  97. Narumi, R. et al. Mass spectrometry-based absolute quantification reveals rhythmic variation of mouse circadian clock proteins. Proc. Natl Acad. Sci. USA 113, E3461–E3467 (2016).

    CAS  PubMed  Google Scholar 

  98. Oza, J. P. et al. Robust production of recombinant phosphoproteins using cell-free protein synthesis. Nat. Commun. 6, 8168 (2015).

    PubMed  PubMed Central  Google Scholar 

  99. Kightlinger, W. et al. Design of glycosylation sites by rapid synthesis and analysis of glycosyltransferases. Nat. Chem. Biol. 14, 627–635 (2018).

    CAS  PubMed  Google Scholar 

  100. Kightlinger, W. et al. A cell-free biosynthesis platform for modular construction of protein glycosylation pathways. Nat. Commun. https://doi.org/10.1038/s41467-019-12024-9 (2019).

  101. Valderrama-Rincon, J. D. et al. An engineered eukaryotic protein glycosylation pathway in Escherichia coli. Nat. Chem. Biol. 8, 434–436 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  102. Wacker, M. et al. N-linked glycosylation in Campylobacter jejuni and its functional transfer into E. coli. Science 298, 1790–1793 (2002).

    CAS  PubMed  Google Scholar 

  103. Schoborg, J. A. et al. A cell-free platform for rapid synthesis and testing of active oligosaccharyltransferases. Biotechnol. Bioeng. 115, 739–750 (2018).

    CAS  PubMed  Google Scholar 

  104. Stouthamer, A. H. A theoretical study on the amount of ATP required for synthesis of microbial cell material. Antonie van Leeuwenhoek 39, 545–565 (1973).

    CAS  PubMed  Google Scholar 

  105. Kim, D.-M. & Swartz, J. R. Prolonging cell-free protein synthesis with a novel ATP regeneration system. Biotechnol. Bioeng. 66, 180–188 (1999).

    CAS  PubMed  Google Scholar 

  106. Kim, D.-M. & Swartz, J. R. Regeneration of adenosine triphosphate from glycolytic intermediates for cell-free protein synthesis. Biotechnol. Bioeng. 74, 309–316 (2001).

    CAS  PubMed  Google Scholar 

  107. Kim, D.-M. & Swartz, J. R. Oxalate improves protein synthesis by enhancing ATP supply in a cell-free system derived from Escherichia coli. Biotechnol. Lett. 22, 1537–1542 (2000).

    CAS  Google Scholar 

  108. Kim, D.-M. & Swartz, J. R. Prolonging cell-free protein synthesis by selective reagent additions. Biotechnol. Prog. 16, 385–390 (2000).

    CAS  PubMed  Google Scholar 

  109. Jewett, M. C. & Swartz, J. R. Substrate replenishment extends protein synthesis with an in vitro translation system designed to mimic the cytoplasm. Biotechnol. Bioeng. 87, 465–471 (2004).

    CAS  PubMed  Google Scholar 

  110. Karim, A. S. & Jewett, M. C. A cell-free framework for rapid biosynthetic pathway prototyping and enzyme discovery. Metab. Eng. 36, 116–126 (2016). The authors demonstrate a mix-and-match approach for variants of enzymes used for cell-free butanol synthesis that can be applied towards pathway optimization in cells.

    CAS  PubMed  Google Scholar 

  111. Karim, A. S., Heggestad, J. T., Crowe, S. A. & Jewett, M. C. Controlling cell-free metabolism through physiochemical perturbations. Metab. Eng. 45, 86–94 (2018).

    CAS  PubMed  Google Scholar 

  112. Kelwick, R. et al. Cell-free prototyping strategies for enhancing the sustainable production of polyhydroxyalkanoates bioplastics. Synth. Biol. 3, ysy016 (2018).

    CAS  Google Scholar 

  113. Dudley, Q. M., Anderson, K. C. & Jewett, M. C. Cell-free mixing of Escherichia coli crude extracts to prototype and rationally engineer high-titer mevalonate synthesis. ACS Synth. Biol. 5, 1578–1588 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  114. Casini, A. et al. A pressure test to make 10 molecules in 90 days: external evaluation of methods to engineer biology. J. Am. Chem. Soc. 140, 4302–4316 (2018).

