• Bulletin of the Korean Chemical Society
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• 제30권6호
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• pp.1257-1261
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• 2009

We present the theoretical and experimental results of $^{31}P$ NMR and low energy CID MS/MS study of $Hg^{2+}$ binding to fenitrothion (FN). The calculated $^{31}P$ NMR chemical shifts order for FN with $Hg^{2+}$ complex is in good agreement with experimental $^{31}P$ NMR chemical shifts order. The experimental and theoretical $^{31}P$ NMR study of organophosphorus pesticide with $Hg^{2+}$ gives to important information for organophosphorus pesticide metal complexes. ESI-MS and low energy CID MS/MS experiments of $Hg^{2+}$-FN complexes combined with accurate mass measurements give insight into the metal localization and allow unambiguous identification of fragments and hydrolysis products.

• 분석과학
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• 제18권2호
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• pp.168-172
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• 2005

A comparison study of XRF and $^{31}P$-NMR method for the analysis of phosphorous in lubricating oil has been described. Pure oil and water were used for the observation of matrices effect variation by different analytical methods. Quantitative analysis was carried out by XRF and $^{31}P$-NMR using real samples. Significant difference is observed from the slopes on the calibration curves by the XRF due to the matrices (water: 124.0, oil: 276.6). While the result obtained from XRF showed a large matrix effect, the slopes obtained from $^{31}P$-NMR results of two different matrices, however, are in good agreement ranged of ${\pm}9%$ (water: 4.9, oil: 5.3).

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.183-185
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• 2011

Adenylate kinase-like activity and phosphotransferase-like activity from $F_1$-ATPase of Escherichia coli was revealed by $^{31}P$ NMR spectroscopy. Incubation of F1-ATPase with ADP in the presence of $Mg^{2+}$ shows the appearance of $^{31}P$ resonances from AMP and Pi, suggesting generation of AMP and ATP by adenylate kinase-like activity and the subsequent hydrolysis to Pi. Incubation of $F_1$-ATPase with ADP in the presence of methanol shows additional peak from methyl phosphate, suggesting phosphotransferase-like activity of $F_1$-ATPase. Both adenylate kinase-like activity and phosphotransferase-like activity has not been reported from $F_1$-ATPase of Escherichia coli. $^{31}P$ NMR could be a valuable tool for the investigation of phosphorous related enzyme.

• Journal of Microbiology
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• 제33권4호
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• pp.328-333
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• 1995

$\^$31/ P-NMR experiment was performed to detect phophonates (Pn) utilization and degradation in the several different C-P lyase mutants of E. coli and in E. aerogenes and the recombinants. The relative peak intensity (RPI) for the standard samples of 0.5 mM methylphosphonate (MPn) and 1.0 mM aminoethylphosphonate in glucose-MOPS medium showed 0.5 : 1.0 ratio. In the case of BW14329 (.DELTA.phnC-P, .delta.phoA), RPI did not change significantly after 24 hrs culturing, which means it nearly could not utilize Pn. In vivo $\^$31/ P-NMR spectrum of E. aerogens (BWKL 16627) during 3 hrs starvation showed two intense peaks at 0-2 ppm and at near-10 ppm which indicate intracellular orthophosphate (Pi) and pyrophosphate (PPi), respectively. Both of them might be released by degradation of inorganic polyphosphate pool. When MPn is supplied to the medium as an unique P source, Pi content in the cell has the constant, but PPi seems to be slightly decreased. Recombinants (BWKL 16954) grew slower than E. aerogenes in the glucose-MOPS media with various P sources. In vivo $\^$31/ P-NMR spectrum of recombinant did not show any intense signal in the cell. Surprisingly, under the cultivation adding with MPn, a few intense peaks in the region of Pi AND phospate monoester were detected.

• 한국자기공명학회논문지
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• 제15권2호
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• pp.104-114
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• 2011

Rapid exchange and hydrolysis of the tubulin-bound guanine nucleotides have been known to govern the dynamics of microtubules. However, the instability and low concentration have made it difficult for the microtubule-bound GTP to be observed directly. In this study, we circumvent these problems by lyophilization and using cross-polarization techniques. $^{31}P$ NMR signals were detected from the tubulin-bound GTP in microtubules for the first time. Analysis of the $^{31}P$ CPMAS NMR spectrum indicates that GTP hydrolysis was delayed by the presence of taxol.

