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111.
de Souza Rocheli Meyer Jacqueline Schoenfeld Rodrigo da Costa Pedro Beschoren Passaglia Luciane M. P. 《Annals of microbiology》2015,65(2):951-964
Plant growth-promoting rhizobacteria (PGPR) are able to promote plant growth using a wide variety of mechanisms as well as provide bioprotection against biotic and abiotic stresses. The objectives of this study were to isolate and characterize putative PGPR associated with rice cultivars with a distinct tolerance to iron toxicity grown in two areas: one area with a well-established history of iron toxicity and another without iron toxicity. Bacterial strains were selectively isolated based on their growth in selective media and were identified by partial sequencing of their 16S rRNA genes. Bacterial isolates were evaluated for their ability to produce indolic compounds, siderophores, and ACC deaminase and to solubilize tricalcium phosphates. In vitro biological nitrogen fixation was evaluated for the bacterial isolates used in the inoculation experiments. A total of 329 bacterial strains were isolated. The composition of the bacterial genera and the occurrence of different plant growth-promoting (PGP) traits were significantly affected by the iron conditions and by the cultivar. Strains belonging to the Burkholderia and Enterobacter genera were the most abundant of all the Gram-negative isolates, and those belonging to the Paenibacillus and Bacillus genera were the most abundant of the Gram-positive isolates. A large number of putative PGPR belonging to different bacterial genera presented several PGP traits. Strains belonging to the Burkholderia, Chryseobacterium, and Ochrobactrum genera contributed to plant growth as well as to enhanced nutrient uptake of the rice plants in in vivo experiments. Growth and nutrient uptake of plants inoculated with isolate FeS53 (Paenibacillus sp.) in the presence of an iron excess were similar to those of plants submitted to the control iron condition, indicating that this bacterium can mitigate the effects caused by iron stress. 相似文献
112.
Cláudio de Oliveira Cunha Luiz Fernando Goda Zuleta Luiz Gonzaga Paula de Almeida Luciane Prioli Ciapina Wardsson Lustrino Borges Rosa Maria Pitard José Ivo Baldani Rosangela Straliotto Sérgio Miana de Faria Mariangela Hungria Benildo Sousa Cavada Fábio Martins Mercante Ana Tereza Ribeiro de Vasconcelos 《Journal of bacteriology》2012,194(23):6675-6676
The genus Burkholderia represents a challenge to the fields of taxonomy and phylogeny and, especially, to the understanding of the contrasting roles as either opportunistic pathogens or bacteria with biotechnological potential. Few genomes of nonpathogenic strains, especially of diazotrophic symbiotic bacteria, have been sequenced to improve understanding of the genus. Here, we contribute with the complete genome sequence of Burkholderia phenoliruptrix strain BR3459a (CLA1), an effective diazotrophic symbiont of the leguminous tree Mimosa flocculosa Burkart, which is endemic to South America. 相似文献
113.
Amato AA Rajagopalan S Lin JZ Carvalho BM Figueira AC Lu J Ayers SD Mottin M Silveira RL Souza PC Mourão RH Saad MJ Togashi M Simeoni LA Abdalla DS Skaf MS Polikparpov I Lima MC Galdino SL Brennan RG Baxter JD Pitta IR Webb P Phillips KJ Neves FA 《The Journal of biological chemistry》2012,287(33):28169-28179
The recent discovery that peroxisome proliferator-activated receptor γ (PPARγ) targeted anti-diabetic drugs function by inhibiting Cdk5-mediated phosphorylation of the receptor has provided a new viewpoint to evaluate and perhaps develop improved insulin-sensitizing agents. Herein we report the development of a novel thiazolidinedione that retains similar anti-diabetic efficacy as rosiglitazone in mice yet does not elicit weight gain or edema, common side effects associated with full PPARγ activation. Further characterization of this compound shows GQ-16 to be an effective inhibitor of Cdk5-mediated phosphorylation of PPARγ. The structure of GQ-16 bound to PPARγ demonstrates that the compound utilizes a binding mode distinct from other reported PPARγ ligands, although it does share some structural features with other partial agonists, such as MRL-24 and PA-082, that have similarly been reported to dissociate insulin sensitization from weight gain. Hydrogen/deuterium exchange studies reveal that GQ-16 strongly stabilizes the β-sheet region of the receptor, presumably explaining the compound's efficacy in inhibiting Cdk5-mediated phosphorylation of Ser-273. Molecular dynamics simulations suggest that the partial agonist activity of GQ-16 results from the compound's weak ability to stabilize helix 12 in its active conformation. Our results suggest that the emerging model, whereby "ideal" PPARγ-based therapeutics stabilize the β-sheet/Ser-273 region and inhibit Cdk5-mediated phosphorylation while minimally invoking adipogenesis and classical agonism, is indeed a valid framework to develop improved PPARγ modulators that retain antidiabetic actions while minimizing untoward effects. 相似文献
114.