    CAS  PubMed  Google Scholar 

  115. Kay, J. E. & Jewett, M. C. Lysate of engineered Escherichia coli supports high-level conversion of glucose to 2,3-butanediol. Metab. Eng. 32, 133–142 (2015).

    CAS  PubMed  Google Scholar 

  116. Dudley, Q. M., Nash, C. J. & Jewett, M. C. Cell-free biosynthesis of limonene using enzyme-enriched Escherichia coli lysates. Synth. Biol. 4, ysz003 (2019).

    CAS  Google Scholar 

  117. Wu, Y. Y. et al. System-level studies of a cell-free transcription-translation platform for metabolic engineering. Preprint at bioRxiv https://doi.org/10.1101/172007 (2017).

  118. Karim, A. S. et al. In vitro prototyping and rapid optimization of biosynthetic enzymes for cellular design. Preprint at bioRxiv https://doi.org/10.1101/685768 (2019).

  119. Arévalo-Pinzón, G. et al. Self-assembling functional programmable protein array for studying protein-protein interactions in malaria parasites. Malar. J. 17, 270 (2018).

    PubMed  PubMed Central  Google Scholar 

  120. Woodrow, K. A. & Swartz, J. R. A sequential expression system for high-throughput functional genomic analysis. Proteomics 7, 3870–3879 (2007).

    CAS  PubMed  Google Scholar 

  121. Marshall, R. et al. Rapid and scalable characterization of CRISPR technologies using an E. coli cell-free transcription-translation system. Mol. Cell 69, 146–157 (2018). The authors demonstrate that CRISPR systems can be effectively studied using CFE, including determining the preferred protospacer-adjacent motif sites for uncharacterized Cas nucleases and for screening anti-CRISPR proteins.

    CAS  PubMed  PubMed Central  Google Scholar 

  122. Watters, K. E., Fellmann, C., Bai, H. B., Ren, S. M. & Doudna, J. A. Systematic discovery of natural CRISPR-Cas12a inhibitors. Science 362, 236–239 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  123. Dubuc, E. et al. Cell-free microcompartmentalised transcription–translation for the prototyping of synthetic communication networks. Curr. Opin. Biotechnol. 58, 72–80 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  124. Forster, A. C. & Church, G. M. Towards synthesis of a minimal cell. Mol. Syst. Biol. 2, 45 (2006).

    PubMed  PubMed Central  Google Scholar 

  125. Shin, J., Jardine, P. & Noireaux, V. Genome replication, synthesis, and assembly of the bacteriophage T7 in a single cell-free reaction. ACS Synth. Biol. 1, 408–413 (2012).

    CAS  PubMed  Google Scholar 

  126. Rustad, M., Eastlund, A., Jardine, P. & Noireaux, V. Cell-free TXTL synthesis of infectious bacteriophage T4 in a single test tube reaction. Synth. Biol. 3, ysy002 (2018).

    CAS  Google Scholar 

  127. Noireaux, V. & Libchaber, A. A vesicle bioreactor as a step towards an artificial cell assembly. Proc. Natl Acad. Sci. USA 101, 17669–17674 (2004).

    CAS  PubMed  Google Scholar 

  128. Aufinger, L. & Simmel, F. C. Artificial gel-based organelles for spatial organization of cell-free gene expression reactions. Angew. Chem. Int. Ed. 57, 17245–17248 (2018).

    CAS  Google Scholar 

  129. Thiele, J. et al. DNA-functionalized hydrogels for confined membrane-free in vitro transcription/translation. Lab Chip 14, 2651–2656 (2014).

    CAS  PubMed  Google Scholar 

  130. Sokolova, E. et al. Enhanced transcription rates in membrane-free protocells formed by coacervation of cell lysate. Proc. Natl Acad. Sci. USA 110, 11692–11697 (2013).

    CAS  PubMed  Google Scholar 

  131. Dora Tang, T. Y., van Swaay, D., deMello, A., Ross Anderson, J. L. & Mann, S. In vitro gene expression within membrane-free coacervate protocells. Chem. Commun. 51, 11429–11432 (2015).

