Geoffrey Bodenhausen

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Para-water is an analogue of para-hydrogen, where the two proton spins are in a quantum state that is antisymmetric under permutation, also known as singlet state. The populations of the nuclear spin states in para-water are believed to have long lifetimes ...

We analyze the direct excitation of wide one-dimensional spectra of nuclei with spin I = 1/2 or 1 in rotating solids submitted to pulse trains in the manner of Delays Alternating with Nutations for Tailored Excitation (DANTE), either with one short rotor-s ...

As previously demonstrated by Thurber and Tycko, the peak position of Br-79 in potassium bromide (KBr) allows one to determine the temperature of a spinning sample. We propose to adapt the original design by using a compact KBr tablet placed at the bottom ...

Homogeneous line-widths that arise from transverse relaxation tend to be masked by B-0 field inhomogeneity and by multiplets due to homonuclearf-couplings. Besides well-known spin-locking sequences that lead to signals that decay with a rate R-1p without a ...

In solids spinning at the magic angle, the indirect detection of single-quantum (SQ) and double-quantum (DQ) N-14 spectra (l = 1) via spy nuclei S = 1/2 such as protons can be achieved in the manner of heteronuclear single- or multiple-quantum correlation (HSQC or HMQC) spectroscopy. The HMQC method relies on the excitation of two-spin coherences of the type T-11(l) T-11(S) and T-21(l) T-11(S) at the beginning of the evolution interval t(1). The spectra obtained by Fourier transformation from t(1) to omega(

Understanding the molecular determinants underlying protein function requires the characterization of both structure and dynamics at atomic resolution. Nuclear relaxation rates allow a precise characterization of protein dynamics at the Larmor frequencies ...

A review is given of the math. foundations of av. Liouvillian theory and examples are provided of av. Liouvillian expressions derived for sequences in NMR which possess temporal symmetry or antisymmetry. The utility of this approach is demonstrated in the design of pulse sequences to measure the effect of cross-correlation between chem. shift anisotropy and dipolar couplings on relaxation rates in biomols. Exptl. verification of the theory is carried out on a 15N labeled sample of ubiquitin. [on SciFinder (

Owing to its imidazole side chain, histidine participates in various processes such as enzyme catalysis, pH regulation, metal binding, and phosphorylation. The determination of exchange rates of labile protons for such a system is important for understandi ...

A method for heteronuclear decoupling in fast magic-angle spinning NMR measurements comprises application of a decoupling RF-pulse sequence with a decoupling-field amplitude 1⁄2 1 I on spins of a first nucleus and of an excitation pulse on spins of a secon ...

Hyperpolarization by dissolution dynamic nuclear polarization (D-DNP) offers a way of enhancing NMR signals by up to five orders of magnitude in metabolites and other small molecules. Nevertheless, the lifetime of hyperpolarization is inexorably limited, a ...

The conformation of NAD bound to dogfish lactate dehydrogenase (LDH) was reinvestigated by using an NMR expt. that allows one to exploit NOEs to det. internuclear distances between pairs of protons, without perturbation of spin-diffusion effects from other protons belonging either to the cofactor or to the binding pocket of the enzyme. The anal. indicated that the structure of bound NAD was in accord with the conformation detd. in the solid state by x-ray diffraction for the adenosine moiety, but deviated s

This communication describes a three-field experiment where inequivalent scalar coupled spin pairs are hyperpolarized at 3.35 T and 1.2 K by dynamic nuclear polarization (DNP), rapidly transferred to high field (7 T) to prepare a suitable initial condition ...

The modulation of spin echoes by homonuclear scalar couplings render the determination of transverse relaxation rates of individual spins difficult, in particular for molecules that are isotopically enriched in 13C or 15N, and for all molecules with scalar ...

Hyperpolarization of NMR-active nuclei is key to gather high quality spectra of rare species and insensitive isotopes. We have recently established that silica-based materials containing regularly distributed nitroxyl radicals connected to the silica matri ...

