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1.
Hye Kyong Kim Saifullah Saifullah Khan Sergio D. Prat Kricun Sibel Goraler Young Hae Choi Robert Verpoorte 《Phytochemistry》2010,71(7):773-26
The genus Ilex to which mate (Ilex paraguariensis) belongs, consists of more than 500 species. A wide range of metabolites including saponins and phenylpropanoids has been reported from Ilex species. However, despite the previous works on the Ilex metabolites, the metabolic similarities between species which can be used for chemotaxonomy of the species are not clear yet. In this study, nuclear magnetic resonance (NMR) spectroscopy-based metabolomics was applied to the classification of 11 South American Ilex species, namely, Ilex argentina, Ilex brasiliensis, Ilex brevicuspis, Ilex dumosa var. dumosa, I. dumosa var. guaranina, Ilex integerrima, Ilex microdonta, I. paraguariensis var. paraguariensis, Ilex pseudobuxus, Ilex taubertiana, and Ilex theezans. 1H NMR combined with principal component analysis (PCA), partial least square-discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA) showed a clear separation between species and resulted in four groups based on metabolomic similarities. The signal congestion of 1H NMR spectra was overcome by the implementation of two-dimensional (2D)-J-resolved and heteronuclear single quantum coherence (HSQC). From the results obtained by 1D- and 2D-NMR-based metabolomics it was concluded that species included in group A (I. paraguariensis) were metabolically characterized by a higher amount of xanthines, and phenolics including phenylpropanoids and flavonoids; group B (I. dumosa var. dumosa and I. dumosa var. guaranina) with oleanane type saponins; group C (I. brasiliensis, I. integerrima, I. pseudobuxus and I. theezans) with arbutin and dicaffeoylquinic acids, and group D (I. argentina, I. brevicuspis, I. microdonta and I. taubertiana) with the highest level of ursane-type saponins. Clear metabolomic discrimination of Ilex species and varieties in this study makes the chemotaxonomic classification of Ilex species possible. 相似文献
2.
Metabolomics is defined as both the qualitative and quantitative analysis of all metabolites in an organism unraveling correlation
with other OMICs data. Many of the technologies used in metabolomics have method-specific advantages and drawbacks in terms
of diversity of metabolites detected, sensitivity, or resolution. In this paper, the potential of NMR spectrometry applied
to metabolomics is reviewed using examples of Nicotiana tabacum and Catharanthus roseus. 相似文献
3.
Metabolic fingerprinting of wild type and transgenic tobacco plants by 1H NMR and multivariate analysis technique 总被引:10,自引:0,他引:10
The metabolomic analysis of wild type and constitutive salicylic acid producing tobacco plants (CSA tobacco, Nicotiana tabacum 'Samsun' NN) plants overexpressing salicylate biosynthetic genes was carried out by 1H NMR spectrometry and multivariate analysis techniques. The principle component analysis (PCA) of the 1H NMR spectra showed a clear discrimination between those samples by PC1 and PC2. The discrimination of non-inoculated, TMV-virus inoculated, and systemic leaves or veins could also be obtained by PCA analysis. Major peaks in 1H NMR spectra contributing to the discrimination were assigned as those of chlorogenic acid, malic acid, and sugars. This method allows an efficient differentiation between wild type and transgenic plants without any pre-purification steps. 相似文献
4.
Suk Weon Kim Bon Cho Koo Jonghyun Kim Jang Ryol Liu 《Biotechnology and Bioprocess Engineering》2007,12(6):653-661
Whole cell extracts ofArabidopsis cell cultures maintained on various sucrose concentrations (0,3, and 6%) were analyzed by1H NMR spectroscopy to determine the comprehensive metabolic change in these cultures during sucrose starvation. The amount
of sucrose, glucose, and fructose in the cells decreased to almost nothing after 12 h of culture in medium without sucrose.
In contrast, the total free amino acid content of the cells increased as the culture proceeded. Among the free amino acids,
phenylalanine and malic acid increased the most, followed by asparagine and alanine, whereas glutamic acid did not change
significantly. These results are in agreement with previous studies using HPLC.1H NMR spectroscopy enabled measurement of changes in the sugar and free amino acid content of whole cell extracts without
fractionation and complicated sample preparation. These results indicate that comprehensive metabolic changes in the cells
can be determined by a simple, rapid method using whole cell extracts and1H NMR spectroscopy. 相似文献
5.