    CAS  Google Scholar 

  132. Zhou, X., Wu, H., Cui, M., Lai, S. N. & Zheng, B. Long-lived protein expression in hydrogel particles: towards artificial cells. Chem. Sci. 9, 4275–4279 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  133. Deshpande, S. et al. Spatiotemporal control of coacervate formation within liposomes. Nat. Commun. 10, 1800 (2019).

    PubMed  PubMed Central  Google Scholar 

  134. Berhanu, S., Ueda, T. & Kuruma, Y. Artificial photosynthetic cell producing energy for protein synthesis. Nat. Commun. 10, 1325 (2019).

    PubMed  PubMed Central  Google Scholar 

  135. Adamala, K. P., Martin-Alarcon, D. A., Guthrie-Honea, K. R. & Boyden, E. S. Engineering genetic circuit interactions within and between synthetic minimal cells. Nat. Chem. 9, 431–439 (2016).

    PubMed  PubMed Central  Google Scholar 

  136. Peruzzi, J. A., Jacobs, M. L., Vu, T. Q. & Kamat, N. P. Barcoding biological reactions with DNA-functionalized vesicles. Angew. Chem. Int. Ed. Engl. https://doi.org/10.1002/ange.201911544 (2019).

    Google Scholar 

  137. Vogele, K. et al. Towards synthetic cells using peptide-based reaction compartments. Nat. Commun. 9, 3862 (2018).

    PubMed  PubMed Central  Google Scholar 

  138. Stark, J. C. et al. BioBits™ bright: a fluorescent synthetic biology education kit. Sci. Adv. 4, eaat5107 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  139. Albayrak, C., Jones, K. C. & Swartz, J. R. Broadening horizons and teaching basic biology through cell-free synthesis of green fluorescent protein in a high school laboratory course. J. Sci. Educ. Technol. 22, 963–973 (2013).

    CAS  Google Scholar 

  140. Huang, A. et al. BioBits™ explorer: a modular synthetic biology education kit. Sci. Adv. 4, eaat5105 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  141. Stark, J. C. et al. BioBitsTM health: classroom activities exploring engineering, biology, and human health with fluorescent readouts. ACS Synth. Biol. 8, 1001–1009 (2019).

    CAS  PubMed  Google Scholar 

  142. Collias, D., Marshall, R., Collins, S. P., Beisel, C. L. & Noireaux, V. An educational module to explore CRISPR technologies with a cell-free transcription-translation system. Synth. Biol. 4, ysz005 (2019).

    CAS  Google Scholar 

  143. Pardee, K. et al. Paper-based synthetic gene networks. Cell 159, 940–954 (2014). The authors show that CFE reactions can maintain functionality upon freeze-drying onto a paper support, with applicability for point-of-care sensing, and show an example using a toehold switch sensor that detects Ebola virus.

    CAS  PubMed  PubMed Central  Google Scholar 

  144. Verosloff, M., Chappell, J., Perry, K. L., Thompson, J. R. & Lucks, J. B. PLANT-Dx: a molecular diagnostic for point-of-use detection of plant pathogens. ACS Synth. Biol. 8, 902–905 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  145. Phillips, E. A., Moehling, T. J., Bhadra, S., Ellington, A. D. & Linnes, J. C. Strand displacement probes combined with isothermal nucleic acid amplification for instrument-free detection from complex samples. Anal. Chem. 90, 6580–6586 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  146. Jiang, Y. S. et al. Robust strand exchange reactions for the sequence-specific, real-time detection of nucleic acid amplicons. Anal. Chem. 87, 3314–3320 (2015).

    CAS  PubMed  Google Scholar 

  147. Li, B., Chen, X. & Ellington, A. D. Adapting enzyme-free DNA circuits to the detection of loop-mediated isothermal amplification reactions. Anal. Chem. 84, 8371–8377 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  148. Pardee, K. et al. Rapid, low-cost detection of Zika virus using programmable biomolecular components. Cell 165, 1255–1266 (2016).

