Consulta: subjectFacets:"Phosphoenolpyruvate carboxykinase"
Registros recuperados: 5
Data/hora: 11/06/2024 05:53:03

La citocinina BAP en el metabolismo primario de hojas senescentes de trigo
Provedor de dados: 32
Autores: González Santos, Rosalinda.
La senescencia foliar es la última fase de desarrollo de las hojas, se caracteriza por una serie de cambios fisiológicos y bioquímicos. El principal propósito de éste proceso es la traslocación de nutrientes especialmente el nitrógeno. Las principales biomoléculas del metabolismo primario se degradan como: los pigmentos fotosintéticos, proteínas y enzimas fotosintéticas. Sin embargo, la aspersión externa de la citocinina BAP y la sobre-expresión de isopentenil fosfotransferasa en las hojas retrasa el catabólismo de estos compuestos y mantiene la actividad fotosintética. El objetivo del presente trabajo fue estudiar el efecto de la aplicación externa de la citocinina 6-bencilaminopurina (BAP) en el metabolismo primario, durante la senescencia natural de la...
Tipo: Tesis
Palavras-chave: Azúcares solubles; Fosfoenolpiruvato carboxicinasa; Fosfoenolpiruvato carboxilasa; Triticum aestivum L; Maestría; Botánica; Soluble sugars; Phosphoenolpyruvate carboxykinase; Phosphoenolpyruvate carboxylase; Triticum aestivum L.
Ano: 2008
URL: http://hdl.handle.net/10521/1628

Hepatic phosphoenolpyruvate carboxykinase gene expression is not repressed by dietary carbohydrates in rainbow trout (Oncorhynchus mykiss)
Provedor de dados: 5
Autores: Panserat, Stéphane; Plagnes Juan, E; Breque, Jeanine; Kaushik, Sadasivam.
Phosphoenolpyruvate carboxykinase (PEPCK) is a rate-limiting enzyme in hepatic gluconeogenesis and therefore plays a central role in glucose homeostasis. The aim of this study was to analyse the nutritional regulation of PEPCK gene expression in rainbow trout (Oncorhynchus mykiss), which are known to use dietary carbohydrates poorly. A full-length hepatic PEPCK cDNA (2637 base pairs with one open reading frame putatively encoding a 635-residue protein) was cloned and found to be highly homologous to mammalian PEPCKs. The presence of a putative peptide signal specific to a mitochondrial-type PEPCK in the deduced amino acid sequence suggests that this PEPCK gene codes for a mitochondrial form, In gluconeogenic tissues such as liver, kidney and intestine,...
Tipo: Text
Palavras-chave: Gluconeogenesis; Nutrition; Metabolism; Glucose; Oncorhynchus mykiss; Rainbow trout; Phosphoenolpyruvate carboxykinase.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-414.pdf

Ecophysiological and metabolic adaptations to sulphide exposure of the oyster Crassostrea gigas
Provedor de dados: 5
Autores: Le Moullac, Gilles; Cheize, Marie; Gastineau, Olivier; Daniel, Jean-yves; Le Coz, Jean-rene; Huvet, Arnaud; Moal, Jeanne; Pouvreau, Stephane; Van Wormhoudt, A; Samain, Jean-francois.
The purpose of this study is to examine the response of the oyster Crassostrea gigas to sulphide at different biological scales. A first experiment was designed to measure for 20 h the clearance (CR) and oxygen consumption (OC) rates of oysters exposed at different concentrations of sulphide (0, 3, 6, 12, 20, and 40 mu M). The second experiment was carried out to evaluate the metabolic adaptations to chronic sulphide exposure for 10 days by measuring PK and PEPCK enzyme activities, succinate and alanine content, the adenylate energy charge (AEC), and the activity of the electron transport system (ETS)in whole oysters at above 20 mu M. PK and PEPCK mRNAs and enzyme activities have been measured in adductor muscle. When exposed to sulphide above 20 mu M, CR...
Tipo: Text
Palavras-chave: ATP; AEC; Electron transport system; Succcinate; Alanine; Phosphoenolpyruvate carboxykinase; Pyruvate kinase; Oxygen consumption; Clearance rate; Crassostrea gigas; Sulphide; Oyster.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3924.pdf

Metabolic adjustments in the oyster Crassostrea gigas according to oxygen level and temperature
Provedor de dados: 5
Autores: Le Moullac, Gilles; Queau, Isabelle; Le Souchu, Pierrick; Pouvreau, Stephane; Moal, Jeanne; Le Coz, Jean-rene; Samain, Jean-francois.
The purpose of this study was to examine the responses of the oyster C. gigas to oxygen levels at subcellular and whole-organism levels. Two experiments were carried out. The first experiment was designed to measure at 15°C, 20°C and 25°C for 20 hours the clearance (CR) and oxygen consumption (OC) rates of oysters exposed at different concentrations of oxygen. The goal of this first part was to estimate the hypoxic threshold for oysters below which their metabolism shifts toward anaerobiosis, by estimating the oxygen critical point (PcO2) at 15, 20 and 25°C. The second experiment was carried out to evaluate the metabolic adaptations to hypoxia for 20 days at three temperatures: 12°C, 15°C and 20°C. The metabolic pathways were characterized by the...
Tipo: Text
Palavras-chave: Succinate; Alanine; Phosphoenolpyruvate carboxykinase; Pyruvate kinase; Temperature; Hypoxia; Oysters.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2693.pdf

The Role of Tyrosine 207 in the Reaction Catalyzed by Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase
Provedor de dados: 48
Autores: Andrade,Cherie; Sepulveda,Carolina; Cardemil,Emilio; Jabalquinto,Ana M.
The functional signifcance of tyrosine 207 of Saccharomyces cerevisiae phosphoenolpyruvate carboxykinase was explored by examining the kinetic properties of the Tyr207Leu mutant. The variant enzyme retained the structural characteristics of the wild-type protein as indicated by circular dichroism, intrinsic fuorescence spectroscopy, and gel-exclusion chromatography. Kinetic analyses of the mutated variant showed a 15-fold increase in Km CO2, a 32fold decrease in Vmax, and a 6-fold decrease in Km for phosphoenolpyruvate. These results suggest that the hydroxyl group of Tyr 207 may polarize CO2 and oxaloacetate, thus facilitating the carboxylation/decarboxylation steps.
Tipo: Journal article
Palavras-chave: Phosphoenolpyruvate carboxykinase; Saccharomyces cerevisiae; CO2 interaction.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000200007