Anna Rull Maria Vinaixa Miguel Ángel Rodríguez Raúl Beltrán Jesús Brezmes Nicolau Cañellas Xavier Correig Jorge Joven 《Biochimie》2009
Monocyte chemoattractant protein-1 (MCP-1) plays a relevant role in macrophage migration but recent findings suggest an additional role in lipid and glucose metabolism. We report the use of 1H NMR spectroscopy as a useful complementary method to assess the metabolic function of this gene in a comparative strategy. This metabonomic analysis was rapid, simple, quantitative and reproducible, and revealed a suggestive relationship between the expression of the MCP-1 gene and hepatic glucose and taurine concentrations. This approach should be considered in genetically modified mice when a metabolic alteration is suspected, or in routine assessment of metabolic phenotype. 相似文献
6.
Yeast iso-1 cytochrome c is a naturally occurring protein that possesses an unusually reactive Cysl02 that imbues iso-1 with a complicated solution chemistry which includes spontaneous dimerization and poorly characterized redox reactions. For this reason previous studies of this typical member of the c-type cytochromes have been relegated to variant proteins in which the 102 position has been mutated, with most common changes involving serine and threonine. However, we have determined sequential 1H resonance assignments for the wild-type native protein because it is the actual participant in yeast mitochondrial electron transfer processes and because the wild-type native protein should be the fundamental assignment basis. In addition to 1H resonance assignments for 97 of 106 amino acids, we have also provided an extensive database of long-range NOEs. Comparison of these NOEs and a chemical shift index based upon -H resonances has lead to identification of solution secondary structural elements that are consistent with the solid-state crystal structure. Although there is currently no efficient expression system that would facilitate isotope labeling of iso-1 cytochrome c, we tried to assess the usefulness of future heteronuclear experiments by using natural-abundance 1H/13C HMQC experiments to unambiguously assign 35 -C resonances. 相似文献
7.
The metabolomic analysis of Brassica rapa leaves treated with methyl jasmonate was performed using 2-dimensional J-resolved NMR spectroscopy combined with multivariate data analysis. The principal component analysis of the J-resolved NMR spectra showed discrimination between control and methyl jasmonate treated plants by principal components 1 and 2. While the level of glucose, sucrose and amino acids showed a decrease after methyl jasmonate treatment, hydroxycinnamates and glucosinolate were highly increased. Methyl jasmonate treatment resulted in a long-term accumulation of indole glucosinolate and indole-3-acetic acid, lasting up to 14 days after treatment. Malate conjugated hydroxycinnamates also exhibited an increase until 14 days after methyl jasmonate treatment, these compounds might play an important role in plant defence responses mediated by methyl jasmonate. 相似文献
8.
In situ 1H NMR monitoring of metyrapone incubations with resting-cells of two strains of Mycobacterium, Mycobacterium aurum MO1 and Mycobacterium sp. RP1, showed the biotransformation of this compound, and more precisely the carbonyl-reduction of metyrapone into the corresponding alcohol, metyrapol. This reduction produced both enantiomers. The use of inhibitors allowed us to show the multiple enzymatic activities involved in this biotransformation including carbonyl reductase (EC 1.1.1.1.84) from the short-chain dehydrogenase superfamily and aldehyde reductase (EC 1.1.1.2) from the aldo-keto reductase superfamily. 相似文献
9.
Rubria Marlen Martínez-Casares Norberto Manjarrez Alvarez Aida Solís Oba Liliana Hernández Vázquez Alberto López-Luna 《Nucleosides, nucleotides & nucleic acids》2017,36(10):652-665
The separation of the diastereoisomers of the nucleoside derivatives of uridine, inosine and adenosine was performed by HPLC using chiral and no chiral columns, it was observed with the no chiral columns the resolution was good enough to determine diastereoisomeric excess. These methods were compared with 1H NMR, and no significant differences were observed between the three techniques. Diastereoisomeric uridine (3a), inosine (3b) and adenosine (4c) cyanohydrins were resolved by 1H nuclear magnetic resonance (1H NMR), chiral normal phase-high-performance liquid chromatography-diode array detector (NP-HPLC-DAD) and reversed phase (RP-HPLC-DAD); these methods allowed the assesment of the percent diastereoisomeric excess (% de) of the nucleosidic cyanohydrins of 3a (4, 6 and 4), 3b (10, 8 and 6) and 4c (4, 4 and 4). To the best of our knowledge, there are no reports using analytical techniques for the separation of the epimers of 3a, 3b and 4c. 相似文献
10.
