99 research outputs found
Efecto de la variación genotípica sobre la determinación de la calidad de los productos de alcaparras recolectados en el centro-norte de Marruecos
The caper plant (Capparis spinosa L., Capparaceae) from Morocco is described differently, and shows a very variable morphology. In this work, two provenances of caper plant, spontaneous and cultivated, from the North-Central Morocco, are characterized on the basis of morphological and productive criteria. Quantitative and qualitative parameters reveal significant differences between the two origins. The cultivated provenance corresponds to C. spinosa subsp. spinosa, whereas the spontaneous origin is mainly composed of this subspecies and secondarily C. orientalis. Small capers are abundant in the two origins, but their aesthetic quality is more observed in the cultivated one. Caper berries of spontaneous provenance display a longer peduncle and gynophore and those of cultivated provenance are more numerous and thicker. The spontaneous caper genotypes produce capers and caper berries over a longer period and generate less income for the local population.La alcaparra (Capparis spinosa L., Capparaceae) de Marruecos se describe de manera diferente y presenta una morfología muy variable. En este trabajo se caracterizan dos procedencias de alcaparras, espontáneas y cultivadas, del centro-norte de Marruecos, en base a criterios morfológicos y productivos. Los parámetros cuantitativos y cualitativos revelan diferencias significativas entre los dos orígenes. La procedencia cultivada corresponde a C. spinosa subsp. spinosa, mientras que el origen espontáneo está compuesto principalmente por esta subespecie y secundariamente C. orientalis. Las alcaparras pequeñas son abundantes en los dos orígenes, pero su calidad estética se observa más en el cultivado. Las alcaparras de procedencia espontánea presentan un pedúnculo y un ginóforo más largos y las de procedencia cultivada son más numerosas y más gruesas. Los genotipos de alcaparras espontáneas producen alcaparras y bayas de alcaparras durante un período más largo y generan menos ingresos para la población local
A Unifying Mechanism for Mitochondrial Superoxide Production during Ischemia-Reperfusion Injury.
Ischemia-reperfusion (IR) injury occurs when blood supply to an organ is disrupted--ischemia--and then restored--reperfusion--leading to a burst of reactive oxygen species (ROS) from mitochondria. It has been tacitly assumed that ROS production during IR is a non-specific consequence of oxygen interacting with dysfunctional mitochondria upon reperfusion. Recently, this view has changed, suggesting that ROS production during IR occurs by a defined mechanism. Here we survey the metabolic factors underlying IR injury and propose a unifying mechanism for its causes that makes sense of the huge amount of disparate data in this area and provides testable hypotheses and new directions for therapies.Work in our laboratories is supported by the Medical Research Council (UK) and the British Heart Foundation. E.T.C. is supported by a Human Frontiers Science Program fellowship.This is the author accepted manuscript. The final version is available from Cell Press via http://dx.doi.org/10.1016/j.cmet.2015.12.00
Melliferous Flora And Apiculture In The Pre-Rif Of The Province Of Taza (North Of Morocco)
Para cuantificar los valores de diversidad de plantas en el Pre- Rif de la provincia de Taza (Norte de Marruecos), como un enfoque económico del medio ambiente, investigaciones y encuestas de campo han subrayado valores de la flora melífera local para la apicultura. La flora melífera, cuya población saca beneficio, se compone principalmente de 28 especies y interesa también a los apicultores itinerantes. Se estimó un promedio de 12,1±10,8 apicultores por asentamiento rural o “douar”, de los cuales 66,3% son itinerantes y el 33,7% son sedentarios, y un promedio de 36,3±30,4 colmenas por apicultor. Por otra parte, varios tipos de mieles se producen ocalmente y se consume ampliamente como un alimento saludable. La producción de miel en la colmena depende de la especie forrajera: baja para Origanum spp., Thymus spp. y Arbutus unedo, y alta para Anthyllis cytisoides, Rosmarinus officinalis,AbstractTo quantify the plant diversity values in the Pre-Rif of the province of Taza (North of Morocco), as an environmental economic approach, investigations and field surveys have highlighted values of the local melliferous flora for apiculture. Honey flora, whose population pulls profit, consists mainly of 28 species and interests also itinerant beekeepers. We estimated an average of 12.1±10.8 beekeepers by rural settlement or “douar”, of