    CAS  PubMed  Google Scholar 

  149. Ma, D., Shen, L., Wu, K., Diehnelt, C. W. & Green, A. A. Low-cost detection of norovirus using paper-based cell-free systems and synbody-based viral enrichment. Synth. Biol. 3, ysy018 (2018).

    CAS  Google Scholar 

  150. Takahashi, M. K. et al. A low-cost paper-based synthetic biology platform for analysing gut microbiota and host biomarkers. Nat. Commun. 9, 3347 (2018).

    PubMed  PubMed Central  Google Scholar 

  151. Green, A. A., Silver, P. A., Collins, J. J. & Yin, P. Toehold switches: de novo-designed regulators of gene expression. Cell 159, 925–939 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  152. Heim, A., Grumbach, I. M., Zeuke, S. & Top, B. Highly sensitive detection of gene expression of an intronless gene: amplification of mRNA, but not genomic DNA by nucleic acid sequence based amplification (NASBA). Nucleic Acids Res. 26, 2250–2251 (1998).

    CAS  PubMed  PubMed Central  Google Scholar 

  153. Piepenburg, O., Williams, C. H., Stemple, D. L. & Armes, N. A. DNA detection using recombination proteins. PLOS Biol. 4, e204 (2006).

    PubMed  PubMed Central  Google Scholar 

  154. Myhrvold, C. et al. Field-deployable viral diagnostics using CRISPR-Cas13. Science 360, 444–448 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  155. Kawaguchi, T., Chen, Y. P., Norman, R. S. & Decho, A. W. Rapid screening of quorum-sensing signal n-acyl homoserine lactones by an in vitro cell-free assay. Appl. Environ. Microbiol. 74, 3667–3671 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

  156. Wen, K. Y. et al. A cell-free biosensor for detecting quorum sensing molecules in P. aeruginosa-infected respiratory samples. ACS Synth. Biol. 6, 2293–2301 (2017).

    CAS  PubMed  Google Scholar 

  157. Liu, X. et al. Design of a transcriptional biosensor for the portable, on-demand detection of cyanuric acid. Preprint at bioRxiv https://doi.org/10.1101/736355 (2019).

  158. Pandi, A., Grigoras, I., Borkowski, O. & Faulon, J. L. Optimizing cell-free biosensors to monitor enzymatic production. ACS Synth. Biol. 8, 1952–1957 (2019).

    CAS  PubMed  Google Scholar 

  159. Thavarajah, W. et al. Point-of-use detection of environmental fluoride via a cell-free riboswitch-based biosensor. Preprint at bioRxiv https://doi.org/10.1101/712844 (2019).

  160. Alam, K. K. et al. Rapid, low-cost detection of water contaminants using regulated in vitro transcription. Preprint at bioRxiv https://doi.org/10.1101/619296 (2019).

  161. Salehi, A. S. M. et al. Cell-free protein synthesis approach to biosensing hTRβ-specific endocrine disruptors. Anal. Chem. 89, 3395–3401 (2017).

    CAS  PubMed  Google Scholar 

  162. Gräwe, A. et al. A paper-based, cell-free biosensor system for the detection of heavy metals and date rape drugs. PLOS ONE 14, e0210940 (2019).

    PubMed  PubMed Central  Google Scholar 

  163. Silverman, A. D., Akova, U., Alam, K. K., Jewett, M. C. & Lucks, J. B. Design and optimization of a cell-free atrazine biosensor. Preprint at bioRxiv https://doi.org/10.1101/779827 (2019).

  164. Voyvodic, P. L. et al. Plug-and-play metabolic transducers expand the chemical detection space of cell-free biosensors. Nat. Commun. 10, 1697 (2019).

    PubMed  PubMed Central  Google Scholar 

  165. McNerney, M. P. et al. Point-of-care biomarker quantification enabled by sample-specific calibration. Sci. Adv. 5, eaax4473 (2019).

    PubMed  PubMed Central  Google Scholar 

  166. Cayley, S., Lewis, B. A., Guttman, H. J. & Record, M. T. Characterization of the cytoplasm of Escherichia coli K-12 as a function of external osmolarity: implications for protein-DNA interactions in vivo. J. Mol. Biol. 222, 281–300 (1991).