The role played by external calcium and calcium channels in the recovery from aglycaemic hypoxia in cortical brain slices from 10-day old rats was investigated by1H and31P NMR. 30 minutes of aglycaemic hypoxia significantly decreased the levels of phosphocreatine (PCr), ATP, lactate and intracellular pH (pHi). After a 30 minute recovery period there was incomplete recovery of PCr and ATP with lactate increasing by 50% with pHi normal. When the aglycemic hypoxia was carried out in media which had no added calcium (≈10 μM) the PCr and ATP recovery was significantly greater. Application of diltiazem or verapamil but not nifedipine significantly improved the recovery from the aglycemic hypoxia. These data suggest that calcium influx through L-type voltagegated calcium channels is involved in the ischemic damage in neonatal brain which manifests itself as a decrease in the energy state and an increase in lactate. Dedication This article is dedicated to our friend and colleague Herman Bachelard. We wish to thank him for his comradeship, advice and support over many years. Our hope for him is a long and fruiful retirement and that he will remain active in the neurosciences for many years, even though the establishment has blown for “full time”. 相似文献
11.
The use of time-dependent restraints in molecular simulation in order to generate a conformational ensemble for molecules
that is in accordance with measured ensemble averages for particular observable quantities is investigated. Using a model
system consisting of liquid butane and the cyclic peptide antamanide the reproduction of particular average 3
J-coupling constant values in a molecular dynamics simulation is analysed. It is shown that the multiple-valuedness and the
sizeable gradients of the Karplus curve relating 3
J-coupling constants measured in NMR experiments to the corresponding torsional-angle values cause severe problems when trying
to restrain a 3
J-coupling constant to a value close to the extrema of the Karplus curve. The introduction of a factor oscillating with time
into the restraining penalty function alleviates this problem and enhances the restrained conformational sampling. 相似文献
12.
Matilde Skogen Chauton Trond Røvik Størseth Geir Johnsen 《Journal of applied phycology》2003,15(6):533-542
Chemical composition of the microalga Thalassiosira pseudonana Hasle & Heimdalwas studied with different proton nuclearmagnetic resonance (1H NMR)techniques, and by comparing NMR spectrafrom extraction samples with a spectrumfrom a sample of whole cells we show thathigh-resolution magic angle spinning (HRMAS) 1H NMR can be used for broadrange analysis of metabolic composition inmicroalgal whole cells. Signals fromimportant metabolites such aspolyunsaturated fatty acids (PUFAs)eicosapentaenoic (EPA) and docosahexaenoic(DHA) acids were seen in a 1H NMRspectrum of lipophilic extract, andpossibly also signals from the carotenoidfucoxanthin. In a spectrum of hydrophilicextract we assigned signals to amino acidssuch as glutamine (Gln) and glutamic acid(Glu), carbohydrate and ATP. These findingswere compared to a spectrum of HR MAS1H NMR analysis of whole cells, whereit was possible to find signals coincidentwith the different metabolites seen inspectra of the extraction samples. Sincethe position of resonance peaks in a NMRspectrum depends on the chemicalsurroundings of each atom at the time ofanalysis some peak shift differencesbetween extract and whole cell samplespectra may occur, but signal shifts werenot significantly different between theanalyses here. In addition, application ofHR MAS highly increased spectral resolutionin the complex whole cell sample. Wetherefore suggest that HR MAS 1H NMRanalysis is a suitable analysis tool tostudy metabolic composition directly onwhole cells of microalgae, making itpossible to study a broad range ofmetabolites simultaneously without tediousextraction procedures. 相似文献
13.
