New Opportunities in Metabolomics and Biochemical Phenotyping for Plant Systems Biology

Pollution contro

MeRy-B: a web knowledgebase for the storage, visualization, analysis and annotation of plant NMR metabolomic profiles

<p>Abstract</p> <p>Background</p> <p>Improvements in the techniques for metabolomics analyses and growing interest in metabolomic approaches are resulting in the generation of increasing numbers of metabolomic profiles. Platforms are required for profile management, as a function of experimental design, and for metabolite identification, to facilitate the mining of the corresponding data. Various databases have been created, including organism-specific knowledgebases and analytical technique-specific spectral databases. However, there is currently no platform meeting the requirements for both profile management and metabolite identification for nuclear magnetic resonance (NMR) experiments.</p> <p>Description</p> <p>MeRy-B, the first platform for plant ¹H-NMR metabolomic profiles, is designed (<it>i</it>) to provide a knowledgebase of curated plant profiles and metabolites obtained by NMR, together with the corresponding experimental and analytical metadata, (<it>ii</it>) for queries and visualization of the data, (<it>iii</it>) to discriminate between profiles with spectrum visualization tools and statistical analysis, (<it>iv</it>) to facilitate compound identification. It contains lists of plant metabolites and unknown compounds, with information about experimental conditions, the factors studied and metabolite concentrations for several plant species, compiled from more than one thousand annotated NMR profiles for various organs or tissues.</p> <p>Conclusion</p> <p>MeRy-B manages all the data generated by NMR-based plant metabolomics experiments, from description of the biological source to identification of the metabolites and determinations of their concentrations. It is the first database allowing the display and overlay of NMR metabolomic profiles selected through queries on data or metadata. MeRy-B is available from <url>http://www.cbib.u-bordeaux2.fr/MERYB/index.php</url>.</p

(Homo)glutathione Deficiency Impairs Root-knot Nematode Development in Medicago truncatula

Root-knot nematodes (RKN) are obligatory plant parasitic worms that establish and maintain an intimate relationship with their host plants. During a compatible interaction, RKN induce the redifferentiation of root cells into multinucleate and hypertrophied giant cells essential for nematode growth and reproduction. These metabolically active feeding cells constitute the exclusive source of nutrients for the nematode. Detailed analysis of glutathione (GSH) and homoglutathione (hGSH) metabolism demonstrated the importance of these compounds for the success of nematode infection in Medicago truncatula. We reported quantification of GSH and hGSH and gene expression analysis showing that (h)GSH metabolism in neoformed gall organs differs from that in uninfected roots. Depletion of (h)GSH content impaired nematode egg mass formation and modified the sex ratio. In addition, gene expression and metabolomic analyses showed a substantial modification of starch and γ-aminobutyrate metabolism and of malate and glucose content in (h)GSH-depleted galls. Interestingly, these modifications did not occur in (h)GSH-depleted roots. These various results suggest that (h)GSH have a key role in the regulation of giant cell metabolism. The discovery of these specific plant regulatory elements could lead to the development of new pest management strategies against nematodes

Detection of phenolic oxidation products in cider apple juice by HPLC electrospray ionisation ion trap mass spectrometry

International audienc

Stratégie d'étude de produits de l'oxydation de polyphénols par LC/MS (application au jus de pomme)

Dans la littérature, des structures de produits d'oxydation de polyphénols ont été proposées à partir de solutions synthétiques. Dans ce travail, la spectrométrie de masse, couplée à la chromatographie liquide, est utilisée comme un outil sélectif et sensible pour détecter des produits d'oxydation de polyphénols, directement dans des jus de pomme. Les produits rencontrés sont issus de réactions entre polyphénols de même classe ou de classes différentes, générant une grande diversité de structure. Parmi les produits d'oxydation présents dans les jus, des dimères d'oxydation de l'acide caféoylquinique, de type dihydrobenzofuranne et dioxanne, ont été complètement identifiés après leur purification à partir de solutions synthétiques. Pour ces produits, l'acide quinique joue le rôle de discriminant chiral, augmentant potentiellement leur multiplicité. L'influence des paramètres pH et rapport acide caféoylquinique sur o-quinone, sur les quantités formées, a été modélisée.RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF

An LC/MS approach to study oxidation products of polyphenolic cimpounds in cider apple juice

International audienc

Characterisation by liquid chromatography coupled to electrospray ionisation ion trap mass spectrometry of phloroglucinol and 4-methylcatechol oxidation products to study the reactivity of epicatechin in an apple juice model system

International audienc

Développement d'outils informatiques pour le traitement et l'analyse des données en RMN-1H, dans un contexte d'expériences métabolomiques

National audienc

Multiplicity of phenolic oxidation products in apple juices and ciders from synthetic medium to commercial products

International audienc