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Molina-Heredia FP Díaz-Quintana A Hervás M Navarro JA De La Rosa MA 《The Journal of biological chemistry》1999,274(47):33565-33570
A number of surface residues of cytochrome c(6) from the cyanobacterium Anabaena sp. PCC 7119 have been modified by site-directed mutagenesis. Changes were made in six amino acids, two near the heme group (Val-25 and Lys-29) and four in the positively charged patch (Lys-62, Arg-64, Lys-66, and Asp-72). The reactivity of mutants toward the membrane-anchored complex photosystem I was analyzed by laser flash absorption spectroscopy. The experimental results indicate that cytochrome c(6) possesses two areas involved in the redox interaction with photosystem I: 1) a positively charged patch that may drive its electrostatic attractive movement toward photosystem I to form a transient complex and 2) a hydrophobic region at the edge of the heme pocket that may provide the contact surface for the transfer of electrons to P(700). The isofunctionality of these two areas with those found in plastocyanin (which acts as an alternative electron carrier playing the same role as cytochrome c(6)) are evident. 相似文献
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Rosa Anna Iorio Stefano Del Duca Elisabetta Calamelli Chiara Pula Magda Lodolini Fortuna Scamardella Andrea Pession Giampaolo Ricci 《PloS one》2013,8(1)
Allergy to citrus fruits is often associated with pollinosis and sensitization to other plants due to a phenomenon of cross-reactivity. The aims of the present study were to highlight the cross-reactivity among citrus and the major allergenic pollens/fruits, throughout clinical and molecular investigations, and to evaluate the sensitization frequency to citrus fruits in a population of children and adults with pollinosis. We found a relevant percentage of sensitisation (39%) to citrus fruits in the patients recruited and in all of them the IgE-mediated mechanism has been confirmed by the positive response to the prick-to-prick test. RT-PCR experiments showed the expression of Cit s 1, Cit s 3 and a profilin isoform, already described in apple, also in Citrus clementine pollen. Data of multiple sequence alignments demonstrated that Citrus allergens shared high percentage identity values with other clinically relevant species (i.e. Triticum aestivum, Malus domestica), confirming the possible cross-allergenicity citrus/grasses and citrus/apple. Finally, a novelty of the present work has been the expression of two phospholipaseA2 isoforms (PLA2 α and β) in Citrus as well as in Triticum pollens; being PLA2 able to generate pro-inflammatory factors, this enzyme could participate in the activation of the allergenic inflammatory cascade. 相似文献
206.
Eva Villamón Ana P. Berbegall Marta Piqueras Irene Tadeo Victoria Castel Anna Djos Tommy Martinsson Samuel Navarro Rosa Noguera 《PloS one》2013,8(1)
Background/Aim
Genetic analysis in neuroblastoma has identified the profound influence of MYCN amplification and 11q deletion in patients’ prognosis. These two features of high-risk neuroblastoma usually occur as mutually exclusive genetic markers, although in rare cases both are present in the same tumor. The purpose of this study was to characterize the genetic profile of these uncommon neuroblastomas harboring both these high-risk features.Methods
We selected 18 neuroblastomas with MNA plus 11q loss detected by FISH. Chromosomal aberrations were analyzed using Multiplex Ligation-dependent Probe Amplification and Single Nucleotide Polymorphism array techniques.Results and Conclusion
This group of tumors has approximately the same high frequency of aberrations as found earlier for 11q deleted tumors. In some cases, DNA instability generates genetic heterogeneity, and must be taken into account in routine genetic diagnosis. 相似文献207.
Rosa Tundis Federica Menichini Filomena Conforti Monica R. Loizzo Marco Bonesi Giancarlo Statti 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):818-824
From the aerial parts of Salsola oppositofolia, S. soda and S. tragus an alkaloid extract was obtained and tested to evaluate antioxidant and anti-cholinesterase activities. The in vitro study of the antioxidant activity by the DPPH method revealed a significant activity of Salsola alkaloid extracts with IC50 values ranging from 16.30 μg/mL for S. oppositifolia to 26.17 μg/mL for S. tragus. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were evaluated. S. tragus alkaloid extract exerted the highest inhibitory activity against AChE (IC50 of 30.2 μg/mL) and BChE (IC50 of 26.5 μg/mL). Interestingly, S. soda and S. oppositifolia exhibited a selective inhibitory activity against BChE with IC50 values of 34.3 μg/mL and 32.7 μg/mL, respectively. Tetrahydroisoquinoline alkaloids were identified and quantified by GC/MS analysis. 相似文献
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Javier Palazn Rosa M. Cusid Mercedes Bonfill Anna Mallol Elisabet Moyano Carmen Morales M. Teresa Piol 《Plant Physiology and Biochemistry》2003,41(11-12):1019-1025
We tested the effect of the presence in the culture medium of chitosan, vanadyl sulfate or methyl jasmonate on growth and ginsenoside production of three stable hairy root lines of Panax ginseng C.A. Meyer showing different morphological phenotypes C-M, HR-M and T-M. The response depended upon line phenotype, specificity of the elicitor and the stage of growth at which the lines were treated. The highest ginsenoside yield was found when methyl jasmonate was added during the progressive deceleration growth phase (on day 25 of culture). In this case, the ginsenoside content reached at the end of the culture (day 28) by root lines C-M, HR-M and T-M was, respectively, 2, 1.8 and 4 times higher than the highest content achieved, also at the end of the culture, by the corresponding untreated root lines. Under the same conditions, the ginsenoside content in the presence of vanadyl sulfate also increased considerably, while with chitosan it clearly decreased. The ginsenoside pattern in response to the presence of the elicitors is also considered. 相似文献
210.
Coumarin inhibits the growth of carrot (Daucus carota L. cv. Saint Valery) cells in suspension culture 总被引:1,自引:0,他引:1
We used a carrot (Daucus carota L. cv. Saint Valery) cell suspension culture as a simplified model system to study the effects of the allelochemical compound coumarin (1,2 benzopyrone) on cell growth and utilisation of exogenous nitrate, ammonium and carbohydrates. Exposure to micromolar levels of coumarin caused severe inhibition of cell growth starting from the second day of culture onwards. At the same time, the presence of 50 mumol/L coumarin caused accumulation of free amino acids and of ammonium in the cultured cells, and stimulated their glutamine synthetase, glutamate dehydrogenase, glucose-6-phosphate dehydrogenase and phosphoenolpyruvate carboxylase activities. Malate dehydrogenase, on the other hand, was inhibited under the same conditions. These effects were interpreted in terms of the stimulation of protein catabolism and/or interference with protein biosynthesis induced by coumarin. This could have led to a series of compensatory changes in the activities of enzymes linking nitrogen and carbon metabolism. Because coumarin seemed to abolish the exponential phase and to accelerate the onset of the stationary phase of cell growth, we hypothesise that such allelochemical compounds may act in nature as an inhibitor of the cell cycle and/or as a senescence-promoting substance. 相似文献