The side chains of tyrosine, tryptophan and histidine are able to produce CIDNP (Chemically Induced Dynamic Nuclear Polarization) signals after laser irradiation in the presence of a suitable radical pair-generating dye. Elicitation of such a response in proteins implies surface accessibility of the respective groups to the light-absorbing dye. In principle, this technique allows the monitoring of the effect of ligand binding to a receptor and of site-directed mutagenesis on conformational aspects of any protein if CIDNP-reactive amino acids are involved. The application of this method in glycosciences can provide insights into the protein-carbohydrate interaction process, as illustrated in this initial model study for several N-acetyl-glucosamine-binding lectins of increasing structural complexity as well as for a wild type bacterial sialidase and its mutants. Experimentally, the shape and intensity of CIDNP signals are determined in the absence and in the presence of specific glycoligands. When the carbohydrate is bound, CIDNP signals of side chain protons of tyrosine, tryptophan or histidine residues can be broadened and of reduced intensity. This is the case for hevein, pseudo-hevein, the four hevein domains-containing lectin wheat germ agglutinin (WGA) and the cloned B-domain of WGA 1 (domB) representing one hevein domain. This response indicates either a spatial protection by the ligand or a ligand-induced positioning of formerly surface-exposed side chains into the protein's interior part, thereby precluding interaction with the photo-activated dye. Some signals of protons from the reactive side chains can even disappear when the lectin-ligand complexes are monitored. The ligand binding, however, can apparently also induce a conformational change in a related lectin that causes the appearance of a new signal, as seen for Urtica dioica agglutinin (UDA) which consists of two hevein domains. Additionally, the three CIDNP-reactive amino acids are used as sensors for the detection of conformational changes caused by pH variations or by deliberate amino acid exchanges, as determined for the isolectins hevein and pseudo-hevein as well as for the cloned small sialidase of Clostridium perfringens and two of its mutants. Therefore, CIDNP has proven to be an excellent tool for protein-carbohydrate binding studies and can be established in glycosciences as a third biophysical method beside X-ray-crystallography and high-resolution multidimensional NMR studies which provides reliable information of certain structural aspects of carbohydrate-binding proteins in solution.
(1)H-Detected (13)C Photo-CIDNP as a Sensitivity Enhancement Tool in Solution NMR.
(1)H-Detected (13)C Photo-CIDNP as a Sensitivity Enhancement Tool in Solution NMR.
(1)H-Detected (13)C Photo-CIDNP as a Sensitivity Enhancement Tool in Solution NMR.
J Am Chem Soc. 2011 May 6;
Authors: Lee JH, Sekhar A, Cavagnero S
NMR is a powerful yet intrinsically insensitive technique. The applicability of NMR to chemical and biological systems would be substantially extended by new approaches going beyond current signal-to-noise capabilities. Here, we exploit the large enhancements arising from (13)C photochemically induced dynamic nuclear...
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1H-Detected 13C Photo-CIDNP as a Sensitivity Enhancement Tool in Solution NMR
1H-Detected 13C Photo-CIDNP as a Sensitivity Enhancement Tool in Solution NMR
Jung Ho Lee, Ashok Sekhar and Silvia Cavagnero
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja111613c/aop/images/medium/ja-2010-11613c_0005.gif
Journal of the American Chemical Society
DOI: 10.1021/ja111613c
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA
http://feeds.feedburner.com/~r/acs/jacsat/~4/nDw3hSNxR80
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05-06-2011 05:57 PM
Solid-state photo-CIDNP effect observed in phototropin LOV1-C57S by (13)C magic-angle spinning NMR spectroscopy.
Solid-state photo-CIDNP effect observed in phototropin LOV1-C57S by (13)C magic-angle spinning NMR spectroscopy.
Solid-state photo-CIDNP effect observed in phototropin LOV1-C57S by (13)C magic-angle spinning NMR spectroscopy.
