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Zhang Y, Park KY, Suazo KF, Distefano MD. Recent progress in enzymatic protein labelling techniques and their applications. Chem Soc Rev 2018; 47:9106-9136. [PMID: 30259933 PMCID: PMC6289631 DOI: 10.1039/c8cs00537k] [Citation(s) in RCA: 156] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Protein-based conjugates are valuable constructs for a variety of applications. Conjugation of proteins to fluorophores is commonly used to study their cellular localization and the protein-protein interactions. Modification of therapeutic proteins with either polymers or cytotoxic moieties greatly enhances their pharmacokinetics or potency. To label a protein of interest, conventional direct chemical reaction with the side-chains of native amino acids often yields heterogeneously modified products. This renders their characterization complicated, requires difficult separation steps and may impact protein function. Although modification can also be achieved via the insertion of unnatural amino acids bearing bioorthogonal functional groups, these methods can have lower protein expression yields, limiting large scale production. As a site-specific modification method, enzymatic protein labelling is highly efficient and robust under mild reaction conditions. Significant progress has been made over the last five years in modifying proteins using enzymatic methods for numerous applications, including the creation of clinically relevant conjugates with polymers, cytotoxins or imaging agents, fluorescent or affinity probes to study complex protein interaction networks, and protein-linked materials for biosensing. This review summarizes developments in enzymatic protein labelling over the last five years for a panel of ten enzymes, including sortase A, subtiligase, microbial transglutaminase, farnesyltransferase, N-myristoyltransferase, phosphopantetheinyl transferases, tubulin tyrosin ligase, lipoic acid ligase, biotin ligase and formylglycine generating enzyme.
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Affiliation(s)
- Yi Zhang
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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2
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Abstract
The binding between biotin and streptavidin or avidin is one of the strongest known non-covalent biological interactions. The (strept)avidin-biotin interaction has been widely used for decades in biological research and biotechnology. Therefore labeling of purified proteins by biotin is a powerful way to achieve protein capture, immobilization, and functionalization, as well as multimerizing or bridging molecules. Chemical biotinylation often generates heterogeneous products, which may have impaired function. Enzymatic biotinylation with E. coli biotin ligase (BirA) is highly specific in covalently attaching biotin to the 15 amino acid AviTag peptide, giving a homogeneous product with high yield. AviTag can conveniently be added genetically at the N-terminus, C-terminus, or in exposed loops of a target protein. We describe here procedures for AviTag insertion by inverse PCR, purification of BirA fused to glutathione-S-transferase (GST-BirA) from E. coli, BirA biotinylation of purified protein, and gel-shift analysis by SDS-PAGE to quantify the extent of biotinylation.
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Affiliation(s)
- Michael Fairhead
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
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Dougherty DA, Van Arnam EB. In vivo incorporation of non-canonical amino acids by using the chemical aminoacylation strategy: a broadly applicable mechanistic tool. Chembiochem 2014; 15:1710-20. [PMID: 24990307 DOI: 10.1002/cbic.201402080] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Indexed: 01/05/2023]
Abstract
We describe a strategy for incorporating non-canonical amino acids site-specifically into proteins expressed in living cells, involving organic synthesis to chemically aminoacylate a suppressor tRNA, protein expression in Xenopus oocytes, and monitoring protein function, primarily by electrophysiology. With this protocol, a very wide range of non-canonical amino acids can be employed, allowing both systematic structure-function studies and the incorporation of reactive functionalities. Here, we present an overview of the methodology and examples meant to illustrate the versatility and power of the method as a tool for investigating protein structure and function.
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Affiliation(s)
- Dennis A Dougherty
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125 (USA).
