Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Potentiels et leviers pour développer la production et l’utilisation des protéagineux dans le cadre d’une agriculture durable en Bourgogne

A multi-partners strategy is engaged at level of Burgundy-France territory, to evaluate potentials and identify levers for the development of a chain from production to uses of grain legumes. The analysis of genotype x environment interaction and climatic factors is supported by a second year of field trials of grain legumes varieties (pea and faba bean of spring or winter sowing types. The statistical analysis of climatic data over the 1961-2009 period, has allowed to build Burgundy maps of freezing risk and late spring heat stress risk and we are able to suggest pea or faba bean genotypes, better adapted to the region. The sustainability of cropping systems involving or not grain legumes was evaluated according several criteria (agronomy, energy and other input, work organisation). It has confirmed the positive effect of inserting grain legumes, on the reduction (i) of N fertiliser, energy and pesticide uses, (ii) for easier weed control (iii) on the economic bilan assessed over whole cropping system. On 2 sites, « in situ » most measurement of N2Oemissions by soils containing grain legume crop residues were higher than those containing cereal residues. Offering to farmers varieties with good level of stress resistance and good productivity will be a key point for the development of grain legume crops. The economic analysis has identified the potential value of developing contracts between produces and collectors which will secure prices and market. The technical development of a high quality “chain” and its promotion may be valuable provided efforts on traceabilty and on labelling.Une démarche multi-partenaires est engagée sur le territoire de la région Bourgogne, pour évaluer les potentiels et identifier des leviers au développement d’une filière protéagineuse. L’analyse des interactions génotype x environnement et des facteurs climatiques est appuyée par une deuxième année d’expérimentation variétale de protéagineux (pois et féveroles d’hiver et de printemps). Une étude fréquentielle sur la période 1961-2009 a permis de cartographier les risques de gel hivernal et de fortes chaleurs en fin de cycle cultural en Bourgogne et nous pouvons proposer des variétés de pois et de féveroles mieux adaptées à la région. Le volet d’évaluation multicritères de la durabilité des systèmes de culture bourguignons, comparant des systèmes avec et sans protéagineux, a permis de confirmer et de quantifier l’intérêt de l’insertion de protéagineux, qui passe notamment par une diminution de l’IFT moyen et des doses d’azote, une augmentation de la robustesse économique (économie d’engrais azotés et énergie fossile sur l’ensemble de la rotation), la diversification des rotations en offrant de nouvelles possibilités de gestion des adventices. Sur 2 sites, le volet « environnemental » a montré en conditions « in situ », que les émissions de N2O par les sols contenant des résidus de pois ne sont en général pas supérieures à celles des sols contenant des résidus de céréales. La proposition de variétés tolérantes aux principaux stress en culture et de bonne productivité sera une clef essentielle du développement des cultures protéagineuses. L’analyse économique a identifié un intérêt du développement de la contractualisation dans la filière et de la mise en place et de la promotion d’une filière de qualité, en accentuant les exigences en matière de traçabilité et d’étiquetage

Sex and parasites: genomic and transcriptomic analysis of Microbotryum lychnidis-dioicae, the biotrophic and plant-castrating anther smut fungus

Background: The genus Microbotryum includes plant pathogenic fungi afflicting a wide variety of hosts with anther smut disease. Microbotryum lychnidis-dioicae infects Silene latifolia and replaces host pollen with fungal spores, exhibiting biotrophy and necrosis associated with altering plant development. Results: We determined the haploid genome sequence for M. lychnidis-dioicae and analyzed whole transcriptome data from plant infections and other stages of the fungal lifecycle, revealing the inventory and expression level of genes that facilitate pathogenic growth. Compared to related fungi, an expanded number of major facilitator superfamily transporters and secretory lipases were detected; lipase gene expression was found to be altered by exposure to lipid compounds, which signaled a switch to dikaryotic, pathogenic growth. In addition, while enzymes to digest cellulose, xylan, xyloglucan, and highly substituted forms of pectin were absent, along with depletion of peroxidases and superoxide dismutases that protect the fungus from oxidative stress, the repertoire of glycosyltransferases and of enzymes that could manipulate host development has expanded. A total of 14 % of the genome was categorized as repetitive sequences. Transposable elements have accumulated in mating-type chromosomal regions and were also associated across the genome with gene clusters of small secreted proteins, which may mediate host interactions. Conclusions: The unique absence of enzyme classes for plant cell wall degradation and maintenance of enzymes that break down components of pollen tubes and flowers provides a striking example of biotrophic host adaptation

Combined Bacterial Meningitis and Infective Endocarditis: When Should We Search for the Other When Either One is Diagnosed?

Auteurs groupes collaboratifs AEPEI study group & the COMBAT study groupInternational audienc