J Am Chem Soc. 2010 Nov 10;132(44):15542-3
Authors: Thamarath SS, Heberle J, Hore PJ, Kottke T, Matysik J
Until now, the solid-state photo-CIDNP effect, discovered in 1994 by Zysmilich and McDermott, has been observed selectively in photosynthetic systems. Here we present the first observation of this effect in a...
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03-02-2011 11:54 AM
[NMR paper] Photo-CIDNP NMR spectroscopy of a heme-containing protein.
Photo-CIDNP NMR spectroscopy of a heme-containing protein.
Related Articles Photo-CIDNP NMR spectroscopy of a heme-containing protein.
J Magn Reson. 2005 Aug;175(2):330-5
Authors: Day IJ, Wain R, Tozawa K, Smith LJ, Hore PJ
There are relatively few examples of the application of photo-CIDNP NMR spectroscopy to chromophore-containing proteins. The most likely reason for this is that simultaneous absorption of light by the photosensitiser molecule and the protein chromophore reduces the effectiveness of the photochemical reaction that produces...
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12-01-2010 06:56 PM
[NMR paper] Photo-CIDNP NMR methods for studying protein folding.
Photo-CIDNP NMR methods for studying protein folding.
Related Articles Photo-CIDNP NMR methods for studying protein folding.
Methods. 2004 Sep;34(1):75-87
Authors: Mok KH, Hore PJ
Chemically induced dynamic nuclear polarization (CIDNP) is a nuclear magnetic resonance phenomenon that can be used to probe the solvent-accessibility of tryptophan, tyrosine, and histidine residues in proteins by means of laser-induced photochemical reactions, resulting in significant enhancement of NMR signals. CIDNP offers good sensitivity as a surface probe of...
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11-24-2010 10:01 PM
[NMR paper] Rapid sample-mixing technique for transient NMR and photo-CIDNP spectroscopy: applica
Rapid sample-mixing technique for transient NMR and photo-CIDNP spectroscopy: applications to real-time protein folding.
Related Articles Rapid sample-mixing technique for transient NMR and photo-CIDNP spectroscopy: applications to real-time protein folding.
J Am Chem Soc. 2003 Oct 15;125(41):12484-92
Authors: Mok KH, Nagashima T, Day IJ, Jones JA, Jones CJ, Dobson CM, Hore PJ
We describe the development and application of a novel rapid sample-mixing technique for real-time NMR (nuclear magnetic resonance) spectroscopy. The apparatus consists...
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11-24-2010 09:16 PM
[NMR paper] Analysis of protein-carbohydrate interaction at the lower size limit of the protein p
Analysis of protein-carbohydrate interaction at the lower size limit of the protein part (15-mer peptide) by NMR spectroscopy, electrospray ionization mass spectrometry, and molecular modeling.
Related Articles Analysis of protein-carbohydrate interaction at the lower size limit of the protein part (15-mer peptide) by NMR spectroscopy, electrospray ionization mass spectrometry, and molecular modeling.
Biochemistry. 2002 Jul 30;41(30):9707-17
Authors: Siebert HC, Lü SY, Frank M, Kramer J, Wechselberger R, Joosten J, André S, Rittenhouse-Olson K, Roy R, von...
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[NMR paper] Carbohydrate-protein interaction studies by laser photo CIDNP NMR methods.
Carbohydrate-protein interaction studies by laser photo CIDNP NMR methods.
Related Articles Carbohydrate-protein interaction studies by laser photo CIDNP NMR methods.
Glycoconj J. 1997 Jun;14(4):531-4
Authors: Siebert HC, Kaptein R, Beintema JJ, Soedjanaatmadja UM, Wright CS, Rice A, Kleineidam RG, Kruse S, Schauer R, Pouwels PJ, Kamerling JP, Gabius HJ, Vliegenthart JF
The side chains of tyrosine, tryptophan and histidine are able to produce CIDNP (Chemically Induced Dynamic Nuclear Polarization) signals after laser irradiation in the...