    CAS  PubMed  Google Scholar 

  167. Kim, D. M. & Swartz, J. R. Efficient production of a bioactive, multiple disulfide-bonded protein using modified extracts of Escherichia coli. Biotechnol. Bioeng. 85, 122–129 (2004).

    CAS  PubMed  Google Scholar 

  168. Zawada, J. F. et al. Microscale to manufacturing scale-up of cell-free cytokine production — a new approach for shortening protein production development timelines. Biotechnol. Bioeng. 108, 1570–1578 (2011). This study is the most complete example in the literature of commercial scaling of CFE reactions (up to 100 liters), which demonstrated a high degree of linearity in the production of cytokines.

    CAS  PubMed  PubMed Central  Google Scholar 

  169. Yin, G. et al. Aglycosylated antibodies and antibody fragments produced in a scalable in vitro transcription-translation system. mAbs 4, 217–225 (2012).

    PubMed  PubMed Central  Google Scholar 

  170. Kanter, G. et al. Cell-free production of scFv fusion proteins: an efficient approach for personalized lymphoma vaccines. Blood 109, 3393–3399 (2007).

    CAS  PubMed  PubMed Central  Google Scholar 

  171. Martin, R. W. et al. Development of a CHO-based cell-free platform for synthesis of active monoclonal antibodies. ACS Synth. Biol. 6, 1370–1379 (2017).

    CAS  PubMed  Google Scholar 

  172. Stech, M. et al. Cell-free synthesis of functional antibodies using a coupled in vitro transcription-translation system based on CHO cell lysates. Sci. Rep. 7, 12030 (2017).

    CAS  PubMed  PubMed Central  Google Scholar 

  173. Timm, A. C., Shankles, P. G., Foster, C. M., Doktycz, M. J. & Retterer, S. T. Towards microfluidic reactors for cell-free protein synthesis at the point-of-care. Small 12, 810–817 (2016).

    CAS  PubMed  Google Scholar 

  174. Burgenson, D. et al. Rapid recombinant protein expression in cell-free extracts from human blood. Sci. Rep. 8, 9569 (2018).

    PubMed  PubMed Central  Google Scholar 

  175. Yang, J.-P., Cirico, T., Katzen, F., Peterson, T. C. & Kudlicki, W. Cell-free synthesis of a functional G protein-coupled receptor complexed with nanometer scale bilayer discs. BMC Biotechnol. 11, 57 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  176. Yang, J. et al. Rapid expression of vaccine proteins for B cell lymphoma in a cell-free system. Biotechnol. Bioeng. 89, 503–511 (2005).

    CAS  PubMed  Google Scholar 

  177. Salehi, A. S. et al. Cell-free protein synthesis of a cytotoxic cancer therapeutic: onconase production and a just-add-water cell-free system. Biotechnol. J. 11, 274–281 (2016).

    CAS  PubMed  Google Scholar 

  178. Smith, M. T., Berkheimer, S. D., Werner, C. J. & Bundy, B. C. Lyophilized Escherichia coli-based cell-free systems for robust, high-density, long-term storage. Biotechniques 56, 186–193 (2014).

    CAS  PubMed  Google Scholar 

  179. Pardee, K. et al. Portable, on-demand biomolecular manufacturing. Cell 167, 248–259.e12 (2016). In this work, the authors show that freeze-dried cell-free reactions can be used to produce therapeutic proteins, including antimicrobial peptides and antibody fragments, on-demand at the point of need.

    CAS  PubMed  Google Scholar 

  180. Karig, D. K., Bessling, S., Thielen, P., Zhang, S. & Wolfe, J. Preservation of protein expression systems at elevated temperatures for portable therapeutic production. J. R. Soc. Interface 14, 20161039 (2017).

    PubMed  PubMed Central  Google Scholar 

  181. Stark, J. C. et al. On-demand, cell-free biomanufacturing of conjugate vaccines at the point-of-care. Preprint at bioRxiv https://doi.org/10.1101/681841 (2019).

