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This article is from PLoS ONE , volume 9 . Abstract Background: Recent studies have identified Streptococcus pneumoniae serotype 11E and serovariant 11Av among isolates previously typed as 11A by classical serotyping methods. Serotype 11E and serovariant 11Av differ from serotype 11A by having totally or partially inactive wcjE, a gene in cps locus coding for an O-acetyl transferase. Serotype 11E is rare among carriage isolates but common among invasive isolates suggesting that it survives better during invasion. Aim of this work was to investigate the epidemiology of serotype 11A in a pneumococcal collection using a new serotyping approach based on High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance (HR-MAS NMR) spectroscopy to distinguish serotypes 11A and 11E. Methods: A collection of 48 (34 invasive and 14 carriage) S. pneumoniae isolates from Italy, previously identified as serotype 11A by the Quellung reaction, were investigated by wcjE sequencing, HR-MAS NMR spectroscopy and the reference flow cytometric serotyping assay (FCSA) based on monoclonal antibodies. Results: HR-MAS NMR spectra from serotypes 11A and 11E showed different NMR peaks indicating that HR-MAS NMR could be used to distinguish these serotypes, although HR-MAS NMR could not distinguish serotype 11Av from serotype 11E unambiguously. Thirty-eight isolates were confirmed to be serotype 11A, 8 isolates with a mutated wcjE were serotype 11E, 1 isolate belonged to serovariant 11Av, and 1 isolate was a mixed population 11A/11Av. All 11E isolates were identified among invasive isolates. Conclusions: We proved that HR-MAS NMR can be of potential use for pneumococcal serotyping. The detection of serotype 11E among invasive isolates in our collection, supports previous epidemiological studies suggesting that mutations in wcjE can represent a mechanism promoting pneumococcal survival during invasion. The discovery of a spectrum of immunochemical diversity within established serotypes should stimulate efforts to develop new serotyping approaches.

This article is from Frontiers in Chemistry , volume 2 . Abstract The low sensitivity and thus need for large sample volume is one of the major drawbacks of Nuclear Magnetic Resonance (NMR) spectroscopy. This is especially problematic for performing rich metabolic profiling of scarce samples such as whole cells or living organisms. This study evaluates a 1H HR-MAS approach for metabolic profiling of small volumes (250 nl) of whole cells. We have applied an emerging micro-NMR technology, high-resolution magic-angle coil spinning (HR-MACS), to study whole Saccharomyces cervisiae cells. We find that high-resolution high-sensitivity spectra can be obtained with only 19 million cells and, as a demonstration of the metabolic profiling potential, we perform two independent metabolomics studies identifying the significant metabolites associated with osmotic stress and aging.

This article is from Frontiers in Chemistry , volume 2 . Abstract The low sensitivity and thus need for large sample volume is one of the major drawbacks of Nuclear Magnetic Resonance (NMR) spectroscopy. This is especially problematic for performing rich metabolic profiling of scarce samples such as whole cells or living organisms. This study evaluates a 1H HR-MAS approach for metabolic profiling of small volumes (250 nl) of whole cells. We have applied an emerging micro-NMR technology, high-resolution magic-angle coil spinning (HR-MACS), to study whole Saccharomyces cervisiae cells. We find that high-resolution high-sensitivity spectra can be obtained with only 19 million cells and, as a demonstration of the metabolic profiling potential, we perform two independent metabolomics studies identifying the significant metabolites associated with osmotic stress and aging.

An analytical chemistry method is described for measuring the reactivity and permeation of fabrics, films, and other solid materials. Reactivity is measured using nuclear magnetic resonance spectroscopy with a high resolution magic angle spinning (solids) probe. Methods for sample preparation and interpretation of results are described.

An analytical chemistry method is described for measuring the reactivity and permeation of fabrics, films, and other solid materials. Reactivity is measured using nuclear magnetic resonance spectroscopy with a high resolution magic angle spinning (solids) probe. Methods for sample preparation and interpretation of results are described.