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4
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Ieong KW, Pavlov MY, Kwiatkowski M, Forster AC, Ehrenberg M. Inefficient Delivery but Fast Peptide Bond Formation of Unnatural l-Aminoacyl-tRNAs in Translation. J Am Chem Soc 2012; 134:17955-62. [DOI: 10.1021/ja3063524] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ka-Weng Ieong
- Department of Cell and Molecular
Biology, Uppsala University, Husargatan
3, Box 596, Uppsala
75124, Sweden
| | - Michael Y. Pavlov
- Department of Cell and Molecular
Biology, Uppsala University, Husargatan
3, Box 596, Uppsala
75124, Sweden
| | - Marek Kwiatkowski
- Department of Cell and Molecular
Biology, Uppsala University, Husargatan
3, Box 596, Uppsala
75124, Sweden
| | - Anthony C. Forster
- Department of Cell and Molecular
Biology, Uppsala University, Husargatan
3, Box 596, Uppsala
75124, Sweden
| | - Måns Ehrenberg
- Department of Cell and Molecular
Biology, Uppsala University, Husargatan
3, Box 596, Uppsala
75124, Sweden
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5
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Pantoja R, Rodriguez EA, Dibas MI, Dougherty DA, Lester HA. Single-molecule imaging of a fluorescent unnatural amino acid incorporated into nicotinic receptors. Biophys J 2010; 96:226-37. [PMID: 19134478 DOI: 10.1016/j.bpj.2008.09.034] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Accepted: 09/29/2008] [Indexed: 10/21/2022] Open
Abstract
We report on the first, to our knowledge, successful detection of a fluorescent unnatural amino acid (fUAA), Lys(BODIPYFL), incorporated into a membrane protein (the muscle nicotinic acetylcholine receptor, nAChR) in a living cell. Xenopus oocytes were injected with a frameshift-suppressor tRNA, amino-acylated with Lys(BODIPYFL) and nAChR (alpha/beta19'GGGU/gamma/delta) mRNAs. We measured fluorescence from oocytes expressing nAChR beta19'Lys(BODIPYFL), using time-resolved total internal reflection fluorescence microscopy. Under conditions of relatively low receptor density (<0.1 receptors/microm(2)), we observed puncta with diffraction-limited profiles that were consistent with the point-spread function of our microscope. Furthermore, diffraction-limited puncta displayed step decreases in fluorescence intensity, consistent with single-molecule photobleaching. The puncta densities agreed with macroscopic ACh-induced current densities, showing that the fUAA was incorporated, and that receptors were functional. Dose-response relations for the nAChR beta19'Lys(BODIPYFL) receptors were similar to those for wild-type receptors. We also studied nAChR beta19'Lys(BODIPYFL) receptors labeled with alpha-bungarotoxin monoconjugated with Alexa488 (alphaBtxAlexa488). The nAChR has two alphaBtx binding sites, and puncta containing the Lys(BODIPYFL) labeled with alphaBtxAlexa488 yielded the expected three discrete photobleaching steps. We also performed positive control experiments with a nAChR containing enhanced green fluorescent protein in the gamma-subunit M3-M4 loop, which confirmed our nAChR beta19'Lys(BODIPYFL) measurements. Thus, we report on the cell-based single-molecule detection of nAChR beta19'Lys(BODIPYFL).
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Affiliation(s)
- Rigo Pantoja
- Division of Biology, California Institute of Technology, Pasadena, California 91125, USA
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Rodriguez EA, Lester HA, Dougherty DA. Improved amber and opal suppressor tRNAs for incorporation of unnatural amino acids in vivo. Part 1: minimizing misacylation. RNA (NEW YORK, N.Y.) 2007; 13:1703-14. [PMID: 17698638 PMCID: PMC1986802 DOI: 10.1261/rna.666807] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The incorporation of unnatural amino acids site-specifically is a valuable technique for structure-function studies, incorporation of biophysical probes, and determining protein-protein interactions. THG73 is an amber suppressor tRNA used extensively for the incorporation of >100 different residues in over 20 proteins, but under certain conditions THG73 is aminoacylated in vivo by endogenous aminoacyl-tRNA synthetase. Similar aminoacylation is seen with the Escherichia coli Asn amber suppressor tRNA, which has also been used to incorporate UAAs in many studies. We now find that the natural amino acid placed on THG73 is Gln. Since the E. coli GlnRS recognizes positions in the acceptor stem, we made several acceptor stem mutations in the second to fourth positions on THG73. All mutations reduce aminoacylation in vivo and allow for the selection of highly orthogonal tRNAs. To show the generality of these mutations, we created opal suppressor tRNAs that show less aminoacylation in Xenopus oocytes relative to THG73. We have created a library of Tetrahymena thermophila Gln amber suppressor tRNAs that will be useful for determining optimal suppressor tRNAs for use in other eukaryotic cells.
