Skip to main content
Log in

Translational incorporation of multiple unnatural amino acids in a cell-free protein synthesis system

  • Research Paper
  • Published:
Biotechnology and Bioprocess Engineering Aims and scope Submit manuscript

Abstract

Nature uses 20 canonical amino acids as the standard building blocks of proteins; however, the incorporation of unnatural amino acids (Uaas) can endow polypeptide sequences with new structural and functional features. Although aminoacyl-tRNA synthetases (aaRSs) can accept an array of Uaas in place of their natural counterparts, Uaas generally are charged to tRNAs with substantially lower efficiencies. This particularly makes it difficult to incorporate multiple Uaas into a protein sequence. In this study, we discuss the use of a cell-free protein synthesis system as a versatile platform for the efficient incorporation of multiple Uaas into proteins. Taking advantage of the open nature of cell-free protein synthesis that allows flexible manipulation of its ingredients, we explored the application of Uaas in 10 mM range of concentrations to kinetically overcome the low affinity of aaRSs towards unnatural amino acids. Supplementation of recombinant aaRSs was also investigated to further increase the Uaa-tRNA pools. As a result, under the modified reaction conditions, as many as five different Uaas could be incorporated into a single protein without compromising the yield of protein synthesis.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

Refrerences

  1. Liu, C. C. and P. G. Schultz (2010) Adding new chemistries to the genetic code. Annu. Rev. Biochem. 79: 413–444.

    Article  CAS  Google Scholar 

  2. Bose, M., D. Groff, J. Xie, E. Brustad, and P. G. Schultz (2006) The incorporation of a photoisomerizable amino acid into proteins in E. coli. J. Am. Chem. Soc. 128: 388–389.

    Article  CAS  Google Scholar 

  3. Schultz, K. C., L. Supekova, Y. Ryu, J. Xie, R. Perera, and P. G. Schultz (2006) A genetically encoded infrared probe. J. Am. Chem. Soc. 128: 13984–13985.

    Article  CAS  Google Scholar 

  4. Tang, Y., G. Ghirlanda, W. A. Petka, T. Nakajima, W. F. DeGrado, and D. A. Tirrell (2001) Fluorinated coiled-coil proteins prepared in vivo display enhanced thermal and chemical stability. Angew. Chem. Int. Ed. 40: 1494–1496.

    Article  CAS  Google Scholar 

  5. Meng, H. and K. Kumar (2007) Antimicrobial activity and protease stability of peptides containing fluorinated amino acids. J. Am. Chem. Soc. 129: 15615–15622.

    Article  CAS  Google Scholar 

  6. Wang, F., W. Niu, J. Guo, and P. G. Schultz (2012) Unnatural amino acid mutagenesis of fluorescent proteins. Angew. Chem. Int. Ed. 51: 10132–10135.

    Article  CAS  Google Scholar 

  7. Hartman, M. C., K. Josephson, and J. W. Szostak (2006) Enzymatic aminoacylation of tRNA with unnatural amino acids. Proc. Natl. Acad. Sci. USA. 103: 4356–4361.

    Article  CAS  Google Scholar 

  8. Hartman, M. C., K. Josephson, C. W. Lin, and J. W. Szostak (2007) An expanded set of amino acid analogs for the ribosomal translation of unnatural peptides. PLoS ONE. 2: e9–2.

    Article  Google Scholar 

  9. Lepthien, S., L. Merkel, and N. Budisa (2010) In vivo double and triple labeling of proteins using synthetic amino acids. Angew. Chem. Int. Ed. 49: 5446–5450.

    Article  CAS  Google Scholar 

  10. Link, A. J. and D. A. Tirrell (2005) Reassignment of sense codons in vivo. Methods. 36: 291–298.

    Article  CAS  Google Scholar 

  11. Kiick, K. L., E. Saxon, D. A. Tirrell, and C. R. Bertozzi (2002) Incorporation of azides into recombinant proteins for chemoselective modification by the Staudinger ligation. Proc. Natl. Acad. Sci. USA. 99: 19–24.