An analytical chemistry method is described for measuring the reactivity and permeation of fabrics, films, and other solid materials. Reactivity is measured using nuclear magnetic resonance spectroscopy with a high resolution magic angle spinning (solids) probe. Methods for sample preparation and interpretation of results are described.

Memoryless time evolutions are ubiquitous in nature but often correspond to a resolution-induced approximation, i.e. there are correlations in time whose effects are undetectable. Recent advances in the dynamical control of small quantum systems provide the ideal scenario to probe some of these effects. Here we experimentally demonstrate the precise induction of memory effects on the evolution of a quantum coin (qubit) by correlations engineered in its environment. In particular, we design a collisional model in Nuclear Magnetic Resonance (NMR) and precisely control the strength of the effects by changing the degree of correlation in the environment and its time of interaction with the qubit. We also show how these effects can be hidden by the limited resolution of the measurements performed on the qubit. The experiment reinforces NMR as a test bed for the study of open quantum systems and the simulation of their classical counterparts.

Memoryless time evolutions are ubiquitous in nature but often correspond to a resolution-induced approximation, i.e. there are correlations in time whose effects are undetectable. Recent advances in the dynamical control of small quantum systems provide the ideal scenario to probe some of these effects. Here we experimentally demonstrate the precise induction of memory effects on the evolution of a quantum coin (qubit) by correlations engineered in its environment. In particular, we design a collisional model in Nuclear Magnetic Resonance (NMR) and precisely control the strength of the effects by changing the degree of correlation in the environment and its time of interaction with the qubit. We also show how these effects can be hidden by the limited resolution of the measurements performed on the qubit. The experiment reinforces NMR as a test bed for the study of open quantum systems and the simulation of their classical counterparts.

Solid state high resolution $^{13}C$ NMR has been used to investigate the physical properties of pristine $C_{60}$ after intercalation with molecular oxygen. By studying the dipolar and hyperfine interactions between Curie type paramagnetic oxygen molecules and $^{13}C$ nuclei we have shown that neither chemical bonding nor charge transfer results from the intercalation. The $O_2$ molecules diffuse inside the solid $C_{60}$ and occupy the octahedral sites of the fcc crystal lattice. The presence of oxygen does not affect the fast thermal reorientation of the nearest $C_{60}$ molecules. Using Magic Angle Spinning we were able to separate the dipolar and hyperfine contributions to $^{13}C$ NMR spectra, corresponding to buckyballs adjacent to various numbers of oxygen molecules.

This article is from PLoS ONE , volume 9 . Abstract Background and Purpose: Nuclear magnetic resonance (NMR) spectroscopy has become an important technique for tissue studies. Since tissues are in semisolid-state, their high-resolution (HR) spectra cannot be obtained by conventional NMR spectroscopy. Because of this restriction, extraction and high-resolution magic angle spinning (HR MAS) are widely applied for HR NMR spectra of tissues. However, both of the methods are subject to limitations. In this study, the feasibility of HR 1H NMR spectroscopy based on intermolecular multiple-quantum coherence (iMQC) technique is explored using fish muscle, fish eggs, and a whole fish as examples. Materials and Methods: Intact salmon muscle tissues, intact eggs from shishamo smelt and a whole fish (Siamese algae eater) are studied by using conventional 1D one-pulse sequence, Hadamard-encoded iMQC sequence, and HR MAS. Results: When we use the conventional 1D one-pulse sequence, hardly any useful spectral information can be obtained due to the severe field inhomogeneity. By contrast, HR NMR spectra can be obtained in a short period of time by using the Hadamard-encoded iMQC method without shimming. Most signals from fatty acids and small metabolites can be observed. Compared to HR MAS, the iMQC method is non-invasive, but the resolution and the sensitivity of resulting spectra are not as high as those of HR MAS spectra. Conclusion: Due to the immunity to field inhomogeneity, the iMQC technique can be a proper supplement to HR MAS, and it provides an alternative for the investigation in cases with field distortions and with samples unsuitable for spinning. The acquisition time of the proposed method is greatly reduced by introduction of the Hadamard-encoded technique, in comparison with that of conventional iMQC method.