  182. Wilding, K. M. et al. Endotoxin-free E. coli-based cell-free protein synthesis: pre-expression endotoxin removal approaches for on-demand cancer therapeutic production. Biotechnol. J. 14, e1800271 (2019).

    PubMed  Google Scholar 

  183. Sullivan, C. J. et al. A cell-free expression and purification process for rapid production of protein biologics. Biotechnol. J. 11, 238–248 (2016).

    CAS  PubMed  Google Scholar 

  184. Adiga, R. et al. Point-of-care production of therapeutic proteins of good-manufacturing-practice quality. Nat. Biomed. Eng. 2, 675–686 (2018).

    CAS  PubMed  Google Scholar 

  185. Boles, K. S. et al. Digital-to-biological converter for on-demand production of biologics. Nat. Biotechnol. 35, 672 (2017).

    CAS  PubMed  Google Scholar 

  186. Hong, S. H. et al. Cell-free protein synthesis from a release factor 1 deficient Escherichia coli activates efficient and multiple site-specific nonstandard amino acid incorporation. ACS Synth. Biol. 3, 398–409 (2014).

    CAS  PubMed  Google Scholar 

  187. Hong, S. H. et al. Improving cell-free protein synthesis through genome engineering of Escherichia coli lacking release factor 1. ChemBioChem 16, 844–853 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  188. Martin, R. W. et al. Cell-free protein synthesis from genomically recoded bacteria enables multisite incorporation of noncanonical amino acids. Nat. Commun. 9, 1203 (2018).

    PubMed  PubMed Central  Google Scholar 

  189. Albayrak, C. & Swartz, J. R. Cell-free co-production of an orthogonal transfer RNA activates efficient site-specific non-natural amino acid incorporation. Nucleic Acids Res. 41, 5949–5963 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  190. Cui, Z., Wu, Y., Mureev, S. & Alexandrov, K. Oligonucleotide-mediated tRNA sequestration enables one-pot sense codon reassignment in vitro. Nucleic Acids Res. 46, 6387–6400 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  191. Groff, D. et al. Engineering towards a bacterial “endoplasmic reticulum” for the rapid expression of immunoglobulin proteins. mAbs 6, 671–678 (2014).

    PubMed  PubMed Central  Google Scholar 

  192. Zimmerman, E. S. et al. Production of site-specific antibody–drug conjugates using optimized non-natural amino acids in a cell-free expression system. Bioconjug. Chem. 25, 351–361 (2014).

    CAS  PubMed  Google Scholar 

  193. Tarui, H., Imanishi, S. & Hara, T. A novel cell-free translation/glycosylation system prepared from insect cells. J. Biosci. Bioeng. 90, 508–514 (2000).

    CAS  PubMed  Google Scholar 

  194. Rothblatt, J. A. & Meyer, D. I. Secretion in yeast: reconstitution of the translocation and glycosylation of α-factor and invertase in a homologous cell-free system. Cell 44, 619–628 (1986).

    CAS  PubMed  Google Scholar 

  195. Zemella, A. et al. Cell-free protein synthesis as a novel tool for directed glycoengineering of active erythropoietin. Sci. Rep. 8, 8514 (2018).

    PubMed  PubMed Central  Google Scholar 

  196. Guarino, C. & DeLisa, M. P. A prokaryote-based cell-free translation system that efficiently synthesizes glycoproteins. Glycobiology 22, 596–601 (2012).

    CAS  PubMed  Google Scholar 

  197. Jaroentomeechai, T. et al. Single-pot glycoprotein biosynthesis using a cell-free transcription-translation system enriched with glycosylation machinery. Nat. Commun. 9, 2686 (2018). The authors demonstrate that oligosaccharyltransferases pre-expressed in a host strain can be used to perform site-specific glycosylation on target proteins in E. coli cell-free systems which lack native glycosylation machinery.

    PubMed  PubMed Central  Google Scholar 

  198. Maurer, K.-H. Detergent proteases. Curr. Opin. Biotechnol. 15, 330–334 (2004).

    CAS  PubMed  Google Scholar 

  199. Caschera, F. & Noireaux, V. Synthesis of 2.3 mg/ml of protein with an all Escherichia coli cell-free transcription–translation system. Biochimie 99, 162–168 (2014).