which 66.3% are itinerant and 33.7% are sedentary, and an average of 36.3±30.4 hives by apiarist. Moreover, several types of honeys are produced locally and consumed extensively as a health food. The hive yield in honey is depending on the foraged species: low for Origanum spp., Thymus spp. and Arbutus unedo, and high for Anthyllis cytisoides, Rosmarinus officinalis, Ceratonia siliqua and Ziziphus lotus. The direct benefits of honey flora are assessed to 14,859 MAD.beekeeper-1.year-1.Para cuantificar los valores de diversidad de plantas en el Pre- Rif de la provincia de Taza (Norte de Marruecos), como un enfoque económico del medio ambiente, investigaciones y encuestas de campo han subrayado valores de la flora melífera local para la apicultura. La flora melífera, cuya población saca beneficio, se compone principalmente de 28 especies y interesa también a los apicultores itinerantes. Se estimó un promedio de 12,1±10,8 apicultores por asentamiento rural o “douar”, de los cuales 66,3% son itinerantes y el 33,7% son sedentarios, y un promedio de 36,3±30,4 colmenas por apicultor. Por otra parte, varios tipos de mieles se producen ocalmente y se consume ampliamente como un alimento saludable. La producción de miel en la colmena depende de la especie forrajera: baja para Origanum spp., Thymus spp. y Arbutus unedo, y alta para Anthyllis cytisoides, Rosmarinus officinalis,AbstractTo quantify the plant diversity values in the Pre-Rif of the province of Taza (North of Morocco), as an environmental economic approach, investigations and field surveys have highlighted values of the local melliferous flora for apiculture. Honey flora, whose population pulls profit, consists mainly of 28 species and interests also itinerant beekeepers. We estimated an average of 12.1±10.8 beekeepers by rural settlement or “douar”, of which 66.3% are itinerant and 33.7% are sedentary, and an average of 36.3±30.4 hives by apiarist. Moreover, several types of honeys are produced locally and consumed extensively as a health food. The hive yield in honey is depending on the foraged species: low for Origanum spp., Thymus spp. and Arbutus unedo, and high for Anthyllis cytisoides, Rosmarinus officinalis, Ceratonia siliqua and Ziziphus lotus. The direct benefits of honey flora are assessed to 14,859 MAD.beekeeper-1.year-1
H2S biosynthesis and catabolism: new insights from molecular studies
Hydrogen sulfide (H2S) has profound biological effects within living organisms and is now increasingly being considered alongside other gaseous signalling molecules, such as nitric oxide (NO) and carbon monoxide (CO). Conventional use of pharmacological and molecular approaches has spawned a rapidly growing research field that has identified H2S as playing a functional role in cell-signalling and post-translational modifications. Recently, a number of laboratories have reported the use of siRNA methodologies and genetic mouse models to mimic the loss of function of genes involved in the biosynthesis and degradation of H2S within tissues. Studies utilising these systems are revealing new insights into the biology of H2S within the cardiovascular system, inflammatory disease, and in cell signalling. In light of this work, the current review will describe recent advances in H2S research made possible by the use of molecular approaches and genetic mouse models with perturbed capacities to generate or detoxify physiological levels of H2S gas within tissue
The Hepatic Compensatory Response to Elevated Systemic Sulfide Promotes Diabetes
Impaired hepatic glucose and lipid metabolism are hallmarks of type 2 diabetes. Increased sulfide production or sulfide donor compounds may beneficially regulate hepatic metabolism. Disposal of sulfide through the sulfide oxidation pathway (SOP) is critical for maintaining sulfide within a safe physiological range. We show that mice lacking the liver- enriched mitochondrial SOP enzyme thiosulfate sulfurtransferase (Tst−/− mice) exhibit high circulating sulfide, increased gluconeogenesis, hypertriglyceridemia, and fatty liver. Unexpectedly, hepatic sulfide levels are normal in Tst−/− mice because of exaggerated induction of sulfide disposal, with associated suppression of global protein persulfidation and nuclear respiratory factor 2 target protein levels. Hepatic proteomic and persulfidomic profiles converge on gluconeogenesis and lipid metabolism, revealing a selective deficit in medium-chain fatty acid oxidation in Tst−/− mice. We reveal a critical role of TST in hepatic metabolism that has implications for sulfide donor strategies in the context of metabolic disease
Cysteine and hydrogen sulfide in the regulation of metabolism:Insights from genetics and pharmacology
