Heteronuclear NMR studies of cobalt corrinoids. 16. Indirect detection of the nitrogen-15 NMR resonances of the axial 5,6-dimethylbenzimidazole nucleotide and of corrin ring N22 and N23 via the heteronuclear multiple-quantum coherence (HMQC) experiment

1993 ◽  
Vol 32 (21) ◽  
pp. 4487-4488 ◽  
Author(s):  
Kenneth L. Brown ◽  
Daniel R. Evans ◽  
Xiang Zou ◽  
Guo Zhang Wu
Keyword(s):  
Quantum Coherence ◽  
Heteronuclear Nmr ◽  
Indirect Detection ◽  
Multiple Quantum ◽  
Nmr Studies ◽  
Heteronuclear Multiple Quantum Coherence ◽  
Multiple Quantum Coherence

scholarly journals Spatially Selective Heteronuclear Multiple-Quantum Coherence Spectroscopy for Biomolecular NMR Studies

ChemPhysChem ◽  
2014 ◽  
Vol 15 (9) ◽  
pp. 1872-1879 ◽  
Author(s):  
Bharathwaj Sathyamoorthy ◽  
David M. Parish ◽  
Gaetano T. Montelione ◽  
Rong Xiao ◽  
Thomas Szyperski
Keyword(s):  
Quantum Coherence ◽  
Multiple Quantum ◽  
Nmr Studies ◽  
Biomolecular Nmr ◽  
Heteronuclear Multiple Quantum Coherence ◽  
Coherence Spectroscopy ◽  
Multiple Quantum Coherence

NMR studies on Fraser fir Abies fraseri (Pursh) Poir. lignins

Holzforschung ◽  
2005 ◽  
Vol 59 (5) ◽  
pp. 488-496 ◽  
Author(s):  
Mikhail Yu. Balakshin ◽  
Ewellyn A. Capanema ◽  
Barry Goldfarb ◽  
John Frampton ◽  
John F. Kadla
Keyword(s):  
Quantum Coherence ◽  
Lignin Content ◽  
Lower Amount ◽  
Multiple Quantum ◽  
Normal Wood ◽  
Nmr Studies ◽  
Oh Groups ◽  
Fraser Fir ◽  
Heteronuclear Multiple Quantum Coherence ◽  
Balsam Woolly Adelgid

Abstract The composition of mature, juvenile uninfested and juvenile infested Fraser fir wood (Rotholz) and the structures of lignins isolated from these woods were elucidated to verify differences between juvenile and mature wood and the effect of balsam woolly adelgid (BWA) infestation. Milled wood lignin (MWL) isolated from mature, juvenile and Rotholz wood were comprehensively characterized using heteronuclear multiple quantum coherence (HMQC) and quantitative 13C NMR techniques. The Rotholz wood was found to have ∼13% higher lignin content and more than five-fold the amount of galactans than that of the uninfested wood. Rotholz lignin possesses higher amounts of p-hydroxyphenyl units and aliphatic OH groups and a lower amount of alkyl-O-alkyl linkages and dibenzodioxocin moieties. The degree of condensation of the Rotholz lignin was rather similar to that of normal wood. Only small differences in the structure of mature and juvenile wood components were found.

Heteronuclear Multiple-Quantum Coherence NMR Spectroscopy of Im-cytC

1995 ◽  
Vol 28 (4) ◽  
pp. 641-650
Author(s):  
Weiping Shao ◽  
Xiaoling Huang ◽  
Gaohua Liu ◽  
Houming Wu ◽  
Wenxia Tang
Keyword(s):  
Nmr Spectroscopy ◽  
Quantum Coherence ◽  
Multiple Quantum ◽  
Heteronuclear Multiple Quantum Coherence ◽  
Multiple Quantum Coherence

scholarly journals Dependence of in vivo glutamine synthetase activity on ammonia concentration in rat brain studied by 1H - 15N heteronuclear multiple-quantum coherence-transfer NMR

1995 ◽  
Vol 311 (2) ◽  
pp. 681-688 ◽  
Author(s):  
K Kanamori ◽  
B D Ross ◽  
E L Kuo
Keyword(s):  
Quantum Coherence ◽  
Ammonia Concentration ◽  
Multiple Quantum ◽  
Blood Ammonia ◽  
Coherence Transfer ◽  
Heteronuclear Multiple Quantum Coherence ◽  
Glutamine Synthesis ◽  
Gaba Synthesis ◽  
Multiple Quantum Coherence

The dependence of the in vivo rate of glutamine synthesis on the substrate ammonia concentration was studied in rat brain by 1H-15N heteronuclear multiple-quantum coherence-transfer NMR in combination with biochemical techniques. In vivo rates were measured at various steady-state blood and brain ammonia concentrations within the ranges 0.4-0.55 mumol/g and 0.86-0.98 mumol/g respectively, after low-rate intravenous 15NH4+ infusion (isotope chase). The rate of glutamine synthesis at steady state was determined from the change in brain [5-15N]glutamine levels during isotope chase, observed selectively through the amide proton by NMR, and 15N enrichments of brain glutamine and of blood and brain ammonia measured byN gas chromatography-MS. The in vivo rate (v) was 3.3-4.5 mumol/h per g of brain at blood ammonia concentrations (s) of 0.40-0.55 mumol/g. A linear increase of 1/v with 1/s permitted estimation of the in vivo glutamine synthetase (GS) activity at a physiological blood ammonia concentration to be 0.4-2.1 mumol/h per g. The observed ammonia-dependence strongly suggests that, under physiological conditions, in vivo GS activity is kinetically limited by sub-optimal in situ concentrations of ammonia as well as glutamate and ATP. Comparison of the observed in vivo GS activity with the reported in vivo rates of glutaminase and of gamma-aminobutyrate (GABA) synthesis suggests that, under mildly hyperammonaemic conditions, glutamine is synthesized at a sufficiently high rate to serve as a precursor of GABA, but glutaminase-catalysed hydrolysis of glutamine is too slow to be the sole provider of glutamate used for GABA synthesis.

scholarly journals t1-Noise eliminated dipolar heteronuclear multiple-quantum coherence solid-state NMR spectroscopy

2020 ◽  
Vol 22 (36) ◽  
pp. 20815-20828 ◽  
Author(s):  
Amrit Venkatesh ◽  
Xuechen Luan ◽  
Frédéric A. Perras ◽  
Ivan Hung ◽  
Wenyu Huang ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Quantum Correlation ◽  
Quantum Coherence ◽  
Pulse Sequences ◽  
Multiple Quantum ◽  
Heteronuclear Correlation ◽  
Heteronuclear Multiple Quantum Coherence ◽  
Multiple Quantum Coherence ◽  
Nuclear Magnetic Resonance Pulse

t1-Noise eliminated (TONE) heteronuclear multiple quantum correlation (HMQC) solid-state nuclear magnetic resonance pulse sequences improve the sensitivity of 2D 1H{X} heteronuclear correlation experiments with X = 17O, 25Mg, 27Al and 35Cl.

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