The amino acids 4-(tert-butyl)phenylalanine (Tbf) and 4-(trimethylsilyl)phenylalanine (TMSf), as well as a partially deuterated version of Tbf (dTbf), were chemically synthesized and site-specifically incorporated into different proteins, using an amber stop codon, suppressor tRNA and the broadband aminoacyl-tRNA synthetase originally evolved for the incorporation of p-cyano-phenylalanine. The 1H-NMR signals of the tert-butyl and TMS groups were compared to the 1H-NMR signal of tert-butyltyrosine (Tby) in protein systems with molecular weights ranging from 8 to 54Â*kDa. The 1H-NMR resonance of the TMS group appeared near 0Â*ppm in a spectral region with few protein resonances, facilitating the observation of signal changes in response to ligand binding. In all proteins, the R 2 relaxation rate of the tert-butyl group of Tbf was only little greater than that of Tby (less than two-fold). Deuteration of the phenyl ring of Tbf made only a relatively small difference. The effective T 2 relaxation time of the TMS signal was longer than 140Â*ms even in the 54Â*kDa system.
[NMR paper] Chiral Recognition Studies of ?-(Nonafluoro-tert-butoxy)carboxylic Acids by NMR Spectroscopy.
Chiral Recognition Studies of ?-(Nonafluoro-tert-butoxy)carboxylic Acids by NMR Spectroscopy.
http://www.bionmr.com//www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--pubs.acs.org-images-pubmed-acspubs.jpg Related Articles Chiral Recognition Studies of ?-(Nonafluoro-tert-butoxy)carboxylic Acids by NMR Spectroscopy.
J Org Chem. 2015 Jun 19;80(12):6267-74
Authors: Nemes A, Csóka T, Béni S, Farkas V, Rábai J, Szabó D
Abstract
Three chiral ?-(nonafluoro-tert-butoxy)carboxylic acids (R)-1, (RS)-2, (R)-3 were synthesized to examine...
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[NMR paper] (2S,4R)- and (2S,4S)-perfluoro-tert-butyl 4-hydroxyproline: two conformationally distinct proline amino acids for sensitive application in 19F NMR.
(2S,4R)- and (2S,4S)-perfluoro-tert-butyl 4-hydroxyproline: two conformationally distinct proline amino acids for sensitive application in 19F NMR.
http://www.bionmr.com//www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--pubs.acs.org-images-pubmed-acspubs.jpg Related Articles (2S,4R)- and (2S,4S)-perfluoro-tert-butyl 4-hydroxyproline: two conformationally distinct proline amino acids for sensitive application in 19F NMR.
J Org Chem. 2014 Jun 20;79(12):5880-6
Authors: Tressler CM, Zondlo NJ
Abstract
(2S,4R)- and...
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12-18-2014 11:22 PM
[NMR paper] Photo-CIDNP NMR Spectroscopy of Amino Acids and Proteins.
Photo-CIDNP NMR Spectroscopy of Amino Acids and Proteins.
Related Articles Photo-CIDNP NMR Spectroscopy of Amino Acids and Proteins.
Top Curr Chem. 2013 May 14;
Authors: Kuhn LT
Abstract
Photo-chemically induced dynamic nuclear polarization (CIDNP) is a nuclear magnetic resonance (NMR) phenomenon which, among other things, is exploited to extract information on biomolecular structure via probing solvent-accessibilities of tryptophan (Trp), tyrosine (Tyr), and histidine (His) amino acid side chains both in polypeptides and proteins in...
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05-15-2013 03:12 PM
Generation of Pseudocontact Shifts in Protein NMR Spectra with a Genetically Encoded Cobalt(II)-Binding Amino Acid.
Generation of Pseudocontact Shifts in Protein NMR Spectra with a Genetically Encoded Cobalt(II)-Binding Amino Acid.
Generation of Pseudocontact Shifts in Protein NMR Spectra with a Genetically Encoded Cobalt(II)-Binding Amino Acid.
Angew Chem Int Ed Engl. 2011 Jan 17;50(3):692-4
Authors: Nguyen TH, Ozawa K, Stanton-Cook M, Barrow R, Huber T, Otting G
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Site-specific labeling of proteins with NMR-active unnatural amino acids
Site-specific labeling of proteins with NMR-active unnatural amino acids
Abstract 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...
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01-09-2011 12:46 PM
[NMR paper] Site-selective screening by NMR spectroscopy with labeled amino acid pairs.
Site-selective screening by NMR spectroscopy with labeled amino acid pairs.
Related Articles Site-selective screening by NMR spectroscopy with labeled amino acid pairs.
J Am Chem Soc. 2002 Mar 20;124(11):2446-7
Authors: Weigelt J, van Dongen M, Uppenberg J, Schultz J, Wikström M
A new method for site-selective screening by NMR is presented. The core of the new method is the dual amino acid sequence specific labeling technique. Amino acid X is labeled with (13)C and amino acid Y is labeled with (15)N. Provided only one XY pair occurs in the...
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[NMR paper] Selective 'unlabeling' of amino acids in fractionally 13C labeled proteins: an approa
Selective 'unlabeling' of amino acids in fractionally 13C labeled proteins: an approach for stereospecific NMR assignments of CH3 groups in Val and Leu residues.
Related Articles Selective 'unlabeling' of amino acids in fractionally 13C labeled proteins: an approach for stereospecific NMR assignments of CH3 groups in Val and Leu residues.
J Biomol NMR. 2001 Mar;19(3):267-72
Authors: Atreya HS, Chary KV
A novel methodology for stereospecific NMR assignments of methyl (CH3) groups of Val and Leu residues in fractionally 13C-labeled proteins is...