Okada H Fukushi E Onodera S Nishimoto T Kawabata J Kikuchi M Shiomi N 《Carbohydrate research》2003,338(9):879-885
Five novel oligosaccharides (tetra-, penta- and hexa-saccharides) were synthesized by glucosyltransfer from beta-D-glucose 1-phosphate to isokestose (O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-alpha-D-glucopyranoside) or nystose (O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-alpha-D-glucopyranoside) using Thermoanaerobacter brockii kojibiose phosphorylase. The oligosaccharides were identified as 2(2-alpha-D-glucopyranosyl)(m)isokestose; [O-alpha-D-glucopyranosyl-(1-->2)](m)-O-[beta-D-fructofuranosyl-(2-->1)](2)-alpha-D-glucopyranoside: m=1, 2, and 3, and 2(2-alpha-D-glucopyranosyl)(n)nystose; [O-alpha-D-glucopyranosyl-(1-->2)](n)-O-[beta-D-fructofuranosyl-(2-->1)](3)-alpha-D-glucopyranoside: n=1 and 2 using gas liquid chromatography analysis of the methyl derivatives, and MALDI-TOF-MS and NMR measurements of the newly formed oligosaccharides. 1H, 13C NMR signals of each saccharide were assigned using 2D-NMR techniques, including COSY, HSQC, HSQC-TOCSY, HMBC, CH(2)-selected E-HSQC, and CH(2)-selected E-HSQC-TOCSY. 相似文献
14.
Leszek Poppe Rainer Stuike-Prill Bernd Meyer Herman van Halbeek 《Journal of biomolecular NMR》1992,2(2):109-136
Summary We present a comprehensive strategy for detailed characterization of the solution conformations of oligosaccharides by NMR spectroscopy and force-field calculations. Our experimental strategy generates a number of interglycosidic spatial constraints that is sufficiently large to allow us to determine glycosidic linkage conformations with a precision heretofore unachievable. In addition to the commonly used {1H,1H} NOE contacts between aliphatic protons, our constraints are: (a) homonuclear NOEs of hydroxyl protons in H2O to other protons in the oligosaccharide, (b) heteronuclear {1H,13C} NOEs, (c) isotope effects of O1H/O2H hydroxyl groups on13C chemical shifts, and (d) long-range heteronuclear scalar coupling across glycosidic bonds.We have used this approach to study the trisaccharide sialyl-(26)-lactose in aqueous solution. The experimentally determined geometrical constraints were compared to results obtained from force-field calculations based on Metropolis Monte Carlo simulations. The molecule was found to exist in 2 families of conformers. The preferred conformations of the (26)-linkage of the trisaccharide are best described by an equilibrium of 2 conformers with angles at –60° or 180° and of the 3 staggered rotamers of the angle with a predominantgt conformer. Three intramolecular hydrogen bonds, involving the hydroxyl protons on C8 and C7 of the sialic acid residue and on C3 of the reducing-end glucose residue, contribute significantly to the conformational stability of the trisaccharide in aqueous solution.
Supplementary material available from the corresponding author: Table containing values for the dihedral angles , , , , and for bond angles , for the six lowest-energy conformations of sialyl-(26)-lactose (1 page). 相似文献
15.
The effects of the local anesthetics tetracaine, procaine (both charged at pH 6), and benzocaine (uncharged) on phospholipid liposomes have been investigated by 500 MHz 1H NMR Spectroscopy. All the drugs reverse the Pr3+ induced shifts of phospholipid resonances in the same sequence as they are shifted by addition of Pr3+: choline POCH2- > choline-CH2N > choline-N(CH3)3 > glycerol > glycerol > acyl C2 > acyl C3. The drug effects result from incorporation of positive charges (tetracaine and procaine) and from the induction of a conformational change of the phospholipid head group via an action on the lipid glycerol backbone (benzocaine). From titration experiments with tetracaine on liposomes containing Pr3+ inside and outside is derived that the drug passes the bilayer by transverse diffusion. Tetracaine partitions outside/inside at a ratio of 21. Changes in linewidths of the drug resonances when incorporated into the liposomes allow the conclusion that the tetracaine molecule is located in an elongated way between the lipid acyl chains with its nitrogen group near the glycerol backbone. Benzocaine, showing strong effects on the line shapes of the protons on C2 and C3 of the lipid acyl chains is also located near the glycerol backbone, the region with the strongest hydrophobic forces.This work was supported by the Deutsche Forschungsgemeinschaft (SFB 30), Cardiology. 相似文献
16.
