Search results for "ADP"

A Deficiency in Respiratory Complex I in Heart Mitochondria from Vitamin A-Deficient Rats Is Counteracted by an Increase in Coenzyme Q

1997

Defects of NADH:coenzyme Q oxidoreductase (complex I) of mitochondria have been described in many congenital and acquired diseases. Administration of coenzyme Q (CoQ, ubiquinone) has been shown to benefit patients with some of these diseases. However, the mechanisms by which CoQ exerts the therapeutic effects are not clearly understood. A reason could be the lack of saturation of CoQ, in kinetic terms, for complex I activity. However, this hypothesis has not been proved in vivo because of the difficulty to incorporate CoQ into the mitochondrial membranes. We have found a deficiency in respiratory complex I in heart mitochondria from vitamin A-deficient rats which was accompanied by high CoQ…

NAD(P)H regeneration is the key for heterolactic fermentation of hexoses in Oenococcus oeni

2002

Oenococcus oeni (formerly Leuconostoc oenos) can perform malolactic fermentation, converting L-malate to L-lactate and carbon dioxide, in wines. The energy and redox potential required to support the growth of the micro-organism are supplied mainly by the consumption of carbohydrates via the heterolactic pathway. In the first steps of hexose metabolism two molecules of NAD(P)(+) are consumed, which must be regenerated in later reactions. The aim of this work was to test if aerobic growth of O. oeni promotes higher cell yields than anaerobic conditions, as has been shown for other lactic acid bacteria. O. oeni M42 was found to grow poorly under aerobic conditions with glucose as the only car…

Vascular oxidative stress, nitric oxide and atherosclerosis.

2014

In the vascular wall, reactive oxygen species (ROS) are produced by several enzyme systems including NADPH oxidase, xanthine oxidase, uncoupled endothelial nitric oxide synthase (eNOS) and the mitochondrial electron transport chain. On the other hand, the vasculature is protected by antioxidant enzyme systems, including superoxide dismutases, catalase, glutathione peroxidases and paraoxonases, which detoxify ROS. Cardiovascular risk factors such as hypercholesterolemia, hypertension, and diabetes mellitus enhance ROS generation, resulting in oxidative stress. This leads to oxidative modification of lipoproteins and phospholipids, mechanisms that contribute to atherogenesis. In addition, oxi…

Sildenafil protects epithelial cell through the inhibition of xanthine oxidase and the impairment of ROS production

2009

Recent reports suggest that xanthine oxidase (XO), a modified form of the native xanthine dehydrogenase enzyme, plays an important role in various forms of ischemic and vascular injuries, inflammatory diseases, and chronic heart failure. The XO inhibitors allopurinol and its oxidation product oxypurinol held considerable promises in the treatment of these conditions both in experimental animals and in human clinical trials. More recently, an endothelium-based protective effect of sildenafil, a well-known type-5 phosphodiesterase inhibitor, has been reported in preconditioning prior to ischemia/reperfusion in healthy human subjects. Based on the structural similarities between allopurinol an…

Mécanismes d'évolution de pseudomonas sp. adp sous pression de sélection exercée par l'atrazine

2010

L’atrazine est un pesticide qui est largement utilisé dans le monde depuis une quarantaine d’années. Son application répétée aaboutit non seulement à la contamination des eaux mais également à l’apparition de bactéries telluriques capables d’utiliserce xénobiotique comme source d’azote pour leur croissance. La caractérisation des gènes atz responsables de la dégradationde cette molécule a révélé qu’ils étaient largement dispersés et très conservés au sein du monde bactérien traduisant ainsid’une évolution et d’une dispersion récente de ces gènes, probablement concomitantes avec l’application d’atrazine dansl’environnement

Importance of genetic plasticity for microbial adaptation to pesticide biodegradation: in vitro evolution of Pseudomonas sp. ADP under atrazine or cy…

2011

International audience

The diversity of the population of Botrytis cinerea collected from french vineyards

2000

Genetic plasticity of atrazine-degrader: evidence for the deletion of atzABC genes in pseudomonas sp. adp in response to cyanuric acid selection pres…

2010

International audience; Several bacterial strains are known to metabolize s-triazines herbicides among which atrazine reported worldwidel to contaminate soil and water resources. The complete mineralization of atrazine to carbon dioxide and ammonium is catalyzed by 6 hydrolytic enzymes encoded by atzABCDEF genes located on the plasmid pADP1 in Pseudomonas ADP. The atzABC genes code for the upper pathway transforming atrazine to cyanuric acid, while the atzDEF genes code for the lower pathway transforming cyanuric acid to simple compounds. In order to study the genetic plasticity of the atrazine catabolic pathway, we performed an in vitro evolution study consisting in applying a continuous s…

Engineering a Saccharomyces cerevisiae Wine Yeast That Exhibits Reduced Ethanol Production during Fermentation under Controlled Microoxygenation Cond…

2006

ABSTRACTWe recently showed that expressing an H2O-NADH oxidase inSaccharomyces cerevisiaedrastically reduces the intracellular NADH concentration and substantially alters the distribution of metabolic fluxes in the cell. Although the engineered strain produces a reduced amount of ethanol, a high level of acetaldehyde accumulates early in the process (1 g/liter), impairing growth and fermentation performance. To overcome these undesirable effects, we carried out a comprehensive analysis of the impact of oxygen on the metabolic network of the same NADH oxidase-expressing strain. While reducing the oxygen transfer rate led to a gradual recovery of the growth and fermentation performance, its i…

La biopiraterie et le commerce des produits pharmaceutiques face aux droits des populations locales sur leurs savoirs traditionnels

2006

Collection des travaux du Credimi