This study was carried to investigate neutrophil function in the presence of Prototheca zopfii. For this purpose, bovine milk neutrophils were incubated in the absence (control) of and presence of P. zopfii, and then they were examined hydrogen peroxide (H2O2) production, antioxidant enzyme activities, and phagocytic capacity. Milk was collected from negative “California Mastitis
Test” (CMT) quarter from three lactating Holstein cows after induction of leukocytosis with an intramammary infusion of oyster
glycogen. H2O2 production was measured using the phenol red method. Catalase activity was measured following H2O2 reduction at 240 nm and the activity of glutathione reductase was determined by measuring the rate of NADPH oxidation at
340 nm. P. zopfii death was assessed by fluorescent microscopy using acridine orange assay and by colony forming units (CFUs). Comparisons
between the groups were initially performed by analysis of variance (ANOVA). Significant differences were then compared using
Tukey’s test with a significance coefficient of 0.05. Hydrogen peroxide production, catalase and glutathione reductase activities
by neutrophils incubated in presence of P. zopfii were stimulated five times, 21% and 27% respectively, compared to the unstimulated-neutrophils. Neutrophils did not affect
P. zopfii death as shown by microscopy and CFUs. These observations led to the conclusion that the P. zopfii promote a high increase of H2O2 production by neutrophils from bovine milk during algae exposition accompanied by increase of antioxidant enzyme activities;
however, this process did not affect P. zopfii death. 相似文献
115.
Sandro M. Hirabara Luciane C. Alberici Rafael H. Lambertucci Maria F. Cury Boaventura Anibal E. Vercesi 《BBA》2006,1757(1):57-66
Acute effects of free fatty acids (FFA) were investigated on: (1) glucose oxidation, and UCP-2 and -3 mRNA and protein levels in 1 h incubated rat soleus and extensor digitorium longus (EDL) muscles, (2) mitochondrial membrane potential in cultured skeletal muscle cells, (3) respiratory activity and transmembrane electrical potential in mitochondria isolated from rat skeletal muscle, and (4) oxygen consumption by anesthetized rats. Long-chain FFA increased both basal and insulin-stimulated glucose oxidation in incubated rat soleus and EDL muscles and reduced mitochondrial membrane potential in C2C12 myotubes and rat skeletal muscle cells. Caprylic, palmitic, oleic, and linoleic acid increased O2 consumption and decreased electrical membrane potential in isolated mitochondria from rat skeletal muscles. FFA did not alter UCP-2 and -3 mRNA and protein levels in rat soleus and EDL muscles. Palmitic acid increased oxygen consumption by anesthetized rats. These results suggest that long-chain FFA acutely lead to mitochondrial uncoupling in skeletal muscle. 相似文献
116.
Hirabara SM Silveira LR Alberici LC Leandro CV Lambertucci RH Polimeno GC Cury Boaventura MF Procopio J Vercesi AE Curi R 《Biochimica et biophysica acta》2006,1757(1):57-66
Acute effects of free fatty acids (FFA) were investigated on: (1) glucose oxidation, and UCP-2 and -3 mRNA and protein levels in 1 h incubated rat soleus and extensor digitorium longus (EDL) muscles, (2) mitochondrial membrane potential in cultured skeletal muscle cells, (3) respiratory activity and transmembrane electrical potential in mitochondria isolated from rat skeletal muscle, and (4) oxygen consumption by anesthetized rats. Long-chain FFA increased both basal and insulin-stimulated glucose oxidation in incubated rat soleus and EDL muscles and reduced mitochondrial membrane potential in C2C12 myotubes and rat skeletal muscle cells. Caprylic, palmitic, oleic, and linoleic acid increased O(2) consumption and decreased electrical membrane potential in isolated mitochondria from rat skeletal muscles. FFA did not alter UCP-2 and -3 mRNA and protein levels in rat soleus and EDL muscles. Palmitic acid increased oxygen consumption by anesthetized rats. These results suggest that long-chain FFA acutely lead to mitochondrial uncoupling in skeletal muscle. 相似文献
117.