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Affiliation(s)
- Erik A Rodriguez
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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7
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Watanabe T, Muranaka N, Iijima I, Hohsaka T. Position-specific incorporation of biotinylated non-natural amino acids into a protein in a cell-free translation system. Biochem Biophys Res Commun 2007; 361:794-9. [PMID: 17678619 DOI: 10.1016/j.bbrc.2007.07.099] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Accepted: 07/19/2007] [Indexed: 11/23/2022]
Abstract
Biotinylation is useful for the detection, purification and immobilization of proteins. It is performed by chemical modification, although position-specific and quantitative biotinylation is rarely achieved. We developed a position-specific biotinylation method using biotinylated non-natural amino acids. We showed that biotinylated p-aminophenylalanine derivatives were incorporated into a protein more efficiently than biotinylated lysine derivatives in a cell-free translation system. In addition, the biotinylated p-aminophenylalanines overcame the serious position-dependency observed for biotinylated lysines. The present method will be useful for detection and purification of proteins along with comprehensive exploration of surface-exposed residues and oriented immobilization of proteins.
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Affiliation(s)
- Takayoshi Watanabe
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
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Corona C, Bryant BK, Arterburn JB. Synthesis of a biotin-derived alkyne for pd-catalyzed coupling reactions. Org Lett 2006; 8:1883-6. [PMID: 16623575 PMCID: PMC2523258 DOI: 10.1021/ol060458r] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] An efficient synthesis of a terminal alkyne derived from d-biotin was developed to provide an alternative for carboxyl-based biotinylation. This approach was illustrated by the preparation of alkyne- and alkene-linked phenylalanine derivatives using palladium-catalyzed Sonogashira and Oh methodology. (Strept)avidin binding was observed using soluble and immobilized receptors. These results demonstrate the applicability of carbon-linked biotin derivatives for use in affinity-based purification and bioanalytical applications.
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Affiliation(s)
- Cesear Corona
- New Mexico State University, P.O. Box 30001MSC 3C, Las Cruces, New Mexico 88003, USA
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Abstract
Conventional display libraries are generally limited to the 20 naturally occurring amino acids. Here, we demonstrate that novel unnatural amide-linked oligomers can be constructed and encoded in an attached RNA for the purpose of mRNA display library design. To do this, we translated templates of various lengths in a protein synthesis system modified to promote sense codon suppression. Unnatural residues were escorted to the ribosome as chemically acylated tRNAs added to the translation mixture. Our experiments reveal that unnatural peptide oligomers ("encodamers") consisting of an N-substituted amino acid are readily generated as mRNA-peptide fusions with excellent stepwise efficiency. The N-substituted polyamides have strikingly improved proteolytic stability relative to their naturally encoded counterparts. Overall, our work indicates that the ribosome can be used as a synthesis platform to generate encoded combinatorial chemistry outside the universal genetic code.
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Affiliation(s)
- Adam Frankel
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 147-75, Pasadena, CA 91125, USA
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Yan C, Honavar V, Dobbs D. Identification of interface residues in protease-inhibitor and antigen-antibody complexes: a support vector machine approach. Neural Comput Appl 2004; 13:123-129. [PMID: 20526429 DOI: 10.1007/s00521-004-0414-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In this paper, we describe a machine learning approach for sequence-based prediction of protein-protein interaction sites. A support vector machine (SVM) classifier was trained to predict whether or not a surface residue is an interface residue (i.e., is located in the protein-protein interaction surface), based on the identity of the target residue and its ten sequence neighbors. Separate classifiers were trained on proteins from two categories of complexes, antibody-antigen and protease-inhibitor. The effectiveness of each classifier was evaluated using leave-one-out (jack-knife) cross-validation. Interface and non-interface residues were classified with relatively high sensitivity (82.3% and 78.5%) and specificity (81.0% and 77.6%) for proteins in the antigen-antibody and protease-inhibitor complexes, respectively. The correlation between predicted and actual labels was 0.430 and 0.462, indicating that the method performs substantially better than chance (zero correlation). Combined with recently developed methods for identification of surface residues from sequence information, this offers a promising approach to predict residues involved in protein-protein interactions from sequence information alone.
