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| Registros recuperados: 11 | |
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| Gallardo, K.; Firnhaber, C.; Zuber, H.; Héricher, D.; Belghazi, M.; Henry, C.; Küster, H.; Thompson, R.. |
| A comparative study of proteome and transcriptome changes during Medicago truncatula (cultivar Jemalong) seed development has been carried out. Transcript and protein profiles were parallel across the time course for 50% of the comparisons made, but divergent patterns were also observed, indicative of post-transcriptional events. These data, combined with the analysis of transcript and protein distribution in the isolated seed coat, endosperm, and embryo, demonstrated the major contribution made to the embryo by the surrounding tissues. First, a remarkable compartmentalization of enzymes involved in methionine biosynthesis between the seed tissues was revealed that may regulate the availability of sulfur-containing amino acids for embryo protein synthesis... |
| Tipo: Journal Article |
Palavras-chave: SEED DEVELOPMENT; MEDICAGO TRUNCATULA; METHIONINE; METABOLISM; AMINO ACID TRANSPORTERS. |
| Ano: 2007 |
URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD200774127ef2&uri=/notices/prodinra1/2010/09/ |
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| Ferrer, J.L.; Ravanel, S.; Robert, M.; Dumas, R.. |
| Cobalamin-independent methionine synthase (MetE) catalyzes the synthesis of methionine by a direct transfer of the methyl group of N5-methyltetrahydrofolate (CH3-H4PteGlun) to the sulfur atom of homocysteine (Hcy). We report here the first crystal structure of this metalloenzyme under different forms, free or complexed with the Hcy and folate substrates. The Arabidopsis thaliana MetE (AtMetE) crystals reveal a monomeric structure built by two (βα)8 barrels making a deep groove at their interface. The active site is located at the surface of the C-terminal domain, facing the large interdomain cleft. Inside the active site, His647, Cys649, and Cys733 are involved in zinc coordination, whereas Asp605, Ile437, and Ser439 interact with Hcy. Opposite the... |
| Tipo: Journal Article |
Palavras-chave: ARABIDOPSIS THALIANA; STRUCTURE TRIDIMENSIONNELLE; SITE ACTIF; HOMOCYSTEINE; FOLATE; SITE DE LIAISON; ZINC; METHIONINE. |
| Ano: 2004 |
URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PUB0500031912109810&uri=/notices/prodinra1/2010/11/ |
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| Jurjanz, S.; Robert, J.C.; Laurent, F.. |
| Thirty six Holstein cows (26 multiparous, 10 primiparous) were assigned to one of two treatments 17 to 24 days after calving. A basal diet consisting of (DM basis) 61.5 % corn silage, 6.7% wheat straw, 14.9% cracked wheat, 15.6% soybean meal, 1.3 % minerals was fed for 17 weeks as a control diet (treatment 1: T1), or was supplemented with 0.12 % of diet DM with HMBi (treatment 2: T2). The control diet contained an estimated (per kg DM) 1.61 Mcal Net Energy, 100g metabolizable protein (MP), 46g digestible undegraded protein (PDIA from PDI system), 6.91 metabolizable lysine (%MP) and 1.78 metabolizable methionine (%MP). Treatment 2 contained 2.25 metabolizable methionine (%MP), HMBi supplying 0.47 metabolizable methionine (%MP). Results were analysed through... |
| Tipo: Conference Paper |
Palavras-chave: VACHE LAITIERE; RATION; ALIMENTATION COMPLEMENTAIRE; ACIDE AMINE; METHIONINE; PROTEINE DU LAIT; METABOLISME DAIRY COW; MILK PROTEIN; PERFORMANCE; DIET; HMBI. |
| Ano: 2006 |
URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD2007f0cf496e&uri=/notices/prodinra1/2011/03/ |
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| Curien, G.; Ravanel, S.; Robert, M.; Dumas, R.. |
| The Arabidopsis genome contains two genes predicted to code for bifunctional aspartate kinase-homoserine dehydrogenase enzymes (isoforms I and II). These two activities catalyze the first and the third steps toward the synthesis of the essential amino acids threonine, isoleucine, and methionine. We first characterized the kinetic and regulatory properties of the recombinant enzymes, showing that they mainly differ with respect to the inhibition of the homoserine dehydrogenase activity by threonine. A systematic search for other allosteric effectors allowed us to identify an additional inhibitor (leucine) and 5 activators (alanine, cysteine, isoleucine, serine, and valine) equally efficient on aspartate kinase I activity (4-fold activation). The six... |