    CAS  PubMed  Google Scholar 

  200. Shrestha, P., Smith, M. T. & Bundy, B. C. Cell-free unnatural amino acid incorporation with alternative energy systems and linear expression templates. N. Biotechnol. 31, 28–34 (2014).

    CAS  PubMed  Google Scholar 

  201. Bujara, M., Schümperli, M., Billerbeck, S., Heinemann, M. & Panke, S. Exploiting cell-free systems: implementation and debugging of a system of biotransformations. Biotechnol. Bioeng. 106, 376–389 (2010).

    CAS  PubMed  Google Scholar 

  202. Bujara, M., Schümperli, M., Pellaux, R., Heinemann, M. & Panke, S. Optimization of a blueprint for in vitro glycolysis by metabolic real-time analysis. Nat. Chem. Biol. 7, 271 (2011).

    CAS  PubMed  Google Scholar 

  203. Bujara, M. & Panke, S. In silico assessment of cell-free systems. Biotechnol. Bioeng. 109, 2620–2629 (2012).

    CAS  PubMed  Google Scholar 

  204. Miguez, A., McNerney, M. & Styczynski, M. Metabolic profiling of Escherichia coli-based cell-free expression systems for process optimization. Ind. Eng. Chem. Res. https://doi.org/10.1021/acs.iecr.9b03565 (2019).

    CAS  Google Scholar 

  205. Panthu, B. et al. Cell-free protein synthesis enhancement from real-time NMR metabolite kinetics: redirecting energy fluxes in hybrid RRL systems. ACS Synth. Biol. 7, 218–226 (2018).

    CAS  PubMed  Google Scholar 

  206. Foshag, D. et al. The E. coli S30 lysate proteome: a prototype for cell-free protein production. N. Biotechnol. 40(Pt B), 245–260 (2018).

    CAS  PubMed  Google Scholar 

  207. Garenne, D., Beisel, C. L. & Noireaux, V. Characterization of the all-E. coli transcription-translation system myTXTL by mass spectrometry. Rapid Commun. Mass Spectrom. 33, 1036–1048 (2019).

    CAS  PubMed  Google Scholar 

  208. Cole, S. D. et al. Quantification of interlaboratory cell-free protein synthesis variability. ACS Synth. Biol. 8, 2080–2091 (2019).

    CAS  PubMed  Google Scholar 

  209. Michel-Reydellet, N., Calhoun, K. & Swartz, J. Amino acid stabilization for cell-free protein synthesis by modification of the Escherichia coli genome. Metab. Eng. 6, 197–203 (2004).

    CAS  PubMed  Google Scholar 

  210. Michel-Reydellet, N., Woodrow, K. & Swartz, J. Increasing PCR fragment stability and protein yields in a cell-free system with genetically modified Escherichia coli extracts. J. Mol. Microbiol. Biotechnol. 9, 26–34 (2005).

    CAS  PubMed  Google Scholar 

  211. Jewett, M. C. & Swartz, J. R. Mimicking the Escherichia coli cytoplasmic environment activates long-lived and efficient cell-free protein synthesis. Biotechnol. Bioeng. 86, 19–26 (2004).

    CAS  PubMed  Google Scholar 

  212. Spirin, A., Baranov, V., Ryabova, L., Ovodov, S. & Alakhov, Y. A continuous cell-free translation system capable of producing polypeptides in high yield. Science 242, 1162–1164 (1988).

    CAS  PubMed  Google Scholar 

  213. Kim, D.-M. & Choi, C.-Y. A semicontinuous prokaryotic coupled transcription/translation system using a dialysis membrane. Biotechnol. Prog. 12, 645–649 (1996).

    CAS  PubMed  Google Scholar 

  214. Chalfie, M., Tu, Y., Euskirchen, G., Ward, W. & Prasher, D. Green fluorescent protein as a marker for gene expression. Science 263, 802–805 (1994).

