Site-specific labeling of proteins with NMR-active unnatural amino acids

  • David H. Jones
  • Susan E. Cellitti
  • Xueshi Hao
  • Qiong Zhang
  • Michael Jahnz
  • Daniel Summerer
  • Peter G. Schultz
  • Tetsuo Uno
  • Bernhard H. Geierstanger


A large number of amino acids other than the canonical amino acids can now be easily incorporated in vivo into proteins at genetically encoded positions. The technology requires an orthogonal tRNA/aminoacyl-tRNA synthetase pair specific for the unnatural amino acid that is added to the media while a TAG amber or frame shift codon specifies the incorporation site in the protein to be studied. These unnatural amino acids can be isotopically labeled and provide unique opportunities for site-specific labeling of proteins for NMR studies. In this perspective, we discuss these opportunities including new photocaged unnatural amino acids, outline usage of metal chelating and spin-labeled unnatural amino acids and expand the approach to in-cell NMR experiments.


Site-specific labeling Unnatural amino acids Spin label Metal chelator In-cell NMR 



We thank Huiyong Hu for the synthesis of 15N-labeled o-NBTyr, and Hyun Soo Lee for samples of HQ-Ala.

Supplementary material

10858_2009_9365_MOESM1_ESM.docx (1.4 mb)
(DOCX 1454 kb)


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • David H. Jones
    • 1
  • Susan E. Cellitti
    • 1
  • Xueshi Hao
    • 1
  • Qiong Zhang
    • 1
  • Michael Jahnz
    • 2
  • Daniel Summerer
    • 2
  • Peter G. Schultz
    • 1
    • 2
  • Tetsuo Uno
    • 1
  • Bernhard H. Geierstanger
    • 1
  1. 1.Genomics Institute of the Novartis Research FoundationSan DiegoUSA
  2. 2.Department of Chemistry and the Skaggs Institute for Chemical BiologyThe Scripps Research InstituteLa JollaUSA

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