Obesity and diabetes represent a significant and escalating worldwide health burden. These conditions are characterized by abnormal nutrient homeostasis. One such perturbation is altered metabolism of the sulphur‐containing amino acid cysteine. Obesity is associated with elevated plasma cysteine, whereas diabetes is associated with reduced cysteine levels. One mechanism by which cysteine may act is through its enzymatic breakdown to produce hydrogen sulphide (H(2)S), a gasotransmitter that regulates glucose and lipid homeostasis. Here we review evidence from both pharmacological studies and transgenic models suggesting that cysteine and hydrogen sulphide play a role in the metabolic dysregulation underpinning obesity and diabetes. We then outline the growing evidence that regulation of hydrogen sulphide levels through its catabolism can impact metabolic health. By integrating hydrogen sulphide production and breakdown pathways, we re‐assess current hypothetical models of cysteine and hydrogen sulphide metabolism, offering new insight into their roles in the pathogenesis of obesity and diabetes. © 2015 The Authors. Pathological Society of Great Britain and Ireland
La free R Méthionine sulfoxyde réductase (fRMsr) de Neisseria meningitidis : Mécanisme, catalyse et spécificité structurale
Accès restreint aux membres de l'Université de Lorraine jusqu'au 2016-06-01Methionine sulfoxide reductases (Msr) catalyze the specific reduction of methionine sulfoxides (Met-O) into methionine (Met). They are involved in cell defences against oxidative stress and virulence of pathogenic bacteria of Neisseria genius. This family of enzymes consists of three classes, MsrA and MsrB, structurally-unrelated, Specific for the S and the R epimer of the sulfoxide function of the substrate, respectively. A third class, recently discovered and called fRMsr, selectively reduce the free form of the R epimer of the sulfoxide function. The fRMsr belongs to the family of GAF domains, they are usually involved in cell signaling, and fRMsr represent the first GAF domain to show enzymatic activity. The studies of the Neisseria meningitidis fRMsr have shown that: 1) The Neisseria meningitidis fRMsr have a identical catalytic mechanism to MsrA and MsrB with the formation of at least one intramolecular disulfide bond, Cys84-Cys118 reduced by thioredoxin (Trx) ; 2) The Cys118 is demonstrated to be the catalytic Cys on which a sulfenic acid is formed ; 3) The Reductase step is the rate determining step of the mechanism leading to the formation of the disulfide bond Cys84-Cys118. The combination of the biochemical and kinetics data, and the examination of the 3D structure of the N. meningitidis fRMsr in complex with its substrate shown: 1) an oxyanion hole involved in the accommodation of the carboxylate group ; 2) the carboxylate group of the Asp143 residue involved in the catalysis of step reductase, and 3) The Glu125 residue involved in the recognition and/or positioning of the Met-O probably by the stabilization of the NH3+; 4) the Asp141 residue involved in the positioning of Asp143 and Glu125 residues ; 5) the indole ring of the Trp62 residue involved in stabilizing of the epsilon-methyl groupLes Méthionine sulfoxyde réductases (Msr) catalysent la réduction spécifique des méthionine sulfoxydes (Met-O) en méthionines (Met). Elles sont impliquées dans la résistance des cellules à un stress oxydant et dans la virulence des bactéries pathogènes du genre Neisseria. Cette famille d'enzyme se compose de trois classes, les MsrA et B, structuralement distinctes, et présentant une stéréosléctivité respectivement pour l'isomère S et R de la fonction sulfoxyde du substrat. Une troisième classe, découverte récemment, et appelée fRMsr, catalyse la réduction spécifique de la forme libre de l'isomère R de la fonction sulfoxyde. La fRMsr appartient à la famille des domaines GAF, généralement impliqués dans la signalisation cellulaire, et les fRMsr représentent le premier domaine GAF présentant une activité enzymatique. Les études réalisées au cours de ma thèse sur la fRMsr de Neisseria meningitidis ont permis de montrer que : 1) fRMsr de N. meningitidis présente un mécanisme catalytique identique à MsrA/B avec la formation d'au moins un pont disulfure intramoléculaire Cys84-Cys118 réduit par la thiorédoxine (Trx) ; 2) La Cys118 est le résidu catalytique sur lequel l'intermédiaire acide sulfénique doit se former ; 3) L'étape réductase est l'étape cinétiquement déterminante du mécanisme à deux étapes conduisant à la formation du pont disulfure Cys84-Cys118. La combinaison de l'analyse des résultats cinétiques, et de la structure tridimensionnelle de la fRMsr de N. meningitidis en complexe avec le substrat ont permis de montrer : 1) L'existence d'un site de reconnaissance oxyanion impliqué dans la stabilisation de la fonction carboxylate ; 2) Un rôle de la fonction carboxylate du résidu Asp143 dans la catalyse de l'étape réductase ; 3) Le résidu Glu125 est impliqué dans la reconnaissance et/ou le positionnement du substrat Met-O probablement via la stabilisation du groupement NH3+ ; 4) Un rôle du résidu Asp141 dans le positionnement des résidus Asp143 et Glu125 ; 5) le noyau indole du Trp62 est impliqué dans la stabilisation du groupe méthyle-[epsilon
