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Incorporation of azides into recombinant proteins for chemoselective modification by the Staudinger ligation

Kiick, Kristi L. and Saxon, Eliana and Tirrell, David A. and Bertozzi, Carolyn R. (2002) Incorporation of azides into recombinant proteins for chemoselective modification by the Staudinger ligation. Proceedings of the National Academy of Sciences of the United States of America, 99 (1). pp. 19-24. ISSN 0027-8424. PMCID PMC117506. doi:10.1073/pnas.012583299.

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The introduction of chemically unique groups into proteins by means of non-natural amino acids has numerous applications in protein engineering and functional studies. One method to achieve this involves the utilization of a non-natural amino acid by the cell's native translational apparatus. Here we demonstrate that a methionine surrogate, azidohomoalanine, is activated by the methionyl-tRNA synthetase of Escherichia coli and replaces methionine in proteins expressed in methionine-depleted bacterial cultures. We further show that proteins containing azidohomoalanine can be selectively modified in the presence of other cellular proteins by means of Staudinger ligation with triarylphosphine reagents. Incorporation of azide-functionalized amino acids into proteins in vivo provides opportunities for protein modification under native conditions and selective labeling of proteins in the intracellular environment.

Item Type:Article
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URLURL TypeDescription CentralArticle
Kiick, Kristi L.0000-0001-8587-0301
Tirrell, David A.0000-0003-3175-4596
Bertozzi, Carolyn R.0000-0003-4482-2754
Additional Information:© 2002 by the National Academy of Sciences Communicated by Ralph F. Hirschmann, University of Pennsylvania, Philadelphia, PA, October 31, 2001 (received for review August 15, 2001). Published online before print December 18, 2001, 10.1073/pnas.012583299 We acknowledge the generous donation of plasmids encoding MetRS from H. Jakubowski and Y. Mechulam and the assistance of J. Kua in modeling the azide-functionalized amino acids. This research was supported by the Office of Naval Research, Grant N00014–98-1–0605 and Order N00014–98-F-0402 through the U.S. Department of Energy under Contract DE-AC03–76SF00098, the National Institutes of Health (GM58867–01), the Polymers and Genetics Programs of the U.S. National Science Foundation, and the U.S. Army Research Office. K.L.K. thanks the U.S. Department of Defense for a National Defense Science and Engineering Graduate Fellowship. E.S. was supported by a Howard Hughes Medical Institute Predoctoral Fellowship. The Center for New Directions in Organic Synthesis is supported by Bristol-Myers Squibb as a supporting member. K.L.K. and E.S. contributed equally to this work. The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. §1734 solely to indicate this fact.
Funding AgencyGrant Number
Office of Naval Research (ONR)N00014–98-1–0605
Office of Naval Research (ONR)N00014–98-F-0402
Department of Energy (DOE)DE-AC03–76SF00098
Army Research Office (ARO)UNSPECIFIED
National Defense Science and Engineering Graduate (NDSEG) FellowshipUNSPECIFIED
Howard Hughes Medical Institute (HHMI)UNSPECIFIED
Bristol-Myers SquibbUNSPECIFIED
Issue or Number:1
PubMed Central ID:PMC117506
Record Number:CaltechAUTHORS:KIIpnas02
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:830
Deposited By: Archive Administrator
Deposited On:11 Oct 2005
Last Modified:08 Nov 2021 19:05

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