This article is from PLoS ONE , volume 9 . Abstract Background and Purpose: Nuclear magnetic resonance (NMR) spectroscopy has become an important technique for tissue studies. Since tissues are in semisolid-state, their high-resolution (HR) spectra cannot be obtained by conventional NMR spectroscopy. Because of this restriction, extraction and high-resolution magic angle spinning (HR MAS) are widely applied for HR NMR spectra of tissues. However, both of the methods are subject to limitations. In this study, the feasibility of HR 1H NMR spectroscopy based on intermolecular multiple-quantum coherence (iMQC) technique is explored using fish muscle, fish eggs, and a whole fish as examples. Materials and Methods: Intact salmon muscle tissues, intact eggs from shishamo smelt and a whole fish (Siamese algae eater) are studied by using conventional 1D one-pulse sequence, Hadamard-encoded iMQC sequence, and HR MAS. Results: When we use the conventional 1D one-pulse sequence, hardly any useful spectral information can be obtained due to the severe field inhomogeneity. By contrast, HR NMR spectra can be obtained in a short period of time by using the Hadamard-encoded iMQC method without shimming. Most signals from fatty acids and small metabolites can be observed. Compared to HR MAS, the iMQC method is non-invasive, but the resolution and the sensitivity of resulting spectra are not as high as those of HR MAS spectra. Conclusion: Due to the immunity to field inhomogeneity, the iMQC technique can be a proper supplement to HR MAS, and it provides an alternative for the investigation in cases with field distortions and with samples unsuitable for spinning. The acquisition time of the proposed method is greatly reduced by introduction of the Hadamard-encoded technique, in comparison with that of conventional iMQC method.

This article is from PLoS ONE , volume 9 . Abstract Background and Purpose: Nuclear magnetic resonance (NMR) spectroscopy has become an important technique for tissue studies. Since tissues are in semisolid-state, their high-resolution (HR) spectra cannot be obtained by conventional NMR spectroscopy. Because of this restriction, extraction and high-resolution magic angle spinning (HR MAS) are widely applied for HR NMR spectra of tissues. However, both of the methods are subject to limitations. In this study, the feasibility of HR 1H NMR spectroscopy based on intermolecular multiple-quantum coherence (iMQC) technique is explored using fish muscle, fish eggs, and a whole fish as examples. Materials and Methods: Intact salmon muscle tissues, intact eggs from shishamo smelt and a whole fish (Siamese algae eater) are studied by using conventional 1D one-pulse sequence, Hadamard-encoded iMQC sequence, and HR MAS. Results: When we use the conventional 1D one-pulse sequence, hardly any useful spectral information can be obtained due to the severe field inhomogeneity. By contrast, HR NMR spectra can be obtained in a short period of time by using the Hadamard-encoded iMQC method without shimming. Most signals from fatty acids and small metabolites can be observed. Compared to HR MAS, the iMQC method is non-invasive, but the resolution and the sensitivity of resulting spectra are not as high as those of HR MAS spectra. Conclusion: Due to the immunity to field inhomogeneity, the iMQC technique can be a proper supplement to HR MAS, and it provides an alternative for the investigation in cases with field distortions and with samples unsuitable for spinning. The acquisition time of the proposed method is greatly reduced by introduction of the Hadamard-encoded technique, in comparison with that of conventional iMQC method.