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Affiliation(s)
- Changhui Yan
- Artificial Intelligence Research Laboratory, Iowa State University, Atanasoff Hall 226, Ames, IA 50011-1040, USA
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Forster AC, Tan Z, Nalam MNL, Lin H, Qu H, Cornish VW, Blacklow SC. Programming peptidomimetic syntheses by translating genetic codes designed de novo. Proc Natl Acad Sci U S A 2003; 100:6353-7. [PMID: 12754376 PMCID: PMC164450 DOI: 10.1073/pnas.1132122100] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2003] [Indexed: 11/18/2022] Open
Abstract
Although the universal genetic code exhibits only minor variations in nature, Francis Crick proposed in 1955 that "the adaptor hypothesis allows one to construct, in theory, codes of bewildering variety." The existing code has been expanded to enable incorporation of a variety of unnatural amino acids at one or two nonadjacent sites within a protein by using nonsense or frameshift suppressor aminoacyl-tRNAs (aa-tRNAs) as adaptors. However, the suppressor strategy is inherently limited by compatibility with only a small subset of codons, by the ways such codons can be combined, and by variation in the efficiency of incorporation. Here, by preventing competing reactions with aa-tRNA synthetases, aa-tRNAs, and release factors during translation and by using nonsuppressor aa-tRNA substrates, we realize a potentially generalizable approach for template-encoded polymer synthesis that unmasks the substantially broader versatility of the core translation apparatus as a catalyst. We show that several adjacent, arbitrarily chosen sense codons can be completely reassigned to various unnatural amino acids according to de novo genetic codes by translating mRNAs into specific peptide analog polymers (peptidomimetics). Unnatural aa-tRNA substrates do not uniformly function as well as natural substrates, revealing important recognition elements for the translation apparatus. Genetic programming of peptidomimetic synthesis should facilitate mechanistic studies of translation and may ultimately enable the directed evolution of small molecules with desirable catalytic or pharmacological properties.
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Affiliation(s)
- Anthony C Forster
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
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Ilegems E, Pick HM, Vogel H. Monitoring mis-acylated tRNA suppression efficiency in mammalian cells via EGFP fluorescence recovery. Nucleic Acids Res 2002; 30:e128. [PMID: 12466560 PMCID: PMC137983 DOI: 10.1093/nar/gnf128] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2002] [Revised: 09/27/2002] [Accepted: 09/27/2002] [Indexed: 11/13/2022] Open
Abstract
A reporter assay was developed to detect and quantify nonsense codon suppression by chemically aminoacylated tRNAs in mammalian cells. It is based on the cellular expression of the enhanced green fluorescent protein (EGFP) as a reporter for the site-specific amino acid incorporation in its sequence using an orthogonal suppressor tRNA derived from Escherichia coli. Suppression of an engineered amber codon at position 64 in the EGFP run-off transcript could be achieved by the incorporation of a leucine via an in vitro aminoacylated suppressor tRNA. Microinjection of defined amounts of mutagenized EGFP mRNA and suppressor tRNA into individual cells allowed us to accurately determine suppression efficiencies by measuring the EGFP fluorescence intensity in individual cells using laser-scanning confocal microscopy. Control experiments showed the absence of natural suppression or aminoacylation of the synthetic tRNA by endogenous aminoacyl-tRNA synthetases. This reporter assay opens the way for the optimization of essential experimental parameters for expanding the scope of the suppressor tRNA technology to different cell types.
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Affiliation(s)
- Erwin Ilegems
- Institute of Biomolecular Sciences, Swiss Federal Institute of Technology, Lausanne CH-1015, Switzerland
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13
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Li S, Millward S, Roberts R. In vitro selection of mRNA display libraries containing an unnatural amino acid. J Am Chem Soc 2002; 124:9972-3. [PMID: 12188645 DOI: 10.1021/ja026789q] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The incorporation of unnatural amino acid into selectable, amplifiable peptide and protein libraries expands the chemical diversity of such libraries, thus considerably facilitating the process of obtaining ligands with improved properties (affinity, specificity, and function), particularly against therapeutically interesting targets. Here, we report that biocytin, a biotin derivative of lysine, can be inserted into an mRNA-protein fusion molecule through amber stop codon suppression. We also demonstrate that templates containing the codon corresponding to the biocytin tRNA (a UAG stop codon) can be enriched by iterative cycles of selection against a streptavidin agarose matrix.
