Lien non specifie dans les modeles lineaires generalises.

regression analysis ; evaluation ; econometrie

Comparaison ARM écho-doppler pour l'étude des sténoses carotidiennes extracraniennes

TOURS-BU Médecine (372612103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Pseudomonas putida KT2440 response to nickel or cobalt induced stress by quantitative proteomics

cited By 14International audienceNickel and cobalt are obligate nutrients for the gammaproteobacteria but when present at high concentrations they display toxic effects. These two metals are present in the environment, their origin being either from natural sources or from industrial use. In this study, the effect of inhibitory concentrations of Ni or Co was assessed on the soil bacterium Pseudomonas putida KT2440 using a proteomic approach. The identification of more than 400 spots resulted in the quantification of 160 proteins that underwent significant variations in cells exposed to Co and Ni. This analysis allowed us to depict the cellular response of P. putida cells toward metallic stress. More precisely, the parallel comparison of the two proteomes showed distinct responses of P. putida to Ni or Co toxicity. The most striking effect of Co was revealed by the accumulation of several proteins involved in the defense against oxidative damage, which include proteins involved in the detoxification of the reactive oxygen species, superoxides and peroxides. The up-regulation of the genes encoding these enzymes was confirmed using qRT-PCR. Interestingly, in the Ni-treated samples, sodB, encoding superoxide dismutase, was up-regulated, indicating the apparition of superoxide radicals due to the presence of Ni. However, the most striking effect of Ni was the accumulation of several proteins involved in the synthesis of amino acids. The measurement of the amount of amino acids in Ni-treated cells revealed a strong accumulation of glutamate. © 2013 The Royal Society of Chemistry

Mass transportation and the consistency of the empirical optimal conditional locations

International audienc

Catalytic properties of a highly thermoactive polygalacturonase from the mesophilic fungus Penicillium occitanis and use in juice clarification

A new polygalacturonase (PG1) is purified to homogeneity from the hyper-pectinolytic mutant (CT1) of Penicillium occitanis by using two chromatographic steps. The purified PGI exhibited a very high specific activity toward PGA, namely 57533.2 U/mg of protein and a high optimal temperature, 70 degrees C. In our knowledge, it is one of the highest temperature optima described till now, even among those reported for thermophilic fungi; recalling here that our fungus is a mesophilic one. The N-terminal sequence was almost identical to that deduced from the previously cloned pga1 gene. The mass spectrometry analysis of PG1 further confirmed its belonging to the pga1 gene. As the peptide sequence of the pga1 bears the signature of endopolygalacturonases, we brought in this work evidences that it belongs to enzymes that hydrolyze pectin by endo-fashion. Indeed, during the hydrolysis of polygalacturonic acid by PG1, the viscosity drops very quickly while reducing sugars were released very slowly. In addition, thin layer chromatography showed that mainly oligosaccharides were released from PGA, namely tetra and trigalacturonic acids. The purified PGI was able to enhance the clarification of citrus juice. Considering all these properties, this novel fungal would be an interesting biocatalyst for future application in fruit and vegetable transformation. (C) 2016 Elsevier B.V. All rights reserved