    CAS  PubMed  Google Scholar 

  215. Pédelacq, J.-D., Cabantous, S., Tran, T., Terwilliger, T. C. & Waldo, G. S. Engineering and characterization of a superfolder green fluorescent protein. Nat. Biotechnol. 24, 79–88 (2006).

    PubMed  Google Scholar 

  216. Silverman, A., Kelley-Loughnane, N., Lucks, J. B. & Jewett, M. C. Deconstructing cell-free extract preparation for in vitro activation of transcriptional genetic circuitry. ACS Synth. Biol. 8, 403–414 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

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Acknowledgements

The authors would like to acknowledge members of the Jewett and Lucks Labs for helpful discussions. They also specifically thank R. Murray, J. Swartz, K. Pardee, P. Freemont, J. Collins, and J. Lucks for discussions and input. M.C.J. acknowledges support from the Army Research Office Grants W911NF-16-1-0372, W911NF-19-1-0298 and W911NF-18-1-0200; National Science Foundation Grant MCB-1716766, the Air Force Research Laboratory Center of Excellence Grant FA8650-15-2-5518, the Defense Threat Reduction Agency Grant HDTRA1-15-10052/P00001, the Department of Energy Grant DE-SC0018249, the DOE Joint Genome Institute, the DARPA 1000 Molecules Program HR0011-15-C-0084, the Office of Energy Efficiency and Renewable Energy Grant DE-EE0008343, the Human Frontiers Science Program Grant RGP0015/2017, the National Institutes of Health Grant 1U19AI142780-01, the David and Lucile Packard Foundation, and the Camille Dreyfus Teacher-Scholar Program. A.D.S. was supported in part by the National Institutes of Health Training Grant (T32GM008449) through Northwestern University’s Biotechnology Training Program. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of Air Force Research Laboratory, Air Force Office of Scientific Research, DARPA, Defense Threat Reduction Agency or the U.S. Government.

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Nature Reviews Genetics thanks E. Strychalski and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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M.C.J. has a financial interest in SwiftScale Biologics and Design Pharmaceuticals Inc. M.C.J.’s interests are reviewed and managed by Northwestern University in accordance with their conflict of interest policies. All other authors declare no conflicts of interest.

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Supplementary information

Glossary

Breadboarding

The modular assembly of electronic circuits by combining well-characterized components (for example, resistors, voltage sources) onto a plastic board; the term has been co-opted for synthetic biology to describe the assembly of genetic regulatory networks.

Logic gate

An electronic component that can compute a basic Boolean binary operation (for example, AND, OR, NOT).

Sigma factors

The accessory protein components that form the holo bacterial RNA polymerase capable of transcription initiation.

Retroactivity

An effect where downstream effectors cause a genetic load on upstream components of a multicomponent metabolic or genetic network.

Ring oscillator

A genetic circuit in which three species are interchanged (A → B → C → A) and their concentrations vary with a fixed period.

Protospacer-adjacent motif

(PAM). A 3′-recognition sequence for CRISPR–Cas proteins that determines the sites of RNA-mediated DNA cleavage.

Liposomes

Spherical compartment composed of phospholipid bilayers that spontaneously forms when fatty acids aggregate in water.

Coacervation

Liquid–liquid phase separation that occurs in polymer solutions.

Giant unilamellar vesicles

Liposomes containing a single bilayer with a size in the order of a whole cell or larger (radius ~1–100 µm).

Molecular beacon

A nucleic acid duplex in which one strand is covalently linked to a fluorophore and the other is linked to a fluorescence quencher, so that fluorescence is only observed upon disruption of the duplex.

Toehold switch

A genetic regulator in which mRNA translation is inhibited by sterically blocking a ribosome-binding site with a complementary strand of mRNA in the 5′ untranslated region, which can only be translationally competent if the duplex is disrupted by a complementary (trigger) strand.

Xenobiotic

Molecules that are not produced in any known natural biological systems.

Microsomes

Small vesicles originating from the endoplasmic reticulum when cells are sheared and centrifuged.

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Silverman, A.D., Karim, A.S. & Jewett, M.C. Cell-free gene expression: an expanded repertoire of applications. Nat Rev Genet 21, 151–170 (2020). https://doi.org/10.1038/s41576-019-0186-3

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