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Affiliation(s)
- Shuwei Li
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena 91125, USA
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Li L, Zhong W, Zacharias N, Gibbs C, Lester HA, Dougherty DA. The tethered agonist approach to mapping ion channel proteins--toward a structural model for the agonist binding site of the nicotinic acetylcholine receptor. CHEMISTRY & BIOLOGY 2001; 8:47-58. [PMID: 11182318 DOI: 10.1016/s1074-5521(00)00055-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The integral membrane proteins of neurons and other excitable cells are generally resistant to high resolution structural tools. Structure-function studies, especially those enhanced by the nonsense suppression methodology for unnatural amino acid incorporation, constitute one of the most powerful probes of ion channels and related structures. The nonsense suppression methodology can also be used to incorporate functional side chains designed to deliver novel structural probes to membrane proteins. In this vein, we sought to generalize a potentially powerful tool - the tethered agonist approach - for mapping the agonist binding site of ligand-gated ion channels. RESULTS Using the in vivo nonsense suppression method for unnatural amino acid incorporation, a series of tethered quaternary ammonium derivatives of tyrosine have been incorporated into the nicotinic acetylcholine receptor. At three sites a constitutively active receptor results, but the pattern of activation as a function of chain length is different. At position alpha149, there is a clear preference for a three-carbon tether, while at position alpha93 tethers of 2-5 carbons are comparably effective. At position gamma55/delta57 all tethers except the shortest one can activate the receptor. Based on these and other data, a model for the receptor binding site can be developed by analogy to the acetylcholine esterase crystal structure. CONCLUSION Through the use of nonsense suppression techniques, the tethered agonist approach has been made into a general tool for probing receptor structures. When applied to the nicotinic receptor, the method places new restrictions on developing models for the agonist binding site.
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Affiliation(s)
- L Li
- Division of Chemistry and Chemical Engineering. California Institute of Technology, Pasadena 91125, USA
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Kiick KL, Tirrell DA. Protein Engineering by In Vivo Incorporation of Non-Natural Amino Acids: Control of Incorporation of Methionine Analogues by Methionyl-tRNA Synthetase. Tetrahedron 2000. [DOI: 10.1016/s0040-4020(00)00833-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Spura A, Riel RU, Freedman ND, Agrawal S, Seto C, Hawrot E. Biotinylation of substituted cysteines in the nicotinic acetylcholine receptor reveals distinct binding modes for alpha-bungarotoxin and erabutoxin a. J Biol Chem 2000; 275:22452-60. [PMID: 10791957 DOI: 10.1074/jbc.m001283200] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although previous results indicate that alpha-subunit residues Trp(187), Val(188), Phe(189), Tyr(190), and Pro(194) of the mouse nicotinic acetylcholine receptor are solvent-accessible and are in a position to contribute to the alpha-bungarotoxin (alpha-Bgtx) binding site (Spura, A., Russin, T. S., Freedman, N. D., Grant, M., McLaughlin, J. T., and Hawrot, E. (1999) Biochemistry 38, 4912-4921), little is known about the accessibility of other residues within this region. By determining second-order rate constants for the reaction of cysteine mutants at alpha184-alpha197 with the thiol-specific biotin derivative (+)-biotinyl-3-maleimidopropionamidyl-3,6-dioxaoctanediamine , we now show that only very subtle differences in reactivity (approximately 10-fold) are detectable, arguing that the entire region is solvent-exposed. Importantly, biotinylation in the presence of saturating concentrations of the long neurotoxin alpha-Bgtx is significantly retarded for positions alphaW187C, alphaF189C, and reduced wild-type receptors (alphaCys(192) and alphaCys(193)), further emphasizing their major contribution to the alpha-Bgtx binding site. Interestingly, although biotinylation of position alphaV188C is not affected by the presence of alpha-Bgtx, erabutoxin a, which is a member of the short neurotoxin family, inhibits biotinylation at position alphaV188C, but not at alphaW187C or alphaF189C. Taken together, these results indicate that short and long neurotoxins establish interactions with distinct amino acids on the nicotinic acetylcholine receptor.
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Affiliation(s)
- A Spura
- Department of Molecular Pharmacology, Division of Biology and Medicine, Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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Affiliation(s)
- Hagan Bayley
- Department of Medical Biochemistry and Genetics, Texas A&M University System Health Science Center, 440 Reynolds Medical Building, College Station, Texas 77843-1114, Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, and Department of Chemistry and Center for Research at the Bio/Nano Interface, University of Florida, Gainesville, Florida 32605-1200
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van Hest JCM, Kiick KL, Tirrell DA. Efficient Incorporation of Unsaturated Methionine Analogues into Proteins in Vivo. J Am Chem Soc 2000. [DOI: 10.1021/ja992749j] [Citation(s) in RCA: 215] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sisido M, Hohsaka T. Extension of Protein Functions by the Incorporation of Nonnatural Amino Acids. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1999. [DOI: 10.1246/bcsj.72.1409] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Winans KA, Bertozzi CR. Inner space exploration: the chemical biologist's guide to the cell. CHEMISTRY & BIOLOGY 1998; 5:R313-5. [PMID: 9862801 DOI: 10.1016/s1074-5521(98)90658-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- K A Winans
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
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