| Tipo: Journal Article |
Palavras-chave: VOIE METABOLIQUE; ACIDE AMINE ESSENTIEL; ASPARTATE KINASE HOMOSERINE DEHYDROGENASE; ISOFORME; EFFECTEUR ALLOSTERIQUE; INHIBITION ENZYMATIQUE; THREONINE; ISOLEUCINE; METHIONINE; ACTIVITE ENZYMATIQUE. |
| Ano: 2005 |
URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PUB9500032200111312&uri=/notices/prodinra1/2010/11/ |
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| Rulquin, H.. |
| L’objectif de cette étude analytique de la bibliographie a été de préciser les réponses des vaches laitières à un apport post-ruminal de méthionine et de lysine, et d’en déterminer les facteurs de variation. Cent vingt et un essais mesurant les effets de l’apport de ces acides aminés (AA) (sous forme d’infusion dans l’intestin ou d’acides aminés protégés contre les dégradations ruminales) sur la production et la composition du lait ont été utilisés. Globalement, ces AA élèvent la production de protéines en accroissant le taux protéique du lait. L’augmentation est plus importante lorsque les deux AA sont associés (+ 1,1 g/kg) que lorsqu’ils ne le sont pas (+ 0,4 g/kg). Lorsque les deux AA sont apportés ensemble, la réponse est plus importante avec les... |
| Tipo: Journal Article |
Palavras-chave: VACHE LAITIERE; METHIONINE; LYSINE. |
| Ano: 1992 |
URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PUB9200012110024011&uri=/notices/prodinra1/2008/03/ |
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| Rébeillé, F.; Jabrin, S.; Bligny, R.; Loizeau, K.; Gambonnet, B.; Van Wilder, V.; Douce, R.; Ravanel, S.. |
| Despite recent progress in elucidating the regulation of methionine (Met) synthesis, little is known about the catabolism of this amino acid in plants. We present here several lines of evidence indicating that the cleavage of Met catalyzed by Met -lyase is the first step in this process. First, we cloned an Arabidopsis cDNA coding a functional Met -lyase (AtMGL), a cytosolic enzyme catalyzing the conversion of Met into methanethiol, α-ketobutyrate (αKB) and ammonia. AtMGL is present in all the Arabidopsis organs and tissues analyzed, except in quiescent dry mature seeds, thus suggesting that AtMGL is involved in the regulation of Met homeostasis in various situations. Also, we demonstrated that the expression of AtMGL was induced in Arabidopsis cells in... |
| Tipo: Journal Article |
Palavras-chave: PLANTE EXPERIMENTALE; SOUFRE; METHIONINE; RESONANCE MAGNETIQUE NUCLEAIRE; RMN METHIONINE GAMMA LYASE. |
| Ano: 2006 |
URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD2007f25a9ec8&uri=/notices/prodinra1/2008/02/ |
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| Tarrago, L.; Laugier, E.; Zaffagnini, M.; Marchand, C.; Le Maréchal, P.; Rouhier, N.; Lemaire, S.D.; Rey, P.. |
| Methionine oxidation leads to the formation of S- and R-diastereomers of methionine sulfoxide (MetSO), which are reduced back to methionine by methionine sulfoxide reductases (MSRs) A and B, respectively.MSRBs are classified in two groups depending on the conservation of one or two redox-active Cys: 2-Cys MSRBs possess a catalytic Cys reducing MetSO and a resolving Cys allowing regeneration by thioredoxins (Trxs). The second type, 1-Cys MSRBs, possess only the catalytic Cys. The biochemical mechanisms involved in activity regeneration of 1-Cys MSRBs remain largely elusive. In the present work, we used recombinant plastidial Arabidopsis thaliana MSRB1 and MSRB2, as models for 1-Cys and 2-Cys MSRBs, respectively, to delineate the Trx- and... |
| Tipo: Journal Article |
Palavras-chave: ARABIDOPSIS THALIANA; METHIONINE; REGENERATION; ESCHERICHIA-COLI; BIOCHEMICAL-CHARACTERIZATION; S-GLUTATHIONYLATION; CATALYTIC MECHANISM; REDOX REGULATION; REDUCING AGENT; ACTIVE-SITE; PROTEIN; PEROXIREDOXIN; POPLAR. |
| Ano: 2009 |
URL: http://www.prodinra.inra.fr/prodinra/pinra/doc.xsp?id=PROD2010bd5e65f0&uri=/notices/prodinra1/2010/10/ |
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| Registros recuperados: 11 | |
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