This article is from PLoS ONE , volume 9 . Abstract Background and Purpose: Nuclear magnetic resonance (NMR) spectroscopy has become an important technique for tissue studies. Since tissues are in semisolid-state, their high-resolution (HR) spectra cannot be obtained by conventional NMR spectroscopy. Because of this restriction, extraction and high-resolution magic angle spinning (HR MAS) are widely applied for HR NMR spectra of tissues. However, both of the methods are subject to limitations. In this study, the feasibility of HR 1H NMR spectroscopy based on intermolecular multiple-quantum coherence (iMQC) technique is explored using fish muscle, fish eggs, and a whole fish as examples. Materials and Methods: Intact salmon muscle tissues, intact eggs from shishamo smelt and a whole fish (Siamese algae eater) are studied by using conventional 1D one-pulse sequence, Hadamard-encoded iMQC sequence, and HR MAS. Results: When we use the conventional 1D one-pulse sequence, hardly any useful spectral information can be obtained due to the severe field inhomogeneity. By contrast, HR NMR spectra can be obtained in a short period of time by using the Hadamard-encoded iMQC method without shimming. Most signals from fatty acids and small metabolites can be observed. Compared to HR MAS, the iMQC method is non-invasive, but the resolution and the sensitivity of resulting spectra are not as high as those of HR MAS spectra. Conclusion: Due to the immunity to field inhomogeneity, the iMQC technique can be a proper supplement to HR MAS, and it provides an alternative for the investigation in cases with field distortions and with samples unsuitable for spinning. The acquisition time of the proposed method is greatly reduced by introduction of the Hadamard-encoded technique, in comparison with that of conventional iMQC method.

This article is from PLoS ONE , volume 9 . Abstract Background and Purpose: Nuclear magnetic resonance (NMR) spectroscopy has become an important technique for tissue studies. Since tissues are in semisolid-state, their high-resolution (HR) spectra cannot be obtained by conventional NMR spectroscopy. Because of this restriction, extraction and high-resolution magic angle spinning (HR MAS) are widely applied for HR NMR spectra of tissues. However, both of the methods are subject to limitations. In this study, the feasibility of HR 1H NMR spectroscopy based on intermolecular multiple-quantum coherence (iMQC) technique is explored using fish muscle, fish eggs, and a whole fish as examples. Materials and Methods: Intact salmon muscle tissues, intact eggs from shishamo smelt and a whole fish (Siamese algae eater) are studied by using conventional 1D one-pulse sequence, Hadamard-encoded iMQC sequence, and HR MAS. Results: When we use the conventional 1D one-pulse sequence, hardly any useful spectral information can be obtained due to the severe field inhomogeneity. By contrast, HR NMR spectra can be obtained in a short period of time by using the Hadamard-encoded iMQC method without shimming. Most signals from fatty acids and small metabolites can be observed. Compared to HR MAS, the iMQC method is non-invasive, but the resolution and the sensitivity of resulting spectra are not as high as those of HR MAS spectra. Conclusion: Due to the immunity to field inhomogeneity, the iMQC technique can be a proper supplement to HR MAS, and it provides an alternative for the investigation in cases with field distortions and with samples unsuitable for spinning. The acquisition time of the proposed method is greatly reduced by introduction of the Hadamard-encoded technique, in comparison with that of conventional iMQC method.

This article is from PeerJ , volume 1 . Abstract We analyzed the applicability of high-resolution 2H-HMR spectroscopy for the analysis of microbe metabolism in samples of mitochondrion isolated from rat liver and from aqueous extracts of homogenates of rat liver and other organs and tissues in the presence of high D2O contents. Such analysis is possible due to the fast microbe adaptation to life in the heavy water. It is also shown that some enzymatic processes typical for the intact cells are preserved in the homogenized tissue preparations. The microbial and cellular metabolic processes can be differentiated via the strategic use of cell poisons and antibiotics.

