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991.
Claire-Emmanuelle Marcato Rabi Mohtar Jean-Claude Revel Philippe Pouech Mohamed Hafidi Maritxu Guiresse 《International biodeterioration & biodegradation》2009,63(3):260-266
Changes in pig slurry organic matter (OM) during anaerobic digestion (AD) were studied in a reactor to characterize OM evolution through AD. OM maturity and stability were evaluated using different biological and physico-chemical methods. Germination and growth chamber experiments revealed a higher maturity of digested slurry (DS) than raw slurry (RS). Soil incubations showed that DS was more stable than RS with a C-mineralization of 12.0 g CO2-C 100 g?1 Corg after 49 days as compared to 17.6 g CO2-C 100 g?1 Corg. Biochemical fractionation showed a relative increase in stable compounds such as hemicellulose-like and lignin-like molecules. Fourier-transform infrared spectroscopy showed some changes in the chemical structures of OM with a reduction in the aliphatic chain, lipid and polysaccharide levels. A comparison between the evolution of OM during AD and the first weeks of a composting process showed almost identical changes. Finally a theoretical method called Fictitious Atomic-group Separation was applied to the elemental compositions of RS and DS. DS was less humified than RS and presented the properties of a fulvic acid, indicating that the observed stability in DS was mainly due to the biodegradation of the most labile compounds. 相似文献
992.
Overexpression of a grapevine R2R3-MYB factor in tomato affects vegetative development,flower morphology and flavonoid and terpenoid metabolism 总被引:1,自引:0,他引:1
993.
Two new species of the genus Corollospora, namely, C. anglusa sp. nov. with its anamorph Varicosporina anglusa sp. nov. and C. portsaidica sp. nov., which were isolated from the coast of the Mediterranean Sea in Egypt, are described in this article based on morphological
and molecular evidence. The two new species have one-septate ascospores. Corollospora anglusa resembles C. gracilis by having narrow one-septate hyaline ascospores; however, they differ in ascomata and ascospore dimensions and in pure culture
characteristics. Single-ascospore culture of C. anglusa produces the conidia of its anamorph, whereas an anamorph has not been reported for C. gracilis. Varicosporina anglusa differs from the other two known Varicosporina species by having conidial branches that are filamentous, rectangularly branched, hypha like, and disarticulated into two-
or one-celled fragments. Corollospora portsaidica is morphologically similar to C. cinnamomea, but the two species differ in the dimensions, shape, and ornamentation of the ascospores. The new Corollospora species were confirmed to be divergent from other similar Corollospora species based on phylogenetic analyses of partial sequences of the LSU rDNA region. 相似文献
994.
The genetic characterization of natural populations of common pandora (Pagellus erythrinus, Sparidae) was studied using allozyme markers. Fish samples (n = 360) were collected from five locations along the Tunisian coasts and one from the Libyan coast. From eight enzymatic systems,
12 putative enzyme-coding loci were resolved, 8 of which were polymorphic at a level of 99%. F statistics indices revealed a significant departure from panmixia with heterozygote deficiencies and a slight genetic differentiation
between samples. Neighbor-joining dendrogram constructed by Reynolds genetic distance showed that the populations sampled
from the southeastern Mediterranean Sea were more differentiated from the others. 相似文献
995.
Eddy Karnabi Yongxia Qu Salvatore Mancarella Raj Wadgaonkar Mohamed Boutjdir 《Biochemical and biophysical research communications》2009,384(4):409-414
Cav1.2 (α1C) and Cav1.3 (α1D) L-type Ca channels are co-expressed in the heart. To date, there are no pharmacological or biophysical tools to separate α1D from α1C Ca currents (ICa-L) in cardiomyocytes. Here, we established a physiological model to study α1D ICa-L in native myocytes using RNA interference. Transfection of rat neonatal cardiomyocytes (RNC) with α1C specific siRNA resulted in low silencing efficiency (50-60%) at the mRNA and protein levels. The use of lentivirus shRNA resulted in 100% transfection efficiency and 92% silencing of the α1C gene by real-time PCR and Western blot. Electrophysiological experiments showed that the total ICa-L was similarly reduced by 80% in lentivirus transfected cells. Both biochemical and functional data demonstrated high transfection and silencing efficiency in the cardiomyocytes using lentiviral shRNA. This novel approach allows for the assessments of the roles of α1C and α1D Ca channels in native myocytes and could be used to examine their roles in physiological and pathological settings. 相似文献
996.
