ROY Béatrice
Thème de Recherche: Nucléosides & Effecteurs Phosphorylés
beatrice.roy
umontpellier.fr
0448792051
Bureau: N1H09, Etg: 1 - Site : Pôle Chimie Balard Recherche
Domaines de Recherche: - Chimie/Chimie organique
- Sciences du Vivant/Sciences pharmaceutiques
- Sciences du Vivant/Biologie cellulaire
- Sciences du Vivant/Biochimie, Biologie Moléculaire/Biophysique
- Sciences du Vivant/Autre
|
Dernieres productions scientifiques :
|
|
CDP-Ethanolamine and CDP-Choline: one-pot synthesis and 31P NMR study.
Auteur(s): Roy B.
(Article) Publié:
Tetrahedron Letters, vol. 55 p.5306-5310 (2014)
Ref HAL: hal-01061599_v1
DOI: 10.1016/j.tetlet.2014.07.076
Résumé: Herein we report a one-pot multi-step synthesis of the cofactors CDP-Ethanolamine and CDP-Choline starting from cytidine 5′-monophosphate and using commercially available and/or easily prepared reagents. While studying the 31P NMR spectrum of CDP-Ethanolamine, an unexpected characteristic for a pyrophosphate diester was observed as it showed a singlet or two doublets depending upon the pH. Therefore, further NMR studies were undertaken to investigate the pH dependence of the peak splitting pattern and measure the acid dissociation constants of the compounds.
|
|
|
Interaction of human 3-phosphoglycerate kinase with Its two substrates : Is substrate antagonism a kinetic advantage ?
Auteur(s): Lallemand Perrine, Chaloin Laurent, Roy B., Barman Tom, Bowler Matthew W., Lionne Corinne
(Article) Publié:
Journal Of Molecular Biology, vol. 409 p.742-757 (2011)
Ref HAL: hal-00599278_v1
DOI: 10.1016/j.jmb.2011.04.048
Résumé: Substrate antagonism has been described for a variety of enzymes with more than one substrate and is characterized by a lowering of the affinity of one substrate in the presence of the other(s). 3-Phosphoglycerate kinase (PGK) catalyzes phosphotransfer from 1,3-bisphosphoglycerate (bPG) to ADP to give 3-phosphoglycerate (PG) and ATP, and is subject to substrate antagonism. Because of the instability of bPG, antagonism has only been described between PG and ATP or ADP. Here, we show that antagonism also occurs between bPG and ADP. Using the stopped-flow method, we show that the dissociation constant for one substrate increases in the presence of the other, and that this decrease in affinity is mainly due to an increase in the dissociation rate constant. As a consequence, there is an increase in the overall interaction kinetics. Interestingly, in the presence of the mirror image of natural D-ADP, L-ADP (a good substrate for PGK), antagonism is absent. Using rapid-quench-flow, we studied the kinetics of ATP formation. The time courses present the following: (1) a lag with L-ADP, but not with D-ADP, the kinetics of which were similar to the interaction kinetics measured by stopped-flow; (2) a burst that is directed by the phosphotransfer; and (3) a steady-state that is rate limited by the release of product kinetics. Structural explanations for these results are proposed by analyzing the crystallographic structure of the fully closed conformation of PGK in complex with L-ADP, PG, and the transition-state analogue AlF4 − compared to previously determined structures.
|
|
|
Rationally designed aptamer-based fluorescence polarization sensor dedicated to the small target analysis.
Auteur(s): Perrier Sandrine, Ravelet Corinne, Guieu Valérie, Fize Jennifer, Roy B., Perigaud C., Peyrin Eric
(Article) Publié:
Biosensors And Bioelectronics / Biosensors & Bioelectronics, vol. 25 p.1652-1657 (2010)
|
|
|
Multiplexed detection of small analytes by structure-switching aptamer-based capillary electrophoresis.
Auteur(s): Zhu Zhenyu, Ravelet Corinne, Perrier Sandrine, Guieu Valérie, Roy B., Perigaud C., Peyrin Eric
(Article) Publié:
Analytical Chemistry, vol. 82 p.4613-4620 (2010)
|
|
|
Aptamer-Modified Micellar Electrokinetic Chromatography for the Enantioseparation of Nucleotides.
Auteur(s): Ruta J., Perrier Sandrine, Ravelet C., Roy B., Perigaud C., Peyrin E.
(Article) Publié:
Analytical Chemistry, vol. 81 p.1169-1176 (2009)
|
Plus...