A review with 91 refs. The use of solid-state NMR as a tool to det. the structure of membrane mols. is reviewed with a particular emphasis on techniques that provide information on orientation or order. Expts. reported here have been performed in membranes, rather than in micelles or org. solvents. Several ways to prep. and handle the samples are discussed, like sample orientation and magic-angle spinning (MAS). Results concerning lipids, membrane peptides and proteins are included, as well as a discussion

A method is presented for the simultaneous measurement of the spin-lattice (T1) and spin-spin (T2) relaxation times in 13C NMR spectroscopy by means of a simple pulse sequence used in conjunction with 2-dimensional Fourier transformation; the resulting spectra give a direct visual indication of the cases of particular interest where T2 < T1. The primary advantage of this method lies in the simultaneous measurement of both T1 and T2 under nearly identical instrumental conditions, e.g., field inhomogeneity an

Deuterium (H-2) magic-angle spinning (MAS) nuclear magnetic resonance is applied to monitor the dynamics of the exchanging labile deuterons of polycrystalline L-histidine hydrochloride monohydrate-d(7) and -oxalic acid dihydrate-d(6). Direct experimental e ...

A comprehensive description is presented of the effects on two-spin coherences (i.e., superpositions of zero- and double-quantum coherences) of cross-correlation between the fluctuations of two different relaxation mechanisms in NMR (NMR). Dipole-dipole (DD) interactions between four nuclei and chem. shift anisotropy (CSA) of two of these nuclei are considered. Two complementary expts. have been designed for 15N,13C-labeled proteins to quantify the effects of cross-correlation between the 13Ca-1Ha and 15N-1

Cross polarization can provide significant enhancements with respect to direct polarization of low-gamma nuclei such as C-13. Substantial gains in sample throughput (shorter polarization times) can be achieved by exploiting shorter build-up times tau(DNP)( ...

By implementing new NMR methods that were designed to map very slow exchange processes we have investigated and characterized the refolding kinetics of a thermodynamically stable 34mer RNA sequence in dynamic equilibrium. The RNA sequence was designed to u ...

Geoffrey Bodenhausen

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Challenges in preparing, preserving and detecting para-water in bulk: overcoming proton exchange and other hurdles

Broadband excitation in solid-state NMR using interleaved DANTE pulse trains with N pulses per rotor period

A spinning thermometer to monitor microwave heating and glass transitions in dynamic nuclear polarization

Determination of transverse relaxation rates in systems with scalar-coupled spins: The role of antiphase coherences

Line-narrowing in proton-detected nitrogen-14 NMR

Nanosecond Time Scale Motions in Proteins Revealed by High-Resolution NMR Relaxometry

Average Liouvillian theory revisited: cross-correlated relaxation between chemical shift anisotropy and dipolar couplings in the rotating frame in nuclear magnetic resonance

Fast Proton Exchange in Histidine: Measurement of Rate Constants through Indirect Detection by NMR Spectroscopy

Efficient heteronuclear decoupling by quenching rotary resonance in solid-state NMR

Long-Lived States of Magnetically Equivalent Spins Populated by Dissolution-DNP and Revealed by Enzymatic Reactions

The conformation of NAD+ bound to lactate dehydrogenase determined by nuclear magnetic resonance with suppression of spin diffusion

Three-field NMR to preserve hyperpolarized proton magnetization as long-lived states in moderate magnetic fields

Apparent Transverse Relaxation Rates in Systems with Scalar-Coupled Protons

Phenylazide Hybrid-Silica - Polarization Platform for Dynamic Nuclear Polarization at Cryogenic Temperatures

Solid-state NMR for the study of membrane systems: the use of anisotropic interactions

Direct comparison of spin-lattice and spin-spin relaxation in high-resolution NMR

Deuterium MAS NMR Studies of Dynamics on Multiple Timescales: Histidine and Oxalic Acid

Relaxation of Two-Spin Coherence Due to Cross-Correlated Fluctuations of Dipole-Dipole Couplings and Anisotropic Shifts in NMR of 15N,13C-Labeled Biomolecules

Cross Polarization for Dissolution Dynamic Nuclear Polarization Experiments at Readily Accessible Temperatures 1.2 < T < 4.2 K

Kinetics of RNA Refolding in Dynamic Equilibrium by 1H-Detected 15N Exchange NMR Spectroscopy