Mohamed Ali Borgi Moez Rhimi Nushin Aghajari Mamdouh Ben Ali Michel Juy Richard Haser Samir Bejar 《Biologia》2009,64(5):845-851
The implication of the original alanine 63 (Ala63) and the unique cysteine 306 (Cys306) residues in the thermostability of
the Streptomyces sp. SK glucose isomerase (SKGI) were investigated by site-directed mutagenesis and homology modelling. The Cys306 to Ala
mutation within SKGI dramatically affected its thermal stability by decreasing the half-life from 80 to 15 min at 90°C while
the Ala63 to Ser replacement shifted this half-life to 65 min. The electrophoretic analysis proves that the residue Cys306
participates in oligomerization of the SKGI. Its stabilizing role is materialized by hydrogen bonds established with arginines
at positions 284 and 259, as deduced from the constructed three-dimensional model. We have also shown that the presence of
an Ala63 instead of Ser63 seems to be more suitable for enzyme thermostability by maintaining hydrophobic pocket that contributes
to the protection of the enzyme active site. 相似文献
997.
998.
Food partitioning and spatial subsidy in shelter‐limited fishes inhabiting patchy reefs of Patagonia
D. E. Galvn F. Botto A. M. Parma L. Bandieri N. Mohamed O. O. Iribarne 《Journal of fish biology》2009,75(10):2585-2605
The diets of the most conspicuous reef‐fish species from northern Patagonia, the carnivorous species Pseudopercis semifasciata, Acanthistius patachonicus, Pinguipes brasilianus and Sebastes oculatus were studied. Pinguipes brasilianus had the narrowest diet and most specialized feeding strategy, preying mostly on reef‐dwelling organisms such as sea urchins, limpets, bivalves, crabs and polychaetes. The diet of A. patachonicus was characterized by the presence of reef and soft‐bottom benthic organisms, mainly polychaetes, crabs and fishes. Pseudopercis semifasciata showed the broadest spectrum of prey items, preying upon reef, soft‐bottom and transient organism (mainly fishes, cephalopods and crabs). All S. oculatus guts were empty, but stable‐isotope analyses suggested that this species consumed small fishes and crabs. In general, P. brasilianus depended on local prey populations and ate different reef‐dwelling prey than the other species. Pseudopercis semifasciata, A. patachonicus and probably S. oculatus, however, had overlapping trophic niches and consumed resources from adjacent environments. The latter probably reduces the importance of food as a limiting resource for these reef‐fish populations, facilitating their coexistence in spite of their high trophic overlap. 相似文献
999.
1000.
Tumor necrosis factor (TNF) and members of the interferon (IFN) family have been shown to independently inhibit the replication of a variety of viruses. In addition, previous reports have shown that treatment with various combinations of these antiviral cytokines induces a synergistic antiviral state that can be significantly more potent than addition of any of these cytokines alone. The mechanism of this cytokine synergy and its effects on global gene expression, however, are not well characterized. Here, we use DNA microarray analysis to demonstrate that treatment of uninfected primary human fibroblasts with TNF plus IFN-β induces a distinct synergistic state characterized by significant perturbations of several hundred genes which are coinduced by the individual cytokines alone, as well as the induction of more than 850 novel host cell genes. This synergy is mediated directly by the two ligands, not by intermediate secreted factors, and is necessary and sufficient to completely block the productive replication and spread of myxoma virus in human fibroblasts. In contrast, the replication of two other poxviruses, vaccinia virus and tanapox virus, are only partially inhibited in these cells by the synergistic antiviral state, whereas the spread of both of these viruses to neighboring cells was efficiently blocked. Taken together, our data indicate that the combination of TNF and IFN-β induces a novel synergistic antiviral state that is highly distinct from that induced by either cytokine alone. 相似文献