Related ArticlesMapping oxygen accessibility to ribonuclease a using high-resolution NMR relaxation spectroscopy.
Biophys J. 2004 Mar;86(3):1713-25
Authors: Teng CL, Bryant RG
Paramagnetic contributions to nuclear magnetic spin-lattice relaxation rate constant induced by freely diffusing molecular oxygen measured at hundreds of different protein proton sites provide a direct means for characterizing the exploration of the protein by oxygen. This report focuses on regions of ribonuclease A where the rate constant enhancements are either quite large or quite small. We find that there are several regions of enhanced oxygen affinity for the protein both on the surface and in interior pockets where sufficient free volume permits. Oxygen has weak associative interactions with a number of surface crevices that are generally between secondary structural elements of the protein fold. Several regions near the surface have higher than expected accessibility to oxygen indicating that structural fluctuations in the protein provide intermolecular access. Oxygen penetrates part of the hydrophobic interior, but affinity does not correlate simply with hydrophobicity indices. Oxygen is excluded from regions of high interior packing density and a few surface sites where x-ray diffraction data have indicated the presence of specific hydration with high occupancy.
High dimensional and high resolution pulse sequences for backbone resonance assignment of intrinsically disordered proteins
High dimensional and high resolution pulse sequences for backbone resonance assignment of intrinsically disordered proteins
Abstract Four novel 5D (HACA(N)CONH, HNCOCACB, (HACA)CON(CA)CONH, (H)NCO(NCA)CONH), and one 6D ((H)NCO(N)CACONH) NMR pulse sequences are proposed. The new experiments employ non-uniform sampling that enables achieving high resolution in indirectly detected dimensions. The experiments facilitate resonance assignment of intrinsically disordered proteins. The novel pulse sequences were successfully tested using δ subunit (20 kDa) of Bacillus subtilis RNA polymerase...
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02-21-2012 03:40 AM
High-resolution NMR field-cycling device for full-range relaxation and structural studies of biopolymers on a shared commercial instrument
High-resolution NMR field-cycling device for full-range relaxation and structural studies of biopolymers on a shared commercial instrument
Abstract Improvements are described in a shuttling field-cycling device (Redfield in Magn Reson Chem 41:753â??768, 2003), designed to allow widespread access to this useful technique by configuring it as a removable module to a commercial 500 MHz NMR instrument. The main improvements described here, leading to greater versatility, high reliability and simple construction, include: shuttling provided by a linear motor driven by an integrated-control...
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12-31-2011 10:40 AM
In vivo oxygen-17 NMR for imaging brain oxygen metabolism at high field
In vivo oxygen-17 NMR for imaging brain oxygen metabolism at high field
Publication year: 2011
Source: Progress in Nuclear Magnetic Resonance Spectroscopy, In Press, Accepted Manuscript, Available online 23 April 2011</br>
Xiao-Hong, Zhu , Wei, Chen</br>
*Highlights:*? This article reviews the developments of in vivo 17O NMR imaging in brain research. ? In vivo 17O NMR imaging has improved significantly at high/ultrahigh field. ? In vivo 17O NMR can noninvasively image brain oxygen metabolism and perfusion. ? In vivo 17O NMR is useful for mapping the functional change in oxygen...
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04-24-2011 03:42 PM
High resolution NMR spectroscopy of nanocrystalline proteins at ultra-high magnetic field
High resolution NMR spectroscopy of nanocrystalline proteins at ultra-high magnetic field
Abstract Magic-angle spinning (MAS) solid-state NMR (SSNMR) spectroscopy of uniformly-13C,15N labeled protein samples provides insight into atomic-resolution chemistry and structure. Data collection efficiency has advanced remarkably in the last decade; however, the study of larger proteins is still challenged by relatively low resolution in comparison to solution NMR. In this study, we present a systematic analysis of SSNMR protein spectra acquired at 11.7, 17.6 and 21.1 Tesla (1H frequencies of...
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01-09-2011 12:46 PM
[NMR paper] Backbone dynamics of the cytotoxic ribonuclease alpha-sarcin by 15N NMR relaxation me
Backbone dynamics of the cytotoxic ribonuclease alpha-sarcin by 15N NMR relaxation methods.
Related Articles Backbone dynamics of the cytotoxic ribonuclease alpha-sarcin by 15N NMR relaxation methods.
J Biomol NMR. 2002 Dec;24(4):301-16
Authors: Pérez-Cañadillas JM, Guenneugues M, Campos-Olivas R, Santoro J, Martínez del Pozo A, Gavilanes JG, Rico M, Bruix M
The cytotoxic ribonuclease alpha-sarcin is a 150-residue protein that inactivates ribosomes by selectively cleaving a single phosphodiester bond in a strictly conserved rRNA loop. In order...
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11-24-2010 08:58 PM
[NMR paper] A protein folding intermediate of ribonuclease T1 characterized at high resolution by
A protein folding intermediate of ribonuclease T1 characterized at high resolution by 1D and 2D real-time NMR spectroscopy.
Related Articles A protein folding intermediate of ribonuclease T1 characterized at high resolution by 1D and 2D real-time NMR spectroscopy.
J Mol Biol. 1999 Jan 15;285(2):829-42
Authors: Balbach J, Steegborn C, Schindler T, Schmid FX
The rate-limiting step during the refolding of S54G/P55N ribonuclease T1 is determined by the slow trans-->cis prolyl isomerisation of Pro39. We investigated the refolding of this variant by...
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11-18-2010 07:05 PM
[NMR paper] High-resolution NMR of biological solids.
High-resolution NMR of biological solids.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles High-resolution NMR of biological solids.
Curr Opin Struct Biol. 1996 Oct;6(5):624-9
Authors: McDowell LM, Schaefer J
Solid-state NMR experiments have recently provided a number of biochemical insights: motionally averaged 2H lineshapes have shown that the motion of a backbone loop protecting a protein binding site is not ligand gated; isotropic 13C chemical shifts of...
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08-22-2010 02:20 PM
[NMR paper] Thermodynamics of unfolding of ribonuclease A under high pressure. A study by proton
Thermodynamics of unfolding of ribonuclease A under high pressure. A study by proton NMR.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles Thermodynamics of unfolding of ribonuclease A under high pressure. A study by proton NMR.
J Mol Biol. 1995 Jul 28;250(5):689-94
Authors: Yamaguchi T, Yamada H, Akasaka K
Thermodynamic stability of ribonuclease A (6.2 mM pH 1.0, 0.15 M KCl, in 2H2O) has been studied in the pressure range of 1 to 2000 atm and in the temperature range...