• 한국환경농학회지
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• 제12권2호
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• pp.169-175
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• 1993

유기인계 화합물중 독성이 매우 강한 O-ethyl S-methyl ethylphosphonothioate (1)의 화학적, 대사적 산화생성물들에 대한 $^{31}P-NMR$ 분석에서 주된 산화 생성물인 O-ethyl ethylphosphonic acid (2)의 chemical shift가 MCPBA 반응에서 40.15ppm, MMPP 반응에서 30.98ppm, microsomal oxidation system에서 29.31ppm, 그리고 집파리 생체실험에서 29.10ppm으로 반응조건에 따라 서로 상당히 상이하게 관찰되었다. 이 산화 생성물의 $^{31}P-NMR$ spectrum 상에서의 chemical shift에 대한 용매효과는 deutero-chloroform을 사용했을때 30.70ppm, 극성 용매인 deuterium oxide를 사용했을때 40.15ppm으로 관찰되었으며, pH에 대한 효과는 pH 3, 5.6, 14에서는 30ppm을 전후하여, pH 1의 강산성 조건하에서는 47.91ppm에서 나타났다. 이는 유기산 형태의 생성물 (2)가 ionized form이 형성될수있는 조건하에서는 산소원자의 비공유전자쌍들에 의하여 인원자가 차폐되어 chemical shift가 upfield쪽으로 이동을하고, 반면 비극성과 강산성 조건하에서는 Protonated form으로 존재하여 인(燐)원자에 대한 차폐효과가 줄어들기 때문에 downfield쪽으로 이동하는 것으로 관찰되었다.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.531-535
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• 2011

It was regarded that the $^{31}P$ resonances of inherent nucleotides in $F_1$-ATPase (EF1), as large as 380KDa, could not be observed by $^{31}P$ NMR spectroscopy. However, our $^{31}P$ NMR spectroscopy could differentiate between different nucleotide binding sites on EF1 from Escherichia coli. When EF1 was prepared in the absence of $Mg^{2+}$, EF1 contained only ADP. Multiple $^{31}P$ resonances from $\beta$-phosphates of ADP bound to the EF1 were observed from the enzyme prepared without $Mg^{2+}$, suggesting asymmetry or flexibility amongst nucleotide binding sites. $^{31}P$ resonances from enzyme bound ATP could be observed only from EF1, when the enzyme was prepared in the presence of $Mg^{2+}$. This $Mg^{2+}$ dependent ATP binding was very tight that, once bound, nucleotide could not be removed even after removal of $Mg^{2+}$. $^{31}P$ NMR proved to be a valuable tool for investigating phosphorous related enzymes.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1339-1342
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• 2010

$^{31}P$ NMR and ESI-MS studies of $Cu^{2+}$ binding to Fenitrothion (FN) were performed by experimentally and theoretically. The calculated $^{31}P$ NMR chemical shifts for FN-$Cu^{2+}$ complexes are in good agreement with experimental chemical shifts in order, and the results present an important information for organophosphorus pesticide metal complexes. ESI-MS and low energy CID MS/MS experiments of FN-$Cu^{2+}$ complexes combined with accurate mass measurements give insight into the metal localization and allow unambiguous identification of fragments and hydrolysis products.

• Macromolecular Research
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• 제14권5호
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• pp.504-509
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• 2006

Poly(vinyl phosphate-b-styrene) (PVPP-b-PS) block copolymers were synthesized successfully from poly(vinyl alcohol-b-styrene) (PVA-b-PS) by reaction with phosphorus oxychloride and subsequent hydrolysis. The obtained block copolymers were slightly crosslinked, and were characterized by various analytical techniques. The total phosphorus content and the ratio of the differently bound phosphorus were obtained by both solid-state $^{31}P$ NMR and pH titration, but the results differed slightly. Characterization by energy dispersion X-ray analysis (EDS) or Rutherford back scattering (RBS), on the other hand, determined the total phosphorus contents, but the results were quite different from those by solid-state $^{31}P$ NMR.

• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.90-98
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• 2003

In vivo $^31p$ Nuclear Magnetic Resonance ($^31p$NMR) and metabolic studies were carried out on an acetic acid tolerant mutant, Zymomonas mobilis $ZM4/Ac^R$, and compared to those of the parent strain, Z. mobilis ZM4, to evaluate possible mechanisms of acetic acid resistance. This investigation was initiated to determine whether or not the mutant strain might be used as a suitable recombinant host far ethanol production from lignocellulose hydrolysates containing various inhibitory compounds. $ZM4/Ac^R$ showed multiple resistance to other lignocellulosic toxic compounds such as syringaldehyde, furfural, hydroxymethyl furfural, vanillin, and vanillic acid. The mutant strain was resistant to higher concentrations of ethanol or lower pH in the presence of sodium acetate, compared to ZM4 which showed more additive inhibition. in vivo $^31p$ NMR studies revealed that intracellular acidification and de-energization were two mechanisms by which acetic acid exerted its inhibitory effect. For $ZM4/Ac^R$, the internal pH and the energy status were less affected by sodium acetate compared to the parent strain. This resistance to pH change and de-energization caused by acetic acid is a possible explanation for the development of resistance by this strain.