A review of the experimental capabilities presently available for the modification of spin Hamiltonians normally encountered in solids has been presented to illustrate the control the still-developing high-resolution, solid state NMR techniques furnish. Examples have been discussed to furnish insight into how such schemes can be used to control the time developemnt of a nuclear spin system to allow a detailed characterization of both the electronic and molecular-frame structure near a nuclear site. While the examples specifically discussed have been chosen from areas of current activity, they are only examples of present efforts, and future developments in this field will undoubtedly furnish many more such examples since the concepts upon which these techniques are based are quite general, and there exists great flexibility for the development of specific experimental schemes for a given problem. (Author)

A review of the experimental capabilities presently available for the modification of spin Hamiltonians normally encountered in solids has been presented to illustrate the control the still-developing high-resolution, solid state NMR techniques furnish. Examples have been discussed to furnish insight into how such schemes can be used to control the time developemnt of a nuclear spin system to allow a detailed characterization of both the electronic and molecular-frame structure near a nuclear site. While the examples specifically discussed have been chosen from areas of current activity, they are only examples of present efforts, and future developments in this field will undoubtedly furnish many more such examples since the concepts upon which these techniques are based are quite general, and there exists great flexibility for the development of specific experimental schemes for a given problem. (Author)

A review of the experimental capabilities presently available for the modification of spin Hamiltonians normally encountered in solids has been presented to illustrate the control the still-developing high-resolution, solid state NMR techniques furnish. Examples have been discussed to furnish insight into how such schemes can be used to control the time developemnt of a nuclear spin system to allow a detailed characterization of both the electronic and molecular-frame structure near a nuclear site. While the examples specifically discussed have been chosen from areas of current activity, they are only examples of present efforts, and future developments in this field will undoubtedly furnish many more such examples since the concepts upon which these techniques are based are quite general, and there exists great flexibility for the development of specific experimental schemes for a given problem. (Author)

Metabolomic analysis of banana during postharvest senescence by 1H-high resolution-NMR 作者： Yuan, Yunfei 1 Zhao, Yupeng 1,2 Yang, Jiali 1 Jiang, Yueming 1 Lu, Fei 3 Jia, Yongxia 1 Yang, Bao 1 作者单位： 1. Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China 2. College of Light Industry and Food Sciences, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China 3. College of Grain Science and Technology, Shenyang Normal University, Shenyang 110034, China 通讯作者： Yang, Bao Email:[email protected] 提交时间： 2017-06-15 摘要: Banana is a tropical fruit widely accepted by people over the world. Its chemical composition is critical for the organoleptic property and nutritional value. In this work, the metabolites change during postharvest senescence was investigated by using NMR spectroscopy. The 1D and 2D NMR spectroscopic information revealed the primary and secondary metabolites in banana fruit, including organic acids, amino acids, carbohydrates and phenolics. Bananas at five senescence stages showed similar chemical profiles, but the levels of the individual compounds varied to a large extent. The principal metabolites responsible for postharvest senescence of banana were valine, alanine, aspartic acid, choline, acetate, glucose, malic acid, gallic acid and dopamine. At stage V, ethanol was present due to the conversion of glucose. Salsolinol was generated due to the conversion of dopamine. This was a characteristic marker for the postharvest senescence of banana fruit. Banana Metabolite NMR Principal component analysis Senescence 来自： 许秋生 分类： 生物学 >> 植物学 引用： ChinaXiv:201706.00497 (或此版本 ChinaXiv:201706.00497V1 ) doi:10.12074/201706.00497 CSTR:32003.36.ChinaXiv.201706.00497.V1 推荐引用方式： Yuan, Yunfei,Zhao, Yupeng,Yang, Jiali,Jiang, Yueming,Lu, Fei,Jia, Yongxia,Yang, Bao.(2017).Metabolomic analysis of banana during postharvest senescence by 1H-high resolution-NMR.中国科学院科技论文预发布平台.[ChinaXiv:201706.00497] 版本历史 [V1] 2017-06-15 17:51:44 ChinaXiv:201706.00497V1 下载全文