    Article  CAS  Google Scholar 

  12. Bennett, B. D., E. H. Kimball, M. Gao, R. Osterhout, S. J. Van Dien, and J. D. Rabinowitz (2009) Absolute metabolite concentrations and implied enzyme active site occupancy in Escherichia coli. Nat. Biotechnol. 5: 593–599.

    CAS  Google Scholar 

  13. Minks, C., S. Alefelder, L. Moroder, R. Huber, and N. Budisa (2000) Towards new protein engineering: In vivo building and folding of protein shuttles for drug delivery and targeting by the selective pressure incorporation (SPI) method. Tetrahedron. 56: 9431–9442.

    Article  CAS  Google Scholar 

  14. Ahn, J. H., K. H. Lee, J. W. Shim, E. Y. Lee, and D. M. Kim (2013) Streamlined cell-free protein synthesis from sequence information. Biotechnol. Bioproc. Eng. 18: 1101–1108.

    Article  CAS  Google Scholar 

  15. Mathew, S., G. Shin, M. Shon, and H. Yun (2013) High throughput methods for ω-tramsaminases. Biotechnol. Bioproc. Eng. 18: 1–7.

    Article  CAS  Google Scholar 

  16. Josephson, K., M. C. Hartman, and J. W. Szostak (2005) Ribosomal synthesis of unnatural peptides. J. Am. Chem. Soc. 127: 11727–11735.

    Article  CAS  Google Scholar 

  17. Ozawa, K., M. J. Headlam, D. Mouradov, S. J. Watt, J. L. Beck, K. J. Rodgers, R. T. Dean, T. Huber, G. Otting, and N. E. Dixon (2005) Translational incorporation of L-3,4-dihydroxyphenylalanine into proteins. FEBS J. 272: 3162–3171.

    Article  CAS  Google Scholar 

  18. Stigers, D. J., Z. I. Watts, J. E. Hennessy, H. K. Kim, R. Martini, M. C. Taylor, K. Ozawa, J. W. Keillor, N. E. Dixon, and C. J. Easton (2011) Incorporation of chlorinated analogues of aliphatic amino acids during cell-free protein synthesis. Chem. Commun. 47: 1839–1841.

    Article  CAS  Google Scholar 

  19. Kim, T. W., J. W. Keum, I. S. Oh, C. Y. Choi., C. G. Park, and D. M. Kim (2006) Simple procedures for the construction of a robust and cost-effective cell-free protein synthesis system. J. Biotechnol. 126: 554–561.

    Article  CAS  Google Scholar 

  20. Kim, T. W., H. C. Kim, I. S. Oh, and D. M. Kim (2008) A highly efficient and economical cell-free protein synthesis system using the S12 extract of Escherichia coli. Biotechnol. Bioproc. Eng. 13: 464–469.

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

  22. Keum, J. W., J. H. Ahn, C. Y. Choi, K. H. Lee, Y. C. Kwon, and D. M. Kim (2006) The presence of a common downstream box enables the simultaneous expression of multiple proteins in an E. coli extract. Biochem. Biophys. Res. Commun. 350: 562–567.

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

  24. Ahn, J. H., M. Y. Hwang, I. S. Oh, K. M. Park, G. H. Hahn, C. Y. Choi, and D. M. Kim (2006) Preparation method for Escherichia coli S30 extracts completely dependent upon tRNA addition to catalyze cell-free protein synthesis. Biotechnol. Bioproc. Eng. 11: 420–424.

    Article  CAS  Google Scholar 

  25. Schagger, H. (2006) Tricine-SDS-PAGE. Nat. Protoc. 1: 16–22.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Dong-Myung Kim.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Oh, SJ., Lee, KH., Kim, HC. et al. Translational incorporation of multiple unnatural amino acids in a cell-free protein synthesis system. Biotechnol Bioproc E 19, 426–432 (2014). https://doi.org/10.1007/s12257-013-0849-4

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12257-013-0849-4

Keywords

Navigation