Chondroitin sulfate, a glycosaminoglycan that is widely distributed among mammals, is used as a therapeutic agent in various diseases. Here, we focus on its absorption, excretion and tissue accumulation in rats. The concentration of 35S-chondroitin sulfate (35S-CS) in plasma reaches a peak in the first 5 min after intravenous administration and simultaneously increases in the urine. Approximately 25% of the 35S found in the urine appears as inorganic sulfate, indicating that 35S-CS is partially degraded during its renal filtration. The glycosaminoglycan is retained mainly by the liver and the kidney, where the amount of 35S reaches a plateau in the first 30 min, remains constant up to 2 h and then decreases markedly. Renal filtration and organ accumulation of 35S-CS decreases as the size of the glycosaminoglycan is reduced, especially in the liver. A derivative of 35S-CS that resists hyaluronidase digestion due to reduction of its glucuronic acid carboxyl groups appears at lower concentrations in plasma and in urine when compared with native 35S-CS. This derivative reaches higher levels in the kidney but lower levels in the liver when compared with the native molecule. Overall, our results indicate a balance between renal and hepatic mechanisms for removing chondroitin sulfate from plasma. The renal filtration increases as the molecular weight of the glycosaminoglycan decreases, whereas hepatic removal requires structural integrity and the presence of high-molecular-weight chains. 相似文献
118.
Jamile F. Gonçalves Fernando T. Nicoloso Alexssandro G. Becker Luciane B. Pereira Luciane A. Tabaldi Denise Cargnelutti Carla M. G. de Pelegrin Valderi L. Dressler João B. T. da Rocha Maria Rosa C. Schetinger 《Biologia》2009,64(2):310-318
In this study, the effects of cadmium chloride (CdCl2) on plant growth, histology of roots, photosynthetic pigments content, δ-aminolevulinic acid dehydratase (ALA-D; E.C. 4.2.1.24) and acid phosphatase activities (AP; E.C. 3.1.3.2), soluble phosphorus
(Pi) measurement and mineral nutrients content in cucumber seedlings (Cucumis sativus L.) were investigated. Cucumber seedlings were grown in vitro in an agar-solidified substrate containing four CdCl2 treatments (0, 100, 400, and 1000 μM) for ten days. Cd was readily absorbed by seedlings and its content was greater in the
roots than in the shoot. Cd reduced shoot and root length, and fresh and dry biomass of seedlings. Inhibition of root cell
elongation in Cd-treated seedlings was observed by the increase of the mean radial size of cells belonging to three zones
of the root tip. The highest level of Cd reduced in a similar manner chlorophyll a, chlorophyll b and total chlorophyll contents.
Increasing concentrations of Cd resulted in a linear decrease in carotenoids levels of cotyledons. Interestingly, the ALA-D
activity in cotyledons was inhibited only at the highest level of Cd. Root and shoot AP activities were, respectively, activated
and inhibited at all CdCl2 concentrations. Root Pi concentration was increased in all Cd treatments and it was not altered in the shoot tissues. Moreover,
in general, the nutrient contents were increased in the root and decreased in the shoot. Therefore, we suggest that Cd affects
negatively growth, photosynthetic pigments, ALA-D and AP activities and partition of mineral nutrients in cucumber seedlings. 相似文献
119.
Spatial Evaluation and Modeling of Dengue Seroprevalence and Vector Density in Rio de Janeiro,Brazil
Nildimar Alves Honório Rita Maria Ribeiro Nogueira Cláudia Torres Code?o Marilia Sá Carvalho Oswaldo Gon?alves Cruz M?nica de Avelar Figueiredo Mafra Magalh?es Josélio Maria Galv?o de Araújo Eliane Saraiva Machado de Araújo Marcelo Quintela Gomes Luciane Silva Pinheiro Célio da Silva Pinel Ricardo Louren?o-de-Oliveira 《PLoS neglected tropical diseases》2009,3(11)