The Free R Methionine sulfoxide reductase (fRMsr) from Neisseria meningitidis : Mecanism, catalysis and specificity
Les Méthionine sulfoxyde réductases (Msr) catalysent la réduction spécifique des méthionine sulfoxydes (Met-O) en méthionines (Met). Elles sont impliquées dans la résistance des cellules à un stress oxydant et dans la virulence des bactéries pathogènes du genre Neisseria. Cette famille d'enzyme se compose de trois classes, les MsrA et B, structuralement distinctes, et présentant une stéréosléctivité respectivement pour l'isomère S et R de la fonction sulfoxyde du substrat. Une troisième classe, découverte récemment, et appelée fRMsr, catalyse la réduction spécifique de la forme libre de l'isomère R de la fonction sulfoxyde. La fRMsr appartient à la famille des domaines GAF, généralement impliqués dans la signalisation cellulaire, et les fRMsr représentent le premier domaine GAF présentant une activité enzymatique. Les études réalisées au cours de ma thèse sur la fRMsr de Neisseria meningitidis ont permis de montrer que : 1) fRMsr de N. meningitidis présente un mécanisme catalytique identique à MsrA/B avec la formation d'au moins un pont disulfure intramoléculaire Cys84-Cys118 réduit par la thiorédoxine (Trx) ; 2) La Cys118 est le résidu catalytique sur lequel l'intermédiaire acide sulfénique doit se former ; 3) L'étape réductase est l'étape cinétiquement déterminante du mécanisme à deux étapes conduisant à la formation du pont disulfure Cys84-Cys118. La combinaison de l'analyse des résultats cinétiques, et de la structure tridimensionnelle de la fRMsr de N. meningitidis en complexe avec le substrat ont permis de montrer : 1) L'existence d'un site de reconnaissance oxyanion impliqué dans la stabilisation de la fonction carboxylate ; 2) Un rôle de la fonction carboxylate du résidu Asp143 dans la catalyse de l'étape réductase ; 3) Le résidu Glu125 est impliqué dans la reconnaissance et/ou le positionnement du substrat Met-O probablement via la stabilisation du groupement NH3+ ; 4) Un rôle du résidu Asp141 dans le positionnement des résidus Asp143 et Glu125 ; 5) le noyau indole du Trp62 est impliqué dans la stabilisation du groupe méthyle-[epsilon]Methionine sulfoxide reductases (Msr) catalyze the specific reduction of methionine sulfoxides (Met-O) into methionine (Met). They are involved in cell defences against oxidative stress and virulence of pathogenic bacteria of Neisseria genius. This family of enzymes consists of three classes, MsrA and MsrB, structurally-unrelated, Specific for the S and the R epimer of the sulfoxide function of the substrate, respectively. A third class, recently discovered and called fRMsr, selectively reduce the free form of the R epimer of the sulfoxide function. The fRMsr belongs to the family of GAF domains, they are usually involved in cell signaling, and fRMsr represent the first GAF domain to show enzymatic activity. The studies of the Neisseria meningitidis fRMsr have shown that: 1) The Neisseria meningitidis fRMsr have a identical catalytic mechanism to MsrA and MsrB with the formation of at least one intramolecular disulfide bond, Cys84-Cys118 reduced by thioredoxin (Trx) ; 2) The Cys118 is demonstrated to be the catalytic Cys on which a sulfenic acid is formed ; 3) The Reductase step is the rate determining step of the mechanism leading to the formation of the disulfide bond Cys84-Cys118. The combination of the biochemical and kinetics data, and the examination of the 3D structure of the N. meningitidis fRMsr in complex with its substrate shown: 1) an oxyanion hole involved in the accommodation of the carboxylate group ; 2) the carboxylate group of the Asp143 residue involved in the catalysis of step reductase, and 3) The Glu125 residue involved in the recognition and/or positioning of the Met-O probably by the stabilization of the NH3+; 4) the Asp141 residue involved in the positioning of Asp143 and Glu125 residues ; 5) the indole ring of the Trp62 residue involved in stabilizing of the epsilon-methyl grou
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