《Bioscience, biotechnology, and biochemistry》2013,77(9):2032-2036
Creating a plant-cell suspension culture involves first transferring the callus into liquid media, but there are no objective criteria for selecting the location of the callus to be transferred. In this study, inner and outer cells of Catharanthus roseus with various elicitors in solid-state cultures were differentiated by 1H NMR (nuclear magnetic resonance) spectrometry and principal component analysis (PCA). It was found that the samples of various elicitors and relative locations could be separated in PCA-derived score plots. Especially, there was a clear separation between nontreated samples and those cotreated with silver nitrate and methyl jasmonate. Loading-plot analysis was therefore applied to data obtained from nontreated samples and those cotreated with silver nitrate and methyl jasmonate to determine the separation of major metabolites on score plots. The levels of valine, lactic acid, threonine, alanine, arginine, acetic acid, malic acid, succinic acid, citric acid, asparagine, choline, lactose, fumaric acid, phenylalanine, tryptophan, and formic acid were higher in the inner callus than in the outer callus, whereas 2-oxoglutaric acid, oxalacetic acid, sucrose, and glucose dominated in the outer callus. The results obtained in this study suggest that inner and outer calli can be differentiated by 1H-NMR-based metabolomic analysis. 相似文献
17.
Dry or fully imbibed seeds of western white pine (Pinus monticola Dougl. ex D. Don) were studied using high-resolution magnetic resonance imaging (MRI). Analyses of the dry seed revealed many of the gross anatomical features of seed structure. Furthermore, the non-invasive nature of MRI allowed for a study of the dynamics of water and oil distribution during in situ imbibition of a single seed with time-lapse chemical shift selective MRI. During soaking of the dry seed, water penetrated through the seed coat and megagametophyte. The cotyledons of the embryo (located in the chalazal end of the seed) were the first to show hydration followed by the hypocotyl and later the radicle. After penetrating the seed coat, water in the micropylar end of the seed likely also contributed to further hydration of the embryo; however, the micropyle itself did not appear to be a site for water entry into the seed. A model that describes the kinetics of the earlier stages of imbibition is proposed. Non-viable pine seeds captured with MRI displayed atypical imbibition kinetics and were distinguished by their rapid and uncontrolled water uptake. The potential of MR microimaging for detailed studies of water uptake and distribution during the soaking, moist chilling (stratification), and germination of conifer seeds is discussed.Electronic Supplementary Material Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material. 相似文献
18.
A. M. Legrand M. Litaudon J. N. Genthon R. Bagnis T. Yasumoto 《Journal of applied phycology》1989,1(2):183-188
Ciguatoxin, the principal toxin of ciguatera produced by a toxic dinoflagellate and accumulated through the food chain in the viscera of moray eels, was purified. The probable molecular formula C60H86O19 was obtained for the first time by high resolution mass spectrometry. 1H NMR spectra suggested the presence of a primary hydroxyl group suitable for preparing an antigen necessary to develop an enzyme immunoassay. author for correspondence 相似文献
19.
Misicka Aleksandra Verheyden Patricia M.F. Van Binst Georges 《International journal of peptide research and therapeutics》1998,5(5-6):375-377
Summary The conformationalcis-trans equilibrium around the peptide bond in model tripeptides has been determined by 2D NMR methods (HOHAHA, ROESY). The study
was limited to three different N-substituted amino acids in position 2, namely Pro (proline), Tic (1,2,3,4-tetrahydroisoquinoline-3-carboxylic
acid), and N-MePhe (N-methylphenylalanine). In all cases the amino acid in position 1 was tyrosine and in position 3, phenylalanine. The results
of our studies show that thecis-trans ratio depends mostly on the configuration of the amino acids forming the peptide bond undergoing thecis-trans isomerisation. The amino acid following the sequence (in position 3) does not have much influence on thecis-trans isomerisation, indicating that there is no interaction of the side chains between these amino acids. The model peptides with
the L-Tyr-L-AA-(L-or D-)Phe (where AA is N-substituted amino acid) chiralities give 80–100% more of thecis form in comparison to the corresponding peptides with the D-Tyr-L-AA-(L-or D-)Phe chiralities. These results indicate that
the incorporation of N-substituted amino acids in small peptides with the same chirality as the precedent amino acid involved
in the peptide bound undergoing thecis/trans isomerisation moves the equilibrium to a significant amount of thecis form. 相似文献
20.
T. N. Kolokolova N. M. Sergeev A. Yu. Korol’kov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2008,2(4):418-425
Conditions for registration of urinary 1H NMR spectra have been optimized in order to achieve maximal accuracy of quantitative analysis. Urinary samples from patients with acute pancreatitis have been investigated and spectral data of identified urinary metabolites and results of their quantitative determination are given. Employment of 1H NMR spectra is perspective for the development of new laboratory diagnostic methods. 相似文献