Related Articles19F-NMR spin-spin relaxation (T2) method for characterizing volatile anesthetic binding to proteins. Analysis of isoflurane binding to serum albumin.
Biochemistry. 1992 Aug 11;31(31):7069-76
Authors: Dubois BW, Evers AS
This paper characterizes the low-affinity ligand binding interactions of a fluorinated volatile anesthetic, isoflurane (CHF2OCHClCF3), with bovine serum albumin (BSA) using 19F-NMR transverse relaxation (T2). 19F-NMR spectra of isoflurane in aqueous BSA reveal a single isoflurane trifluoromethyl resonance, indicative of rapid exchange of isoflurane between protein-bound and aqueous (free) environments. The exchange is slow enough, however, that the chemical shift difference between bound and free isoflurane (delta omega = 0.545 ppm) contributes to the observed isoflurane T2. The contribution of delta omega to T2 can be minimized by shortening the interval between 180 degrees refocusing pulses in the Carr-Purcell-Meiboom-Gill pulse sequence used to monitor T2. Analysis of the dependence of T2 on interpulse interval additionally allows determination of the T2 (6.2 ms) and the average lifetime (tau b = 187 microseconds) of bound isoflurane molecules. By use of a short interpulse interval (less than 100 microseconds), T2 measurements can readily be used to analyze equilibrium binding of isoflurane to BSA. This analysis revealed a discrete saturable binding component with a KD = 1.4 mM that was eliminated either by coincubation with oleic acid (6 mol/mol of BSA) or by conversion of BSA to its "expanded" form by titration to pH 2.5. The binding was independently characterized using a gas chromatographic partition analysis (KD = 1.4 mM, Bmax = 3-4 sites). In summary, this paper describes a method whereby T2 measurements can be used to characterize equilibrium binding of low-affinity ligands to proteins without the confounding contributions of chemical shift.(ABSTRACT TRUNCATED AT 250 WORDS)
Water proton spin saturation affects measured protein backboneN spin relaxation rates
Water proton spin saturation affects measured protein backboneN spin relaxation rates
Publication year: 2011
Source: Journal of Magnetic Resonance, Available online 1 October 2011</br>
Kang*Chen, Nico*Tjandra</br>
Protein backboneN NMR spin relaxation rates are useful in characterizing the protein dynamics and structures. To observe the protein nuclear-spin resonances a pulse sequence has to include a water suppression scheme. There are two commonly employed methods, saturating or dephasing the water spins with pulse field gradients and keeping them unperturbed with flip-back pulses....
[NMR paper] Investigation of the NMR spin-spin coupling constants across the hydrogen bonds in ub
Investigation of the NMR spin-spin coupling constants across the hydrogen bonds in ubiquitin: the nature of the hydrogen bond as reflected by the coupling mechanism.
Related Articles Investigation of the NMR spin-spin coupling constants across the hydrogen bonds in ubiquitin: the nature of the hydrogen bond as reflected by the coupling mechanism.
J Am Chem Soc. 2004 Apr 28;126(16):5093-107
Authors: Tuttle T, Kraka E, Wu A, Cremer D
The indirect scalar NMR spin-spin coupling constants across the H-bonds of the protein ubiquitin were calculated,...
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[NMR paper] NMR study of volatile anesthetic binding to nicotinic acetylcholine receptors.
NMR study of volatile anesthetic binding to nicotinic acetylcholine receptors.
Related Articles NMR study of volatile anesthetic binding to nicotinic acetylcholine receptors.
Biophys J. 2000 Feb;78(2):746-51
Authors: Xu Y, Seto T, Tang P, Firestone L
New lines of evidence suggest that volatile anesthetics interact specifically with proteins. Direct binding analysis, however, has been largely limited to soluble proteins. In this study, specific interaction was investigated between isoflurane, a clinically important volatile anesthetic, and...
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[NMR paper] Spin-state-selective TPPI: a new method for suppression of heteronuclear coupling con
Spin-state-selective TPPI: a new method for suppression of heteronuclear coupling constants in multidimensional NMR experiments.
Related Articles Spin-state-selective TPPI: a new method for suppression of heteronuclear coupling constants in multidimensional NMR experiments.
J Magn Reson. 1999 Aug;139(2):443-6
Authors: Schulte-Herbrüggen T, Briand J, Meissner A, Sřrensen OW
A novel multidimensional NMR pulse sequence tool, spin-state-selective time-proportional phase incrementation (S(3) TPPI), is introduced. It amounts to application of...
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[NMR paper] Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and
Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
Related Articles Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
J Magn Reson B. 1994 May;104(1):11-25
Authors: Kuwata K, Brooks D, Yang H, Schleich T
The derivation of a generalized relaxation matrix equation for the off-resonance rotating-frame spin-lattice...
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[NMR paper] Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and
Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
Related Articles Relaxation-matrix formalism for rotating-frame spin-lattice proton NMR relaxation and magnetization transfer in the presence of an off-resonance irradiation field.
J Magn Reson B. 1994 May;104(1):11-25
Authors: Kuwata K, Brooks D, Yang H, Schleich T
The derivation of a generalized relaxation matrix equation for the off-resonance rotating-frame spin-lattice...